1.
Sustainable energy
–
Sustainable energy is energy that is consumed at insignificant rates compared to its supply and with manageable collateral effects, especially environmental effects. Another common definition of energy is an energy system that serves the needs of the present without compromising the ability of future generations to meet their needs. The organizing principle for sustainability is sustainable development, which includes the four interconnected domains, ecology, economics, politics, sustainability science is the study of sustainable development and environmental science. Costs have fallen dramatically in recent years, and continue to fall, most of these technologies are either economically competitive or close to being so. Increasingly, effective government policies support investor confidence and these markets are expanding, considerable progress is being made in the energy transition from fossil fuels to ecologically sustainable systems, to the point where many studies support 100% renewable energy. Energy efficiency and renewable energy are said to be the pillars of sustainable energy. In the broader context of development, there are three pillars, ecology, economy and society. Sustainable Energy has two key components, renewable energy and energy efficiency. And, The solution will lie in finding sustainable energy sources, – Sustainable Energy by J. W. Tester, et al. from MIT Press. – Invest, a green technology non-profit organization, Energy which is replenishable within a human lifetime and causes no long-term damage to the environment. Sustainable energy can produce some pollution of the environment, as long as it is not sufficient to prohibit use of the source for an indefinite amount of time. Sustainable energy is also distinct from low-carbon energy, which is only in the sense that it does not add to the CO2 in the atmosphere. Green Energy is energy that can be extracted, generated, and/or consumed without any significant negative impact to the environment, the planet has a natural capability to recover which means pollution that does not go beyond that capability can still be termed green. Green power is a subset of renewable energy and represents those renewable energy resources and technologies that provide the highest environmental benefit. The U. S. Environmental Protection Agency defines green power as electricity produced from solar, wind, geothermal, biogas, biomass, customers often buy green power for avoided environmental impacts and its greenhouse gas reduction benefits. The International Energy Agency states that, Conceptually, one can define three generations of technologies, reaching back more than 100 years. First-generation technologies emerged from the revolution at the end of the 19th century and include hydropower, biomass combustion and geothermal power. Some of these technologies are still in widespread use, second-generation technologies include solar heating and cooling, wind power, modern forms of bioenergy and solar photovoltaics. These are now entering markets as a result of research, development, many of the technologies reflect significant advancements in materials
2.
Energy conservation
–
Energy conservation refers to the reducing of energy consumption through using less of an energy service. Energy conservation differs from efficient energy use, which refers to using less energy for a constant service, driving less is an example of energy conservation. Driving the same amount with a higher mileage vehicle is an example of energy efficiency, Energy conservation and efficiency are both energy reduction techniques. Energy conservation is a part of the concept of sufficiency, even though energy conservation reduces energy services, it can result in increased environmental quality, national security, personal financial security and higher savings. It is at the top of the energy hierarchy. It also lowers energy costs by preventing future resource depletion, some countries employ energy or carbon taxes to motivate energy users to reduce their consumption. Carbon taxes can allow consumption to shift to power and other alternatives that carry a different set of environmental side effects. Meanwhile, taxes on all energy consumption stand to reduce energy use across the board, the State of California employs a tiered energy tax whereby every consumer receives a baseline energy allowance that carries a low tax. As usage increases above that baseline, the tax is increasing drastically, such programs aim to protect poorer households while creating a larger tax burden for high energy consumers. One of the ways to improve energy conservation in buildings is to use an energy audit. This is normally accomplished by trained professionals and can be part of some of the programs discussed above. In addition, recent development of smartphone apps enable homeowners to complete relatively sophisticated energy audits themselves, building technologies and smart meters can allow energy users, business and residential, to see graphically the impact their energy use can have in their workplace or homes. Advanced real-time energy metering is able to help save energy by their actions. In passive solar building design, windows, walls, and floors are made to collect, store and this is called passive solar design or climatic design because, unlike active solar heating systems, it doesnt involve the use of mechanical and electrical devices. The key to designing a passive building is to best take advantage of the local climate. Elements to be considered include window placement and glazing type, thermal insulation, thermal mass, passive solar design techniques can be applied most easily to new buildings, but existing buildings can be retrofitted. In the United States, suburban infrastructure evolved during an age of easy access to fossil fuels. Zoning reforms that allow greater urban density as well as designs for walking and bicycling can greatly reduce energy consumed for transportation, consumers are often poorly informed of the savings of energy efficient products
3.
Efficient energy use
–
Efficient energy use, sometimes simply called energy efficiency, is the goal to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve, installing fluorescent lights, LED lights or natural skylights reduces the amount of energy required to attain the same level of illumination compared with using traditional incandescent light bulbs. Improvements in energy efficiency are generally achieved by adopting an efficient technology or production process or by application of commonly accepted methods to reduce energy losses. There are many motivations to improve energy efficiency, reducing energy use reduces energy costs and may result in a financial cost saving to consumers if the energy savings offset any additional costs of implementing an energy efficient technology. Reducing energy use is seen as a solution to the problem of reducing greenhouse gas emissions. Energy efficiency and renewable energy are said to be the pillars of sustainable energy policy and are high priorities in the sustainable energy hierarchy. Energy efficiency has proved to be a strategy for building economies without necessarily increasing energy consumption. For example, the state of California began implementing energy-efficiency measures in the mid-1970s, including building code, during the following years, Californias energy consumption has remained approximately flat on a per capita basis while national US consumption doubled. In general, up to 75% of the electricity used in the US today could be saved with efficiency measures that cost less than the electricity itself. The same holds true for this is home and there is 78% of electricity uses D in your home-owners, in fact, researchers at the US Department of Energy and their consortium, Residential Energy Efficient Distribution Systems have found that duct efficiency may be as low as 50–70%. The US Department of Energy has stated there is potential for energy saving in the magnitude of 90 Billion kWh by increasing home energy efficiency. Other studies have emphasized this.2 percent average growth anticipated through 2020 in a business-as-usual scenario, international standards ISO17743 and ISO17742 provide a documented methodology for calculating and reporting on energy savings and energy efficiency for countries and cities. Modern appliances, such as, freezers, ovens, stoves, dishwashers, installing a clothesline will significantly reduce ones energy consumption as their dryer will be used less. Current energy efficient refrigerators, for example, use 40 percent less energy than conventional models did in 2001, in the US, the corresponding figures would be 17 billion kWh of electricity and 27,000,000,000 lb CO2. According to a 2009 study from McKinsey & Company the replacement of old appliances is one of the most efficient global measures to reduce emissions of greenhouse gases. Modern power management systems also reduce energy usage by idle appliances by turning them off or putting them into a low-energy mode after a certain time, many countries identify energy-efficient appliances using energy input labeling. The impact of energy efficiency on peak demand depends on when the appliance is used, for example, an air conditioner uses more energy during the afternoon when it is hot. Therefore, an efficient air conditioner will have a larger impact on peak demand than off-peak demand
4.
Green building
–
In other words, green building design involves finding the balance between homebuilding and the sustainable environment. This requires close cooperation of the team, the architects, the engineers. The Green Building practice expands and complements the classical building design concerns of economy, utility, durability, other certificates system that confirms the sustainability of buildings is the British BREEAM for buildings and large scale developments. Other related topics include sustainable design and green architecture, Sustainability may be defined as meeting the needs of present generations without compromising the ability of future generations to meet their needs. Although some green building programs dont address the issue of the existing homes, others do. Green construction principles can easily be applied to work as well as new construction. A2009 report by the U. S, general Services Administration found 12 sustainably-designed buildings that cost less to operate and have excellent energy performance. In addition, occupants were overall more satisfied with the building than those in commercial buildings. These are eco-friendly buildings. Globally buildings are responsible for a share of energy, electricity, water. The building sector has the greatest potential to deliver significant cuts in emissions at little or no cost, buildings account for 18% of global emissions today, or the equivalent of 9 billion tonnes of CO2 annually. Since construction almost always degrades a building site, not building at all is preferable to green building, the second rule is that every building should be as small as possible. The third rule is not to contribute to sprawl, even if the most energy-efficient, environmentally sound methods are used in design, buildings account for a large amount of land. According to the National Resources Inventory, approximately 107 million acres of land in the United States are developed, the concept of sustainable development can be traced to the energy crisis and environmental pollution concerns of the 1960s and 1970s. The Rachel Carson book, “Silent Spring”, published in 1962, is considered to be one of the first initial efforts to describe sustainable development as related to green building. The green building movement in the U. S. originated from the need and desire for energy efficient. There are a number of motives for building green, including environmental, economic, however, modern sustainability initiatives call for an integrated and synergistic design to both new construction and in the retrofitting of existing structures. Also known as design, this approach integrates the building life-cycle with each green practice employed with a design-purpose to create a synergy among the practices used. Green building brings together a vast array of practices, techniques, the essence of green building is an optimization of one or more of these principles
5.
Geothermal heat pump
–
A geothermal heat pump or ground source heat pump is a central heating and/or cooling system that transfers heat to or from the ground. It uses the earth as a source or a heat sink. They are also known by names, including geoexchange, earth-coupled. Ground source heat pumps harvest heat absorbed at the Earths surface from solar energy, the temperature in the ground below 6 metres is roughly equal to the mean annual air temperature at that latitude at the surface. Like a refrigerator or air conditioner, these use a heat pump to force the transfer of heat from the ground. Heat pumps can transfer heat from a space to a warm space, against the natural direction of flow. The core of the pump is a loop of refrigerant pumped through a vapor-compression refrigeration cycle that moves heat. A ground source heat pump exchanges heat with the ground and this is much more energy-efficient because underground temperatures are more stable than air temperatures through the year. Seasonal variations drop off with depth and disappear below 7 metres to 12 metres due to thermal inertia, like a cave, the shallow ground temperature is warmer than the air above during the winter and cooler than the air in the summer. A ground source heat pump extracts ground heat in the winter, some systems are designed to operate in one mode only, heating or cooling, depending on climate. Geothermal pump systems reach fairly high coefficient of performance,3 to 6, on the coldest of winter nights, Ground source heat pumps are among the most energy efficient technologies for providing HVAC and water heating. Geothermal heat pump systems are reasonably warranted by manufacturers, and their life is estimated at 25 years for inside components. As of 2004, there are over a million units installed worldwide providing 12 GW of thermal capacity, some confusion exists with regard to the terminology of heat pumps and the use of the term geothermal. Geothermal derives from the Greek and means Earth heat - which geologists and many laymen understand as describing hot rocks, the heat pump was described by Lord Kelvin in 1853 and developed by Peter Ritter von Rittinger in 1855. After experimenting with a freezer, Robert C. Webber built the first direct exchange heat pump in the late 1940s. The first successful project was installed in the Commonwealth Building in 1948. The technology became popular in Sweden in the 1970s, and has been growing slowly in worldwide acceptance since then, open loop systems dominated the market until the development of polybutylene pipe in 1979 made closed loop systems economically viable. As of 2004, there are over a million units installed worldwide providing 12 GW of thermal capacity, each year, about 80,000 units are installed in the US and 27,000 in Sweden
6.
Low-carbon power
–
Low-carbon power comes from processes or technologies that, produce power with substantially lower amounts of carbon dioxide emissions than is emitted from conventional fossil fuel power generation. It includes low power generation sources such as wind power, solar power, hydropower and, including fuel preparation and decommissioning. Over the past 30 years, significant findings regarding global warming highlighted the need to curb carbon emissions, from this, the idea for low carbon power was born. The IPCC has continued to provide scientific, technical and socio-economic advice to the community, through its periodic assessment reports. The historical event set the precedence for introduction of low carbon power technology. The Swedish utility Vattenfall did a study of life cycle emissions of nuclear, hydro, coal, gas, peat. The result of the concluded that the grams of CO2 per kWh of electricity by source is nuclear, hydroelectric, wind, natural gas, peat. The studies surveyed included the 1997 Vattenfall comparative emissions study, among others, sovacools analysis calculated that the mean value of emissions over the lifetime of a nuclear power plant is 66 g/kWh. Comparative results for power, hydroelectricity, solar thermal power. Sovacools analysis has been criticized for poor methodology and data selection, a 2012 life cycle assessment review by Yale University said that depending on conditions, median life cycle GHG emissions could be 9 to 110 g CO2-eq/kWh by 2050. It stated, The collective LCA literature indicates that life cycle GHG emissions from power are only a fraction of traditional fossil sources. Some options, such as power and solar power, produce low quantities of total life cycle carbon emissions. As the single largest emitter of carbon dioxide in the United States, the industry accounted for 39% of CO2 emissions in 2004. Technologies to produce power with low-carbon emissions are already in use at various scales. Together, they account for roughly 28% of all U. S. electric-power production, with nuclear power representing the majority, however, demand for power is increasing, driven by increased population and per capita demand, and low carbon power can supplement the supply needed. Which was published in the peer reviewed journal Energy in 2013, the uncorrected for their intermittency EROEI for each energy source analyzed is as depicted in the attached table at right. While the buffered EROEI stated in the paper for all low carbon sources, with the exception of nuclear. Although the methodological integrity of this paper was challenged by, Marco Raugei, hydroelectric plants have the advantage of being long-lived and many existing plants have operated for more than 100 years
7.
Microgeneration
–
It differs from micropower in that it is principally concerned with fixed power plants rather than for use with mobile devices. Microgeneration technologies include small-scale wind turbines, micro hydro, solar PV systems, microbial fuel cells, ground source heat pumps and these technologies are often combined to form a hybrid power solution that can offer superior performance and lower cost than a system based on one generator. In addition to the electricity plant, infrastructure for energy storage and power conversion. Although a hookup to the electricity grid is not essential. In the developing world however, the start-up cost for this equipment is too high, thus leaving no choice. The whole is sometimes referred to as power conditioning equipment groundings, transfer switches or isolator switches. The whole is sometimes referred to as safety equipment Usually, in microgeneration for homes in the developing world. Simplified house-wiring boxes and cables, known as wiring harnesses, can simply be bought, as such, even people without technical expertise are able to install them. In addition, they are comparatively cheap and offer safety advantages. Battery meters, and meters for power consumption and electricity provision to the power grid With wind turbines. A new wind energy technology is being developed that converts energy from wind energy vibrations to electricity and this energy, called Vibro-Wind technology, can use winds of less strength than normal wind turbines, and can be placed in almost any location. A prototype consisted of a panel mounted with oscillators made out of pieces of foam, the conversion from mechanical to electrical energy is done using a piezoelectric transducer, a device made of a ceramic or polymer that emits electrons when stressed. The building of prototype was led by Francis Moon, professor of mechanical. Moons work in Vibro-Wind Technology was funded by the Atkinson Center for a Sustainable Future at Cornell, for safety, grid-connected set-ups must automatically switch off or enter an anti-islanding mode when there is a failure of the mains power supply. For more about this, see the article on the condition of islanding, depending on the set-up chosen, prices may vary. According to Practical Action, microgeneration at home which uses the latest in cost saving-technology the household expenditure can be extremely low-cost, in fact, Practical Action mentions that many households in farming communities in the developing world spend less than $1 for electricity per month. However, if matters are handled less economically, costs will be dramatically higher, in the UK, the government offers both grants and feedback payments to help businesses, communities and private homes to install these technologies. Community organisations can also receive up to £200,000 in grant funding, grid parity occurs when an alternative energy source can generate electricity at a levelized cost that is less than or equal to the price of purchasing power from the electricity grid
8.
Passive solar building design
–
In passive solar building design, windows, walls, and floors are made to collect, store, and distribute solar energy in the form of heat in the winter and reject solar heat in the summer. This is called passive solar design because, unlike active solar heating systems, the key to design a passive solar building is to best take advantage of the local climate performing an accurate site analysis. Elements to be considered include window placement and size, and glazing type, thermal insulation, thermal mass, Passive solar design techniques can be applied most easily to new buildings, but existing buildings can be adapted or retrofitted. Passive solar technologies use sunlight without active mechanical systems, such technologies convert sunlight into usable heat, cause air-movement for ventilating, or future use, with little use of other energy sources. A common example is a solarium on the equator-side of a building, Passive cooling is the use of the same design principles to reduce summer cooling requirements. Low-grade energy needs, such as space and water heating, have proven over time to be better applications for use of solar energy. In fact, passive-solar design features such as a greenhouse/sunroom/solarium can greatly enhance the livability, daylight, views, much has been learned about passive solar building design since the 1970s energy crisis. Many unscientific, intuition-based expensive construction experiments have attempted and failed to achieve zero energy - the total elimination of heating-and-cooling energy bills, one of the most useful post-construction evaluation tools has been the use of thermography using digital thermal imaging cameras for a formal quantitative scientific energy audit. Thermal imaging can be used to document areas of thermal performance such as the negative thermal impact of roof-angled glass or a skylight on a cold winter night or hot summer day. The scientific lessons learned over the last three decades have been captured in sophisticated comprehensive building energy simulation computer software systems, scientific passive solar building design with quantitative cost benefit product optimization is not easy for a novice. The economic motivation for design and engineering is significant. If it had been applied comprehensively to new building construction beginning in 1980, America could be saving over $250,000,000 per year on expensive energy, the ability to achieve these goals simultaneously is fundamentally dependent on the seasonal variations in the suns path throughout the day. This occurs as a result of the inclination of the Earths axis of rotation in relation to its orbit, the sun path is unique for any given latitude. In Northern Hemisphere non-tropical latitudes farther than 23, in equatorial regions at less than 23.5 degrees, the position of the sun at solar noon will oscillate from north to south and back again during the year. The 47-degree difference in the altitude of the sun at solar noon between winter and summer forms the basis of solar design. By strategic placement of such as glazing and shading devices. Movable shutters, shades, shade screens, or window quilts can accommodate day-to-day and hour-to-hour solar gain, careful arrangement of rooms completes the passive solar design. A common recommendation for residential dwellings is to place living areas facing solar noon, a heliodon is a traditional movable light device used by architects and designers to help model sun path effects
9.
Renewable energy
–
Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy often provides energy in four important areas, electricity generation, air and water heating/cooling, transportation, based on REN21s 2016 report, renewables contributed 19. 2% to humans global energy consumption and 23. 7% to their generation of electricity in 2014 and 2015, respectively. This energy consumption is divided as 8. 9% coming from biomass,4. 2% as heat energy,3. 9% hydro electricity and 2. 2% is electricity from wind, solar, geothermal. Worldwide investments in renewable technologies amounted to more than US$286 billion in 2015, with countries like China, globally, there are an estimated 7.7 million jobs associated with the renewable energy industries, with solar photovoltaics being the largest renewable employer. As of 2015 worldwide, more than half of all new electricity capacity installed was renewable, Renewable energy resources exist over wide geographical areas, in contrast to other energy sources, which are concentrated in a limited number of countries. Rapid deployment of energy and energy efficiency is resulting in significant energy security, climate change mitigation. In international public opinion there is strong support for promoting renewable sources such as solar power. At the national level, at least 30 nations around the already have renewable energy contributing more than 20 percent of energy supply. National renewable energy markets are projected to continue to grow strongly in the coming decade, for example, in Denmark the government decided to switch the total energy supply to 100% renewable energy by 2050. While many renewable energy projects are large-scale, renewable technologies are also suited to rural and remote areas and developing countries, United Nations Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. Renewable energy systems are becoming more efficient and cheaper. Their share of energy consumption is increasing. Growth in consumption of coal and oil could end by 2020 due to increased uptake of renewables, in its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, rapid deployment of renewable energy and energy efficiency, and technological diversification of energy sources, would result in significant energy security and economic benefits. New government spending, regulation and policies helped the industry weather the financial crisis better than many other sectors. As of 2011, small solar PV systems provide electricity to a few million households, United Nations Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. At the national level, at least 30 nations around the already have renewable energy contributing more than 20% of energy supply. Some countries have much higher long-term policy targets of up to 100% renewables, outside Europe, a diverse group of 20 or more other countries target renewable energy shares in the 2020–2030 time frame that range from 10% to 50%
10.
Anaerobic digestion
–
Anaerobic digestion is a collection of processes by which microorganisms break down biodegradable material in the absence of oxygen. The process is used for industrial or domestic purposes to waste or to produce fuels. Much of the fermentation used industrially to produce food and drink products, as well as home fermentation, anaerobic digestion occurs naturally in some soils and in lake and oceanic basin sediments, where it is usually referred to as anaerobic activity. This is the source of marsh gas methane as discovered by Volta in 1776, the digestion process begins with bacterial hydrolysis of the input materials. Insoluble organic polymers, such as carbohydrates, are broken down to soluble derivatives that become available for other bacteria, acidogenic bacteria then convert the sugars and amino acids into carbon dioxide, hydrogen, ammonia, and organic acids. These bacteria convert these resulting organic acids into acetic acid, along with ammonia, hydrogen. Finally, methanogens convert these products to methane and carbon dioxide, the methanogenic archaea populations play an indispensable role in anaerobic wastewater treatments. Anaerobic digestion is used as part of the process to treat biodegradable waste, as part of an integrated waste management system, anaerobic digestion reduces the emission of landfill gas into the atmosphere. Anaerobic digesters can also be fed with energy crops, such as maize. Anaerobic digestion is used as a source of renewable energy. The process produces a biogas, consisting of methane, carbon dioxide and this biogas can be used directly as fuel, in combined heat and power gas engines or upgraded to natural gas-quality biomethane. The nutrient-rich digestate also produced can be used as fertilizer, many microorganisms affect anaerobic digestion, including acetic acid-forming bacteria and methane-forming archaea. These organisms promote a number of processes in converting the biomass to biogas. Gaseous oxygen is excluded from the reactions by physical containment, anaerobes utilize electron acceptors from sources other than oxygen gas. These acceptors can be the material itself or may be supplied by inorganic oxides from within the input material. When the oxygen source in a system is derived from the organic material itself, the intermediate end products are primarily alcohols, aldehydes. In the presence of specialised methanogens, the intermediates are converted to the end products of methane, carbon dioxide. In an anaerobic system, the majority of the energy contained within the starting material is released by methanogenic bacteria as methane
11.
Biofuel
–
Biofuels can be derived directly from plants, or indirectly from agricultural, commercial, domestic, and/or industrial wastes. Renewable biofuels generally involve contemporary carbon fixation, such as those that occur in plants or microalgae through the process of photosynthesis, other renewable biofuels are made through the use or conversion of biomass. This biomass can be converted to convenient energy-containing substances in three different ways, thermal conversion, chemical conversion, and biochemical conversion and this biomass conversion can result in fuel in solid, liquid, or gas form. This new biomass can also be used directly for biofuels, bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in sugar or starch crops such as corn, sugarcane, or sweet sorghum. Cellulosic biomass, derived from sources, such as trees and grasses, is also being developed as a feedstock for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form, bioethanol is widely used in the USA and in Brazil. Current plant design does not provide for converting the portion of plant raw materials to fuel components by fermentation. Biodiesel is produced from oils or fats using transesterification and is the most common biofuel in Europe, in 2010, worldwide biofuel production reached 105 billion liters, up 17% from 2009, and biofuels provided 2. 7% of the worlds fuels for road transport. Global ethanol fuel production reached 86 billion liters in 2010, with the United States and Brazil as the top producers. The worlds largest biodiesel producer is the European Union, accounting for 53% of all production in 2010. As of 2011, mandates for blending biofuels exist in 31 countries at the national level, the International Energy Agency has a goal for biofuels to meet more than a quarter of world demand for transportation fuels by 2050 to reduce dependence on petroleum and coal. The production of biofuels also led into an automotive industry. There are various social, economic, environmental and technical issues relating to production and use. Most transportation fuels are liquids, because vehicles usually require high energy density and this occurs naturally in liquids and solids. High energy density can also be provided by a combustion engine. The fuels that are easiest to burn cleanly are typically liquids, thus, liquids meet the requirements of being both energy-dense and clean-burning. In addition, liquids can be pumped, which means handling is easily mechanized, first-generation or conventional biofuels are made from sugar, starch, or vegetable oil. Biobutanol is often claimed to provide a replacement for gasoline
12.
Geothermal power
–
Geothermal power is power generated by geothermal energy. Technologies in use include dry steam power stations, flash steam power stations, Geothermal electricity generation is currently used in 24 countries, while geothermal heating is in use in 70 countries. As of 2015, worldwide geothermal power capacity amounts to 12.8 gigawatts, International markets grew at an average annual rate of 5 percent over the last three years and global geothermal power capacity is expected to reach 14. 5–17.6 GW by 2020. Countries generating more than 15 percent of their electricity from geothermal sources include El Salvador, Kenya, Geothermal power is considered to be a sustainable, renewable source of energy because the heat extraction is small compared with the Earths heat content. In the 20th century, demand for electricity led to the consideration of geothermal power as a generating source, prince Piero Ginori Conti tested the first geothermal power generator on 4 July 1904 in Larderello, Italy. It successfully lit four light bulbs, later, in 1911, the worlds first commercial geothermal power station was built there. Experimental generators were built in Beppu, Japan and the Geysers, California, in the 1920s, in 1958, New Zealand became the second major industrial producer of geothermal electricity when its Wairakei station was commissioned. Wairakei was the first station to use flash steam technology, in 1960, Pacific Gas and Electric began operation of the first successful geothermal electric power station in the United States at The Geysers in California. The original turbine lasted for more than 30 years and produced 11 MW net power, the binary cycle power station was first demonstrated in 1967 in Russia and later introduced to the USA in 1981, following the 1970s energy crisis and significant changes in regulatory policies. This technology allows the use of lower temperature resources than were previously recoverable. In 2006, a binary cycle station in Chena Hot Springs, Alaska, came on-line, Geothermal electric stations have until recently been built exclusively where high temperature geothermal resources are available near the surface. The development of binary cycle power plants and improvements in drilling, demonstration projects are operational in Landau-Pfalz, Germany, and Soultz-sous-Forêts, France, while an earlier effort in Basel, Switzerland was shut down after it triggered earthquakes. Other demonstration projects are under construction in Australia, the United Kingdom, the thermal efficiency of geothermal electric stations is low, around 7–10%, because geothermal fluids are at a low temperature compared with steam from boilers. By the laws of thermodynamics this low temperature limits the efficiency of engines in extracting useful energy during the generation of electricity. Exhaust heat is wasted, unless it can be used directly and locally, for example in greenhouses, timber mills, and district heating. The efficiency of the system does not affect operational costs as it would for a coal or other fossil fuel plant, in order to produce more energy than the pumps consume, electricity generation requires high temperature geothermal fields and specialized heat cycles. Because geothermal power does not rely on sources of energy, unlike, for example, wind or solar. However the global average capacity factor was 74. 5% in 2008, the earth’s heat content is about 1031 joules
13.
Hydroelectricity
–
Hydroelectricity is electricity produced from hydropower. In 2015 hydropower generated 16. 6% of the total electricity and 70% of all renewable electricity. Hydropower is produced in 150 countries, with the Asia-Pacific region generating 33 percent of global hydropower in 2013, China is the largest hydroelectricity producer, with 920 TWh of production in 2013, representing 16.9 percent of domestic electricity use. The cost of hydroelectricity is relatively low, making it a source of renewable electricity. The hydro station consumes no water, unlike coal or gas plants, the average cost of electricity from a hydro station larger than 10 megawatts is 3 to 5 U. S. cents per kilowatt-hour. With a dam and reservoir it is also a source of electricity since the amount produced by the station can be changed up or down very quickly to adapt to changing energy demands. Once a hydroelectric complex is constructed, the project produces no direct waste, Hydropower has been used since ancient times to grind flour and perform other tasks. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique which described vertical-, by the late 19th century, the electrical generator was developed and could now be coupled with hydraulics. The growing demand for the Industrial Revolution would drive development as well, in 1878 the worlds first hydroelectric power scheme was developed at Cragside in Northumberland, England by William George Armstrong. It was used to power an arc lamp in his art gallery. The old Schoelkopf Power Station No.1 near Niagara Falls in the U. S. side began to produce electricity in 1881. The first Edison hydroelectric power station, the Vulcan Street Plant, began operating September 30,1882, in Appleton, Wisconsin, by 1886 there were 45 hydroelectric power stations in the U. S. and Canada. By 1889 there were 200 in the U. S. alone, at the beginning of the 20th century, many small hydroelectric power stations were being constructed by commercial companies in mountains near metropolitan areas. Grenoble, France held the International Exhibition of Hydropower and Tourism with over one million visitors, by 1920 as 40% of the power produced in the United States was hydroelectric, the Federal Power Act was enacted into law. The Act created the Federal Power Commission to regulate hydroelectric power stations on federal land, as the power stations became larger, their associated dams developed additional purposes to include flood control, irrigation and navigation. Federal funding became necessary for development and federally owned corporations, such as the Tennessee Valley Authority. Hydroelectric power stations continued to become larger throughout the 20th century, Hydropower was referred to as white coal for its power and plenty. Hoover Dams initial 1,345 MW power station was the worlds largest hydroelectric station in 1936
14.
Solar energy
–
Active solar techniques include the use of photovoltaic systems, concentrated solar power and solar water heating to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light-dispersing properties, the large magnitude of solar energy available makes it a highly appealing source of electricity. The United Nations Development Programme in its 2000 World Energy Assessment found that the potential of solar energy was 1. This is several times larger than the world energy consumption. In 2011, the International Energy Agency said that the development of affordable, inexhaustible, hence the additional costs of the incentives for early deployment should be considered learning investments, they must be wisely spent and need to be widely shared. The Earth receives 174,000 terawatts of incoming solar radiation at the upper atmosphere, approximately 30% is reflected back to space while the rest is absorbed by clouds, oceans and land masses. The spectrum of light at the Earths surface is mostly spread across the visible. Most of the population live in areas with insolation levels of 150-300 watts/m². Solar radiation is absorbed by the Earths land surface, oceans – which cover about 71% of the globe –, warm air containing evaporated water from the oceans rises, causing atmospheric circulation or convection. When the air reaches an altitude, where the temperature is low, water vapor condenses into clouds. The latent heat of water condensation amplifies convection, producing atmospheric phenomena such as wind, sunlight absorbed by the oceans and land masses keeps the surface at an average temperature of 14 °C. By photosynthesis, green plants convert solar energy into stored energy, which produces food, wood. The total solar energy absorbed by Earths atmosphere, oceans and land masses is approximately 3,850,000 exajoules per year, in 2002, this was more energy in one hour than the world used in one year. Photosynthesis captures approximately 3,000 EJ per year in biomass, geography affects solar energy potential because areas that are closer to the equator have a greater amount of solar radiation. However, the use of photovoltaics that can follow the position of the sun can significantly increase the energy potential in areas that are farther from the equator. Time variation effects the potential of energy because during the nighttime there is little solar radiation on the surface of the Earth for solar panels to absorb. This limits the amount of energy that solar panels can absorb in one day, cloud cover can affect the potential of solar panels because clouds block incoming light from the sun and reduce the light available for solar cells. In addition, land availability has an effect on the available solar energy because solar panels can only be set up on land that is otherwise unused
15.
Tidal power
–
Tidal power or tidal energy is a form of hydropower that converts the energy obtained from tides into useful forms of power, mainly electricity. Although not yet used, tidal power has potential for future electricity generation. Tides are more predictable than wind energy and solar power, historically, tide mills have been used both in Europe and on the Atlantic coast of North America. The incoming water was contained in large ponds, and as the tide went out. The earliest occurrences date from the Middle Ages, or even from Roman times, the process of using falling water and spinning turbines to create electricity was introduced in the U. S. and Europe in the 19th century. The worlds first large-scale tidal power plant was the Rance Tidal Power Station in France and it was the largest tidal power station in terms of output until Sihwa Lake Tidal Power Station opened in South Korea in August,2011. The Sihwa station uses sea wall defense barriers complete with 10 turbines generating 254 MW, Tidal power is taken from the Earths oceanic tides. Tidal forces are periodic variations in gravitational attraction exerted by celestial bodies and these forces create corresponding motions or currents in the worlds oceans. Due to the attraction to the oceans, a bulge in the water level is created. When the sea level is raised, water from the middle of the ocean is forced to move toward the shorelines and this occurrence takes place in an unfailing manner, due to the consistent pattern of the moon’s orbit around the earth. Tidal power is the technology that draws on energy inherent in the orbital characteristics of the Earth–Moon system. Other natural energies exploited by human technology originate directly or indirectly with the Sun, including fuel, conventional hydroelectric, wind, biofuel, wave. A tidal generator converts the energy of tidal flows into electricity, greater tidal variation and higher tidal current velocities can dramatically increase the potential of a site for tidal electricity generation. This loss of energy has caused the rotation of the Earth to slow in the 4.5 billion years since its formation. During the last 620 million years the period of rotation of the earth has increased from 21.9 hours to 24 hours, while tidal power will take additional energy from the system, the effect is negligible and would only be noticed over millions of years. Some tidal generators can be built into the structures of existing bridges or are entirely submersed, land constrictions such as straits or inlets can create high velocities at specific sites, which can be captured with the use of turbines. These turbines can be horizontal, vertical, open, or ducted, Tidal barrages make use of the potential energy in the difference in height between high and low tides. When using tidal barrages to generate power, the energy from a tide is seized through strategic placement of specialized dams
16.
Wave power
–
Wave power is the transport of energy by wind waves, and the capture of that energy to do useful work – for example, electricity generation, water desalination, or the pumping of water. A machine able to exploit wave power is known as a wave energy converter. Wave power is distinct from the flux of tidal power. Wave-power generation is not currently a widely employed commercial technology, although there have been attempts to use it since at least 1890, in 2008, the first experimental wave farm was opened in Portugal, at the Aguçadoura Wave Park. Waves are generated by passing over the surface of the sea. As long as the waves propagate slower than the speed just above the waves. Wave height is determined by speed, the duration of time the wind has been blowing, fetch and by the depth. A given wind speed has a practical limit over which time or distance will not produce larger waves. When this limit has been reached the sea is said to be fully developed, in general, larger waves are more powerful but wave power is also determined by wave speed, wavelength, and water density. Oscillatory motion is highest at the surface and diminishes exponentially with depth, however, for standing waves near a reflecting coast, wave energy is also present as pressure oscillations at great depth, producing microseisms. These pressure fluctuations at greater depth are too small to be interesting from the point of view of wave power, the waves propagate on the ocean surface, and the wave energy is also transported horizontally with the group velocity. The mean transport rate of the energy through a vertical plane of unit width. The above formula states that power is proportional to the wave energy period. When the significant wave height is given in metres, and the period in seconds. Example, Consider moderate ocean swells, in water, a few km off a coastline, with a wave height of 3 m. Using the formula to solve for power, we get P ≈0.5 kW m 3 ⋅ s 2 ≈36 kW m, in major storms, the largest waves offshore are about 15 meters high and have a period of about 15 seconds. According to the formula, such waves carry about 1.7 MW of power across each metre of wavefront. An effective wave power device captures as much as possible of the energy flux
17.
Wind power
–
Wind power is the use of air flow through wind turbines to mechanically power generators for electric power. The net effects on the environment are far less problematic than those of power sources. Wind farms consist of individual wind turbines which are connected to the electric power transmission network. Onshore wind is a source of electric power, competitive with or in many places cheaper than coal or gas plants. Offshore wind is steadier and stronger than on land, and offshore farms have less visual impact, small onshore wind farms can feed some energy into the grid or provide electric power to isolated off-grid locations. Wind power gives variable power which is consistent from year to year. It is therefore used in conjunction with other power sources to give a reliable supply. As the proportion of power in a region increases, a need to upgrade the grid. In addition, weather forecasting permits the power network to be readied for the predictable variations in production that occur. As of 2015, Denmark generates 40% of its power from wind. In 2014 global wind power capacity expanded 16% to 369,553 MW, yearly wind energy production is also growing rapidly and has reached around 4% of worldwide electric power usage,11. 4% in the EU. Wind power has been used as long as humans have put sails into the wind, for more than two millennia wind-powered machines have ground grain and pumped water. Wind power was available and not confined to the banks of fast-flowing streams, or later. Wind-powered pumps drained the polders of the Netherlands, and in regions such as the American mid-west or the Australian outback, wind pumps provided water for live stock. The first windmill used for the production of power was built in Scotland in July 1887 by Prof James Blyth of Andersons College. Blyth offered the surplus power to the people of Marykirk for lighting the main street, however. The Brush wind turbine had a rotor 17 metres in diameter and was mounted on an 18 metres tower, although large by todays standards, the machine was only rated at 12 kW. The connected dynamo was used either to charge a bank of batteries or to operate up to 100 incandescent light bulbs, with the development of electric power, wind power found new applications in lighting buildings remote from centrally-generated power
18.
Sustainable transport
–
Components for evaluating sustainability include the particular vehicles used for road, water or air transport, the source of energy, and the infrastructure used to accommodate the transport. Another component for evaluation is pipelines for transporting liquid or gas materials, Transport operations and logistics as well as transit-oriented development are also involved in evaluation. Transportation sustainability is largely being measured by transportation system effectiveness and efficiency as well as the environmental, the entire life cycle of transport systems is subject to sustainability measurement and optimization. Sustainable transport systems make a contribution to the environmental, social. The advantages of increased mobility need to be weighed against the environmental, social, Transport systems have significant impacts on the environment, accounting for between 20% and 25% of world energy consumption and carbon dioxide emissions. The majority of the emissions, almost 97%, came from burning of fossil fuels. Greenhouse gas emissions from transport are increasing at a faster rate than any other energy using sector, road transport is also a major contributor to local air pollution and smog. The United Nations Environment Programme estimates that each year 2.4 million premature deaths from air pollution could be avoided. The social costs of transport include road crashes, air pollution, physical inactivity, time taken away from the family while commuting, many of these negative impacts fall disproportionately on those social groups who are also least likely to own and drive cars. Traffic congestion imposes economic costs by wasting time and by slowing the delivery of goods. Traditional transport planning aims to improve mobility, especially for vehicles, communities which are successfully improving the sustainability of their transport networks are doing so as part of a wider programme of creating more vibrant, livable, sustainable cities. There are many definitions of the transport, and of the related terms sustainable transportation. Is Affordable, operates fairly and efficiently, offers a choice of transport mode, Sustainability extends beyond just the operating efficiency and emissions. A Life-cycle assessment involves production, use and post-use considerations, a cradle-to-cradle design is more important than a focus on a single factor such as energy efficiency. Most of the tools and concepts of sustainable transport were developed before the phrase was coined, walking, the first mode of transport, is also the most sustainable. Public transport dates back at least as far as the invention of the bus by Blaise Pascal in 1662. The first passenger tram began operation in 1807 and the first passenger service in 1825. Pedal bicycles date from the 1860s and these were the only personal transport choices available to most people in Western countries prior to World War II, and remain the only options for most people in the developing world
19.
Carbon-neutral fuel
–
Carbon-neutral fuels can refer to a variety of energy fuels or energy systems which have no net greenhouse gas emissions or carbon footprint. One class is synthetic fuel produced from sustainable or nuclear energy used to hydrogenate carbon dioxide recycled from power plant flue exhaust gas or derived from carbonic acid in seawater. Other types can be produced from renewable sources such as wind turbines, solar panels. Such fuels are potentially carbon-neutral because they do not result in a net increase in greenhouse gases. Until captured carbon is used for plastics feedstock, carbon neutral fuel synthesis is the means of carbon capture. A250 kilowatt synthetic methane plant has been built in Germany, the fuel, often referred to as electrofuel, stores the energy that was used in the production of the hydrogen. Coal can also be used to produce the hydrogen, but that would not be a carbon-neutral source, Carbon dioxide can be captured and buried, making fossil fuels carbon-neutral, although not renewable. Carbon capture from exhaust gas can make carbon-neutral fuels carbon negative, other hydrocarbons can be broken down to produce hydrogen and carbon dioxide which could then be stored while the hydrogen is used for energy or fuel, which would also be carbon-neutral. The most energy-efficient fuel to produce is methanol, which is made from a reaction of a carbon-dioxide molecule with three hydrogen molecules to produce methanol and water. The stored energy can be recovered by burning the methanol in an engine, releasing carbon dioxide, water. Methane can be produced in a similar reaction, more energy can be used to combine methanol or methane into larger hydrocarbon fuel molecules. Researchers have also suggested using methanol to produce dimethyl ether and this fuel could be used as a substitute for diesel fuel due to its ability to self ignite under high pressure and temperature. It is already being used in areas for heating and energy generation. It is nontoxic, but must be stored under pressure, octane and ethanol can also be produced from carbon dioxide and hydrogen. All synthetic hydrocarbons are generally produced at temperatures of 200–300 °C, catalysts are usually used to improve the efficiency of the reaction and create the desired type of hydrocarbon fuel. Such reactions are exothermic and use about 3 mol of hydrogen per mole of carbon dioxide involved and they also produce large amounts of water as a byproduct. The most economical source of carbon for recycling into fuel is flue-gas emissions from fossil-fuel combustion where it can be obtained for about USD $7.50 per ton, automobile exhaust gas capture has also been seen as economical but would require extensive design changes or retrofitting. Since carbonic acid in seawater is in equilibrium with atmospheric carbon dioxide
20.
Electric vehicle
–
An electric vehicle, also referred to as an electric drive vehicle, uses one or more electric motors or traction motors for propulsion. EVs include road and rail vehicles, surface and underwater vessels, electric aircraft, in the 21st century, EVs saw a resurgence due to technological developments and an increased focus on renewable energy. Government incentives to increase adoptions were introduced, including in the United States, around the same period, early experimental electrical cars were moving on rails, too. American blacksmith and inventor Thomas Davenport built a toy electric locomotive, powered by an electric motor. In 1838, a Scotsman named Robert Davidson built a locomotive that attained a speed of four miles per hour. In England a patent was granted in 1840 for the use of rails as conductors of electric current, between 1832 and 1839, Robert Anderson of Scotland invented the first crude electric carriage, powered by non-rechargeable primary cells. By the 20th century, electric cars and rail transport were commonplace, electrified trains were used for coal transport, as the motors did not use precious oxygen in the mines. Switzerlands lack of fossil resources forced the rapid electrification of their rail network. One of the earliest rechargeable batteries - the nickel-iron battery - was favored by Edison for use in electric cars and they were produced by Baker Electric, Columbia Electric, Detroit Electric, and others, and at one point in history out-sold gasoline-powered vehicles. In fact, in 1900,28 percent of the cars on the road in the USA were electric, EVs were so popular that even President Woodrow Wilson and his secret service agents toured Washington DC in their Milburn Electrics, which covered 60–70 mi per charge. A number of developments contributed to decline of electric cars, as roads were improved outside urban areas electric vehicle range could not compete with the ICE. Finally, the initiation of production of gasoline-powered vehicles by Henry Ford in 1913 reduced significantly the cost of gasoline cars as compared to electric cars. In January 1990, General Motors President introduced its EV concept two-seater and that September, the California Air Resources Board mandated major-automaker sales of EVs, in phases starting in 1998. From 1996 to 1998 GM produced 1117 EV1s,800 of which were available through three-year leases. Chrysler, Ford, GM, Honda, Nissan and Toyota also produced limited numbers of EVs for California drivers, in 2003, upon the expiration of GMs EV1 leases, GM crushed them. A movie made on the subject in 2005-2006 was titled Who Killed the Electric Car. Ford released a number of their Ford Ecostar delivery vans into the market. Honda, Nissan and Toyota also repossessed and crushed most of their EVs, after public protests, Toyota sold 200 of its RAV EVs to eager buyers, they later sold at over their original forty-thousand-dollar price. This lesson did not go unlearned, BMW of Canada sold off a number of Mini EVs when their Canadian testing ended, the production of the Citroën Berlingo Electrique stopped in September 2005
21.
Fossil fuel phase-out
–
Its purpose is to reduce air pollution, mining tragedies, and greenhouse gas emissions which cause climate change. A move to the forms of renewable energy or nuclear energy is involved in shifting away from fossil fuels. New EPA initiatives targeting air toxics, coal ash, and effluent releases highlight the environmental impacts of coal, the use of fracking in natural gas exploration is coming under scrutiny, with evidence of groundwater contamination and greenhouse gas emissions. Concerns are increasing about the vast amounts of water used at coal-fired and nuclear power plants, events at the Fukushima nuclear plant have renewed doubts about the ability to operate large numbers of nuclear plants safely over the long term. Further, cost estimates for next generation nuclear units continue to climb, in 2008, James Hansen and nine other scientists published a journal article titled Target atmospheric CO2, Where should humanity aim. Which calls for a complete phase-out of coal power by 2030, More recently, Hansen has stated that continued opposition to nuclear power threatens humanitys ability to avoid dangerous climate change. The letter, co-authored with other climate change experts declared If we stay on the current path, he said, the best candidate to avoid that is nuclear power. We need to take advantage of it, and Continued opposition to nuclear power threatens humanitys ability to avoid dangerous climate change. Also in 2008, Pushker Kharecha and James Hansen published a scientific study analyzing the effect of a coal phase-out on atmospheric carbon dioxide levels. Their baseline mitigation scenario was a phaseout of coal emissions by 2050. Between 2025 and 2050 it is assumed that developed and developing countries will linearly phase out emissions of CO2 from coal usage. These rates refer to emissions to the atmosphere and do not constrain consumption of coal, oil and gas emissions are assumed to be the same as in the BAU scenario. Under the Business as Usual scenario, atmospheric CO2 peaks at 563 parts per million in the year 2100, under the four coal phase-out scenarios, atmospheric CO2 peaks at 422-446 ppm between 2045 and 2060 and declines thereafter. In the Greenpeace and ERECs Energy evolution scenario, the world would eliminate all fossil fuel use by 2090, in December 2015 Greenpeace and Climate Action Network Europe released a report highlighting the need for an active phase-out of coal-fired generation across Europe. Their analysis derived from a database of 280 coal plants and included data from official EU registries. 5 °C goal. The report observes that one of the most powerful climate policy levers is also the simplest, the report concludes that, on the whole, building coal-fired power plants does little to help the poor and may make them poorer. Moreover, wind and solar generation are beginning to challenge coal on cost, Coal is one of the largest sources of energy, supplying 27 percent of the worlds primary energy in 2006. Coal also accounts for up to one-third of global carbon emissions, to decrease carbon emissions and thus possibly stop extreme climate change, some have called for coal to be phased out
22.
Green vehicle
–
As part of their contribution to sustainable transport, these vehicles reduce air pollution and greenhouse gas emissions, and contribute to energy independence by reducing oil imports. An environmental analysis extends beyond just the operating efficiency and emissions, a life-cycle assessment involves production and post-use considerations. A cradle-to-cradle design is more important than a focus on a factor such as energy efficiency. Using biofuels instead of petroleum fuels, proper maintenance of a vehicle such as engine tune-ups, oil changes, and maintaining proper tire pressure can also help. Removing unnecessary items from a vehicle weight and improves fuel economy as well. Green vehicles include vehicles types that function fully or partly on energy sources other than fossil fuel or less carbon intensive than gasoline or diesel. Another option is the use of alternative fuel composition in conventional fossil fuel-based vehicles, other approaches include personal rapid transit, a public transportation concept that offers automated, on-demand, non-stop transportation on a network of specially built guideways. Examples of vehicles with reduced petroleum consumption include electric cars, plug-in hybrids, Electric cars are typically more efficient than fuel cell-powered vehicles on a Tank-to-wheel basis. They have better fuel economy than conventional internal combustion engine vehicles but are hampered by range or maximum distance attainable before discharging the battery, the electric car batteries are their main cost. They provide a 0% to 99. 9% reduction in CO2 emissions compared to an ICE vehicle, Hybrid cars may be partly fossil fuel powered and partly electric or hydrogen-powered. Most combine an internal combustion engine with an engine, though other variations too exist. The internal combustion engine is either a gasoline or Diesel engine. They are more expensive to purchase but cost redemption is achieved in a period of about 5 years due to fuel economy. Compressed air cars, stirling-powered vehicles, Liquid nitrogen vehicles are less polluting than electrical vehicles, as the vehicle. Solar car races are held on a basis in order to promote green vehicles. These sleek driver-only vehicles can travel long distances at highway speeds using only the electricity generated instantaneously from the sun, a conventional vehicle can become a greener vehicle by mixing in renewable fuels or using less carbon intensive fossil fuel. Typical gasoline-powered cars can tolerate up to 10% ethanol, Brazil manufactured cars that run on neat ethanol, though there were discontinued. Another available option is a vehicle which allows any blend of gasoline and ethanol, up to 85% in North America and Europe
23.
Plug-in hybrid
–
Most PHEVs are passenger cars but there are also PHEV versions of commercial vehicles and vans, utility trucks, buses, trains, motorcycles, scooters, and military vehicles. The cost of electricity to power plug-in hybrids for all-electric operation has been estimated at less than one quarter of the cost of gasoline in California, compared to conventional vehicles, PHEVs produce less air pollution locally and require less petroleum. PHEVs may produce less in the way of greenhouse gases, which contribute to global warming, Plug-in hybrids use no fossil fuel at the point of use during their all-electric range. Plug-in hybrids greenhouse-gas emissions, during operation in their all-electric range mode, if the batteries are charged directly from renewable sources off the electrical grid, then the tailpipe greenhouse gas emissions are zero when running only on battery power. Chinese battery manufacturer and automaker BYD Auto released the F3DM to the Chinese fleet market in December 2008, General Motors began delivering the Chevrolet Volt in the United States in December 2010, it was the first electric car with a range extender for retail sale in the American market. As of December 2016, there are over 30 models of highway legal plug-in hybrids for retail sales. Plug-in hybrid cars are mainly in the United States, Canada, Western Europe, Japan. As of December 2016, the Chevrolet Volt family, including its siblings Opel/Vauxhall Ampera, is the worlds best-selling plug-in hybrid in history with combined sales of about 134,500 units. As of December 2016, the stock of plug-in hybrid cars totaled almost 800,000 units. Flexibility in power demand, diverse patterns and storage capability of PHEVs grow the elasticity of residential electricity demand remarkably. This elasticity can be used to form the daily aggregated demand profile and/or alter instantaneous demand of a system wherein a number of residential PHEVs share one electricity retailer. A plug-in hybrids all-electric range is designated by PHEV- or PHEVkm in which the number represents the distance the vehicle can travel on battery power alone, for example, a PHEV-20 can travel twenty miles without using its combustion engine, so it may also be designated as a PHEV32km. This distinguishes PHEVs from regular hybrid cars mass marketed today, which do not use any electricity from the grid, other popular terms sometimes used for plug-in hybrids are grid-connected hybrids, Gas-Optional Hybrid Electric Vehicle or simply gas-optional hybrids. General Motors calls its Chevrolet Volt series plug-in hybrid an Extended-Range Electric Vehicle, the Lohner-Porsche Mixte Hybrid, produced as early as 1899, was the first hybrid electric car. Early hybrids could be charged from an external source before operation, however, the term plug-in hybrid has come to mean a hybrid vehicle that can be charged from a standard electrical wall socket. The term plug-in hybrid electric vehicle was coined by UC Davis Professor Andrew Frank, the July 1969 issue of Popular Science featured an article on the General Motors XP-883 plug-in hybrid. The concept commuter vehicle housed six 12-volt lead–acid batteries in the trunk area, the car could be plugged into a standard North American 120 volt AC outlet for recharging. In 2003, Renault began selling the Electroad, a series hybrid version of their popular Kangoo
24.
Heat engine
–
In thermodynamics, a heat engine is a system that converts heat or thermal energy—and chemical energy—to mechanical energy, which can then be used to do mechanical work. It does this by bringing a working substance from a higher temperature to a lower state temperature. A heat source generates thermal energy that brings the working substance to the high temperature state, the working substance generates work in the working body of the engine while transferring heat to the colder sink until it reaches a low temperature state. During this process some of the energy is converted into work by exploiting the properties of the working substance. The working substance can be any system with a heat capacity. During this process, a lot of heat is lost to the surroundings, in general an engine converts energy to mechanical work. Heat engines distinguish themselves from other types of engines by the fact that their efficiency is limited by Carnots theorem. Since the heat source that supplies energy to the engine can thus be powered by virtually any kind of energy. Heat engines are often confused with the cycles they attempt to implement, typically, the term engine is used for a physical device and cycle for the model. In thermodynamics, heat engines are often modeled using an engineering model such as the Otto cycle. The theoretical model can be refined and augmented with data from an operating engine. Since very few implementations of heat engines exactly match their underlying thermodynamic cycles. In general terms, the larger the difference in temperature between the hot source and the sink, the larger is the potential thermal efficiency of the cycle. The efficiency of heat engines proposed or used today has a large range. 25% for most automotive gasoline engines 49% for a supercritical coal-fired power station such as the Avedøre Power Station, all these processes gain their efficiency from the temperature drop across them. Significant energy may be used for equipment, such as pumps. Heat engines can be characterized by their power, which is typically given in kilowatts per litre of engine displacement. The result offers an approximation of the power output of an engine
25.
Power station
–
A power station, also referred to as a power plant or powerhouse and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Most power stations contain one or more generators, a machine that converts mechanical power into electrical power. The relative motion between a field and a conductor creates an electrical current. The energy source harnessed to turn the generator varies widely, most power stations in the world burn fossil fuels such as coal, oil, and natural gas to generate electricity. Others use nuclear power, but there is an use of cleaner renewable sources such as solar, wind, wave. There is some debate within utility and engineering circles over whether a solar array, or wind farm, should be referred to as a power station, in 1868 a hydro electric power station was designed and built by Lord Armstrong at Cragside, England. It used water from lakes on his estate to power Siemens dynamos, the electricity supplied power to lights, heating, produced hot water, ran an elevator as well as labor-saving devices and farm buildings. In the early 1870s Belgian inventor Zénobe Gramme invented a powerful enough to produce power on a commercial scale for industry. In the autumn of 1882, a central station providing public power was built in Godalming and it was proposed after the town failed to reach an agreement on the rate charged by the gas company, so the town council decided to use electricity. It used hydroelectric power that was used to street and household lighting, the system was not a commercial success and the town reverted to gas. In 1882 a the worlds first coal-fired public power station, the Edison Electric Light Station, was built in London, a Babcock & Wilcox boiler powered a 125-horsepower steam engine that drove a 27-ton generator. This supplied electricity to premises in the area that could be reached through the culverts of the viaduct without digging up the road, the customers included the City Temple and the Old Bailey. Another important customer was the Telegraph Office of the General Post Office, Johnson arranged for the supply cable to be run overhead, via Holborn Tavern and Newgate. In September 1882 in New York, the Pearl Street Station was established by Edison to provide lighting in the lower Manhattan Island area. The station ran until destroyed by fire in 1890, the station used reciprocating steam engines to turn direct-current generators. Because of the DC distribution, the area was small. The War of Currents eventually resolved in favor of AC distribution and utilization, DC systems with a service radius of a mile or so were necessarily smaller, less efficient of fuel consumption, and more labor-intensive to operate than much larger central AC generating stations. AC systems used a range of frequencies depending on the type of load, lighting load using higher frequencies
26.
Electricity generation
–
Electricity generation is the process of generating electric power from sources of primary energy. For electric utilities, it is the first process in the delivery of electricity to consumers, the other processes as transmission, distribution, energy storage and recovery using pumped-storage methods are normally carried out by the electric power industry. Other energy sources include solar photovoltaics and geothermal power, the fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. This method is used today, electricity is generated by the movement of a loop of wire. Central power stations became practical with the development of alternating current power transmission, using power transformers to transmit power at high voltage. Electricity has been generated at central stations since 1882, the use of power-lines and power-poles have been significantly important in the distribution of electricity. There are seven fundamental methods of transforming other forms of energy into electrical energy. Static electricity, form the physical separation and transport of charge and it was the first form discovered and investigated, and the electrostatic generator is still used even in modern devices such as the Van de Graaff generator and MHD generators. In Electromagnetic induction, a generator, dynamo or alternator transforms kinetic energy into electricity. This is the most used form for generating electricity and is based on Faradays law and it can be experimented by rotating a magnet within closed loops of a conducting material. Almost all commercial electrical generation is done using electromagnetic induction, in mechanical energy forces a generator to rotate. Almost all electrical power on Earth is generated with a turbine, driven by wind, water, there are many different methods of developing mechanical energy, including heat engines, hydro, wind and tidal power. Most electric generation is driven by heat engines, the combustion of fossil fuels supplies most of the heat to these engines, with a significant fraction from nuclear fission and some from renewable sources. The modern steam turbine currently generates about 80% of the power in the world using a variety of heat sources. Power sources include, Steam Water is boiled by coal burned in a power plant. Nuclear fission heat created in a nuclear reactor creates steam, less than 15% of electricity is generated this way. Natural gas, turbines are directly by gases produced by combustion. Combined cycle are driven by steam and natural gas
27.
Heat
–
In physics, heat is the amount of energy flowing from one body to another spontaneously due to their temperature difference, or by any means other than through work or the transfer of matter. Thus, energy exchanged as heat during a process changes the energy of each body by equal. The sign of the quantity of heat can indicate the direction of the transfer, for example from system A to system B, negation indicates energy flowing in the opposite direction. While heat flows spontaneously from hot to cold, it is possible to construct a heat pump or refrigeration system that does work to increase the difference in temperature between two systems, conversely, a heat engine reduces an existing temperature difference to do work on another system. Heat is a consequence of the motion of particles. When heat is transferred between two objects or systems, the energy of the object or systems particles increases, as this occurs, the arrangement between particles becomes more and more disordered. In other words, heat is related to the concept of entropy, historically, many energy units for measurement of heat have been used. The standards-based unit in the International System of Units is the joule, Heat is measured by its effect on the states of interacting bodies, for example, by the amount of ice melted or a change in temperature. The quantification of heat via the change of a body is called calorimetry. In calorimetry, sensible heat is defined with respect to a specific chosen state variable of the system, sensible heat causes a change of the temperature of the system while leaving the chosen state variable unchanged. Heat transfer that occurs at a constant system temperature but changes the state variable is called latent heat with respect to the variable, for infinitesimal changes, the total incremental heat transfer is then the sum of the latent and sensible heat. Physicist James Clerk Maxwell, in his 1871 classic Theory of Heat, was one of many who began to build on the established idea that heat has something to do with matter in motion. This was the idea put forth by Benjamin Thompson in 1798. One of Maxwells recommended books was Heat as a Mode of Motion, Maxwell outlined four stipulations for the definition of heat, It is something which may be transferred from one body to another, according to the second law of thermodynamics. It is a quantity, and so can be treated mathematically. It cannot be treated as a substance, because it may be transformed into something that is not a material substance. Heat is one of the forms of energy and this was the way of the historical pioneers of thermodynamics. Maxwell writes that convection as such is not a purely thermal phenomenon, in thermodynamics, convection in general is regarded as transport of internal energy
28.
Syngas
–
Syngas, or synthesis gas, is a fuel gas mixture consisting primarily of hydrogen, carbon monoxide, and very often some carbon dioxide. The name comes from its use as intermediates in creating synthetic natural gas, syngas is usually a product of gasification and the main application is electricity generation. Syngas is combustible and often used as a fuel of internal combustion engines and it has less than half the energy density of natural gas. Syngas can be produced from many sources, including gas, coal, biomass, or virtually any hydrocarbon feedstock, by reaction with steam. Syngas is a crucial resource for production of hydrogen, ammonia, methanol. Syngas is also used as an intermediate in producing synthetic petroleum for use as a fuel or lubricant via the Fischer–Tropsch process and previously the Mobil methanol to gasoline process. Production methods include steam reforming of natural gas or liquid hydrocarbons to produce hydrogen, the gasification of coal, biomass, the chemical composition of syngas varies based on the raw materials and the processes. Syngas produced by coal gasification generally is a mixture of 30 to 60% carbon monoxide,25 to 30% hydrogen,5 to 15% carbon dioxide and it also contains lesser amount of other gases. The main reaction that produces syngas, steam reforming, is a reaction with 206 kJ/mol methane needed for conversion. The first reaction, between incandescent coke and steam, is endothermic, producing carbon monoxide, and hydrogen H2. When the coke bed has cooled to a temperature at which the reaction can no longer proceed. The overall reaction is exothermic, forming producer gas, steam can then be re-injected, then air etc. to give an endless series of cycles until the coke is finally consumed. Producer gas has a lower energy value, relative to water gas. Pure oxygen can be substituted for air to avoid the dilution effect and this is primarily done by pressure swing adsorption, amine scrubbing, and membrane reactors. Conversion of biomass to syngas is typically low-yield, the University of Minnesota developed a metal catalyst that reduces the biomass reaction time by up to a factor of 100. The catalyst can be operated at atmospheric pressure and reduces char, the entire process is autothermic and therefore heating is not required. CO2 can be split into CO and then combined with hydrogen to form syngas and this technique was alleged to have been used during the Cold war in Russian nuclear submarines to allow them to get rid of CO2 gas without leaving a bubble trail. Publicly available journals published during the Cold War indicate that American submarines used conventional chemical scrubbers to remove CO2, documents released after the sinking of the Kursk, a Cold War era Oscar-class submarine, indicate that potassium superoxide scrubbers were used to remove carbon dioxide on that vessel
29.
Hydrogen
–
Hydrogen is a chemical element with chemical symbol H and atomic number 1. With a standard weight of circa 1.008, hydrogen is the lightest element on the periodic table. Its monatomic form is the most abundant chemical substance in the Universe, non-remnant stars are mainly composed of hydrogen in the plasma state. The most common isotope of hydrogen, termed protium, has one proton, the universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, since hydrogen readily forms covalent compounds with most nonmetallic elements, most of the hydrogen on Earth exists in molecular forms such as water or organic compounds. Hydrogen plays an important role in acid–base reactions because most acid-base reactions involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a charge when it is known as a hydride. The hydrogen cation is written as though composed of a bare proton, Hydrogen gas was first artificially produced in the early 16th century by the reaction of acids on metals. Industrial production is mainly from steam reforming natural gas, and less often from more energy-intensive methods such as the electrolysis of water. Most hydrogen is used near the site of its production, the two largest uses being fossil fuel processing and ammonia production, mostly for the fertilizer market, Hydrogen is a concern in metallurgy as it can embrittle many metals, complicating the design of pipelines and storage tanks. Hydrogen gas is flammable and will burn in air at a very wide range of concentrations between 4% and 75% by volume. The enthalpy of combustion is −286 kJ/mol,2 H2 + O2 →2 H2O +572 kJ Hydrogen gas forms explosive mixtures with air in concentrations from 4–74%, the explosive reactions may be triggered by spark, heat, or sunlight. The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C, the detection of a burning hydrogen leak may require a flame detector, such leaks can be very dangerous. Hydrogen flames in other conditions are blue, resembling blue natural gas flames, the destruction of the Hindenburg airship was a notorious example of hydrogen combustion and the cause is still debated. The visible orange flames in that incident were the result of a mixture of hydrogen to oxygen combined with carbon compounds from the airship skin. H2 reacts with every oxidizing element, the ground state energy level of the electron in a hydrogen atom is −13.6 eV, which is equivalent to an ultraviolet photon of roughly 91 nm wavelength. The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, however, the atomic electron and proton are held together by electromagnetic force, while planets and celestial objects are held by gravity. The most complicated treatments allow for the effects of special relativity
30.
Combined cycle
–
By combining these multiple streams of work upon a single mechanical shaft turning an electric generator, the overall net efficiency of the system may be increased by 50–60%. That is, from an efficiency of say 34% to possibly an overall efficiency of 51% in net Carnot thermodynamic efficiency. This can be done because heat engines are able to use a portion of the energy their fuel generates. In an ordinary heat engine the heat from combustion is generally wasted. Combining two or more thermodynamic cycles results in improved efficiency, reducing fuel costs. In stationary power plants, a widely used combination is a gas turbine burning natural gas or synthesis gas from coal, many new gas power plants in North America and Europe are of the Combined Cycle Gas Turbine type. Such an arrangement is used for marine propulsion, and is called a combined gas. Multiple stage turbine or steam cycles are also common, however, it is common in cold climates to drive community heating systems from a power plants condenser heat. Such cogeneration systems can yield theoretical efficiencies above 95%, in automotive and aeronautical engines, turbines have been driven from the exhausts of Otto and Diesel cycles. The thermodynamic cycle of the combined cycle consists of two power plant cycles. One is the Joule or Brayton cycle which is a gas turbine cycle, the cycle 1-2-3-4-1 which is the gas turbine power plant cycle is the topping cycle. It depicts the heat and work transfer process taking place in high temperature region, the cycle a-b-c-d-e-f-a which is the Rankine steam cycle takes place at a low temperature and is known as the bottoming cycle. Transfer of heat energy from high temperature exhaust gas to water, during the constant pressure process 4-1 the exhaust gases in the gas turbine reject heat. The feed water, wet and super heated steam absorb some of this heat in the process a-b, b-c, the steam power plant gets its input heat from the high temperature exhaust gases from gas turbine power plant. The steam generated thus can be used to drive steam turbine, the Waste Heat Recovery Boiler has 3 sections, Economiser, evaporator and superheater. In a thermal station, water is the working medium. High pressure steam requires strong, bulky components, high temperatures require expensive alloys made from nickel or cobalt, rather than inexpensive steel. These alloys limit practical steam temperatures to 655 °C while the temperature of a steam plant is fixed by the temperature of the cooling water
31.
Thermal efficiency
–
For a power cycle, thermal efficiency indicates the extent to which the energy added by heat is converted to net work output. In the case of a refrigeration or heat pump cycle, thermal efficiency indicates the extent to which the energy added by work is converted to net heat output. In general, energy efficiency is the ratio between the useful output of a device and the input, in energy terms. For thermal efficiency, the input, Q i n, to the device is heat, the desired output is mechanical work, W o u t, or heat, Q o u t, or possibly both. Because the input heat normally has a financial cost, a memorable. From the first law of thermodynamics, the output cannot exceed the input, so 0 ≤ η t h <1 When expressed as a percentage. Efficiency is typically less than 100% because there are such as friction. The largest diesel engine in the peaks at 51. 7%. In a combined cycle plant, thermal efficiencies are approaching 60%, such a real-world value may be used as a figure of merit for the device. For engines where a fuel is burned there are two types of efficiency, indicated thermal efficiency and brake thermal efficiency. This efficiency is only appropriate when comparing similar types or similar devices, for other systems the specifics of the calculations of efficiency vary but the non dimensional input is still the same. Efficiency = Output energy / input energy Heat engines transform thermal energy, or heat, Qin into mechanical energy, or work, so the energy lost to the environment by heat engines is a major waste of energy resources. This inefficiency can be attributed to three causes, there is an overall theoretical limit to the efficiency of any heat engine due to temperature, called the Carnot efficiency. Second, specific types of engines have lower limits on their due to the inherent irreversibility of the engine cycle they use. Thirdly, the behavior of real engines, such as mechanical friction. The second law of thermodynamics puts a limit on the thermal efficiency of all heat engines. Even an ideal, frictionless engine cant convert anywhere near 100% of its heat into work. No device converting heat into energy, regardless of its construction
32.
Fuel
–
A fuel is any material that can be made to react with other substances so that it releases chemical or nuclear energy as heat or to be used for work. The concept was applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy such as nuclear energy. The heat energy released by reactions of fuels is converted into mechanical energy via a heat engine, other times the heat itself is valued for warmth, cooking, or industrial processes, as well as the illumination that comes with combustion. Fuels are also used in the cells of organisms in a known as cellular respiration. Hydrocarbons and related oxygen-containing molecules are by far the most common source of fuel used by humans, fuels are contrasted with other substances or devices storing potential energy, such as those that directly release electrical energy or mechanical energy. The first known use of fuel was the combustion of wood or sticks by Homo erectus near 2,000,000 years ago, throughout most of human history fuels derived from plants or animal fat were only used by humans. Charcoal, a derivative, has been used since at least 6,000 BCE for melting metals. It was only supplanted by coke, derived from coal, as European forests started to become depleted around the 18th century, charcoal briquettes are now commonly used as a fuel for barbecue cooking. Coal was first used as a fuel around 1000 BCE in China, coal was later used to drive ships and locomotives. By the 19th century, gas extracted from coal was being used for lighting in London. In the 20th and 21st centuries, the use of coal is to generate electricity. Fossil fuels were rapidly adopted during the revolution, because they were more concentrated and flexible than traditional energy sources. They have become a part of our contemporary society, with most countries in the world burning fossil fuels in order to produce power. Currently the trend has been towards renewable fuels, such as biofuels like alcohols, chemical fuels are substances that release energy by reacting with substances around them, most notably by the process of combustion. Most of the energy released in combustion was not stored in the chemical bonds of the fuel. Chemical fuels are divided in two ways, first, by their physical properties, as a solid, liquid or gas. Secondly, on the basis of their occurrence, primary and secondary, solid fuels include wood, charcoal, peat, coal, Hexamine fuel tablets, and pellets made from wood, corn, wheat, rye and other grains. Solid-fuel rocket technology also uses solid fuel, solid fuels have been used by humanity for many years to create fire
33.
Waste heat
–
The need for many systems to reject heat as a by-product of their operation is fundamental to the laws of thermodynamics. Waste heat has lower utility than the energy source. Sources of waste heat include all manner of activities, natural systems. Rejection of unneeded cold is also a form of waste heat, thermal energy storage, which includes technologies both for short- and long-term retention of heat or cold, can create or improve the utility of waste heat. One example is waste heat from air conditioning machinery stored in a tank to aid in night time heating. Another is seasonal thermal energy storage at a foundry in Sweden, the heat is stored in the bedrock surrounding a cluster of heat exchanger equipped boreholes, and is used for space heating in an adjacent factory as needed, even months later. Another STES application is storing winter cold underground, for air conditioning. On a biological scale, all organisms reject waste heat as part of their metabolic processes, anthropogenic waste heat is thought by some to contribute to the urban heat island effect. The biggest point sources of waste heat originate from machines and heat loss through building envelopes, the burning of transport fuels is a major contribution to waste heat. Machines converting energy contained in fuels to work or electric energy produce heat as a by-product. In the majority of applications, energy is required in multiple forms. These energy forms typically include some combination of, heating, ventilation, often, these additional forms of energy are produced by a heat engine, running on a source of high-temperature heat. A heat engine can never have perfect efficiency, according to the law of thermodynamics. This is commonly referred to as heat or secondary heat. This heat is useful for the majority of heating applications, however, it is not practical to transport heat energy over long distances. The largest proportions of total waste heat are from power stations, the largest single sources are power stations and industrial plants such as oil refineries and steelmaking plants. The electrical efficiency of power plants is defined as the ratio between the input and output energy. The images show cooling towers which allow power stations to maintain the low side of the temperature difference essential for conversion of heat differences to other forms of energy, discarded or Waste heat that is lost to the environment may instead be used to advantage
34.
Thermal energy
–
In thermodynamics, thermal energy refers to the internal energy present in a system due to its temperature. Heat is energy transferred spontaneously from a hotter to a system or body. Heat is energy in transfer, not a property of the system, on the other hand, internal energy is a property of a system. The internal energy of a gas can in this sense be regarded as thermal energy. In this case, however, thermal energy and internal energy are identical, systems that are more complex than ideal gases can undergo phase transitions. Phase transitions can change the energy of the system without changing its temperature. Therefore, the thermal energy cannot be defined solely by the temperature, for these reasons, the concept of the thermal energy of a system is ill-defined and is not used in thermodynamics. In an 1847 lecture entitled On Matter, Living Force, and Heat, James Prescott Joule characterized various terms that are related to thermal energy. He identified the terms latent heat and sensible heat as forms of heat each effecting distinct physical phenomena, namely the potential and kinetic energy of particles, Heat transfer Ocean thermal energy conversion Thermal science Example of incorrect use of heat and thermal energy
35.
HVAC
–
Heating, ventilation and air conditioning is the technology of indoor and vehicular environmental comfort. Its goal is to provide comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, Refrigeration is sometimes added to the fields abbreviation as HVAC&R or HVACR, or ventilating is dropped as in HACR. Ventilation removes unpleasant smells and excessive moisture, introduces outside air, keeps interior building air circulating, ventilation includes both the exchange of air to the outside as well as circulation of air within the building. It is one of the most important factors for maintaining acceptable indoor air quality in buildings, methods for ventilating a building may be divided into mechanical/forced and natural types. HVAC systems can be used in domestic and commercial environments. HVAC systems can provide ventilation, reduce air infiltration, and maintain pressure relationships between spaces, the means of air delivery and removal from spaces is known as room air distribution. In modern buildings the design, installation, and control systems of functions are integrated into one or more HVAC systems. For very small buildings, contractors normally estimate the capacity, engineer, for larger buildings, building service designers, mechanical engineers, or building services engineers analyze, design, and specify the HVAC systems. Specialty mechanical contractors then fabricate and commission the systems, Building permits and code-compliance inspections of the installations are normally required for all sizes of building. HVAC is based on inventions and discoveries made by Nikolay Lvov, Michael Faraday, Willis Carrier, Edwin Ruud, Reuben Trane, James Joule, William Rankine, Sadi Carnot, heaters are appliances whose purpose is to generate heat for the building. This can be done via central heating, such a system contains a boiler, furnace, or heat pump to heat water, steam, or air in a central location such as a furnace room in a home, or a mechanical room in a large building. The heat can be transferred by convection, conduction, or radiation, heaters exist for various types of fuel, including solid fuels, liquids, and gases. Another type of source is electricity, normally heating ribbons composed of high resistance wire. This principle is used for baseboard heaters and portable heaters. Electrical heaters are used as backup or supplemental heat for heat pump systems. The heat pump gained popularity in the 1950s in Japan and the United States, heat pumps can extract heat from various sources, such as environmental air, exhaust air from a building, or from the ground. In the case of heated water or steam, piping is used to transport the heat to the rooms, most modern hot water boiler heating systems have a circulator, which is a pump, to move hot water through the distribution system
36.
Distributed generation
–
By contrast, DER systems are decentralized, modular and more flexible technologies, that are located close to the load they serve, albeit having capacities of only 10 megawatts or less. These systems can comprise multiple generation and storage components, in this instance they are referred to as Hybrid power systems. A grid-connected device for electricity storage can also be classified as a DER system, by means of an interface, DER systems can be managed and coordinated within a smart grid. Distributed generation and storage enables collection of energy from many sources and may lower environmental impacts, microgrids are modern, localized, small-scale grids, contrary to the traditional, centralized electricity grid. Microgrids can disconnect from the grid and operate autonomously, strengthen grid resilience. They are typically low-voltage AC grids, often use diesel generators, microgrids increasingly employ a mixture of different distributed energy resources, such as solar hybrid power systems, which reduce the amount of emitted carbon significantly. These, in turn, supply the traditional transmission and distribution grid that distributes power to load centers. These were developed when the costs of transporting fuel and integrating generating technologies into populated areas far exceeded the cost of developing T&D facilities, central plants are usually designed to take advantage of available economies of scale in a site-specific manner, and are built as one-off, custom projects. Thus, the grid had become the driver of remote customers’ power costs and power quality problems. Efficiency gains no longer come from increasing generating capacity, but from smaller units located closer to sites of demand, for example, coal power plants are built away from cities to prevent their heavy air pollution from affecting the populace. In addition, such plants are built near collieries to minimize the cost of transporting coal. Hydroelectric plants are by their nature limited to operating at sites with sufficient water flow, low pollution is a crucial advantage of combined cycle plants that burn natural gas. The low pollution permits the plants to be enough to a city to provide district heating and cooling. Distributed energy resources are mass-produced, small, and less site-specific, smaller units offered greater economies from mass-production than big ones could gain through unit size. DG, vis-à-vis central plants, must be justified on a life-cycle basis, unfortunately, many of the direct, and virtually all of the indirect, benefits of DG are not captured within traditional utility cash-flow accounting. Distributed generation reduces the amount of energy lost in transmitting electricity because the electricity is generated very near where it is used and this also reduces the size and number of power lines that must be constructed. Typical DER systems in a feed-in tariff scheme have low maintenance, low pollution, in the past, these traits required dedicated operating engineers and large complex plants to reduce pollution. However, modern embedded systems can provide these traits with automated operation and renewables, such as sunlight, wind and this reduces the size of power plant that can show a profit
37.
Absorption refrigerator
–
An absorption refrigerator is a refrigerator that uses a heat source to provide the energy needed to drive the cooling process. Absorption refrigerators are used for food storage in recreational vehicles. The principle can also be used to air-condition buildings using the heat from a gas turbine or water heater. Using waste heat from a gas turbine makes the very efficient because it first produces electricity, then hot water. The standard for the refrigerator is given by the ANSI/AHRI standard 560-2000. Nowadays, the vapor absorption cycle is used only where waste heat is available or where heat is derived from solar collectors, Absorption cooling was invented by the French scientist Ferdinand Carré in 1858. The original design used water and sulphuric acid, in 1922 Baltzar von Platen and Carl Munters, while they were still students at the Royal Institute of Technology in Stockholm, Sweden, enhanced the principle with a 3-fluid configuration. This Platen-Munters design can operate without a pump, commercial production began in 1923 by the newly formed company AB Arctic, which was bought by Electrolux in 1925. In the 1960s, the absorption refrigeration saw a renaissance due to the demand for refrigerators for caravans. AB Electrolux established a subsidiary in the United States, named Dometic Sales Corporation, the company marketed refrigerators for RVs under the Dometic brand. In 2001, Electrolux sold most of its leisure products line to the venture-capital company EQT which created Dometic as a stand-alone company, in 1926, Albert Einstein and his former student Leó Szilárd proposed an alternative design known as the Einstein refrigerator. At the 2007 TED Conference, Adam Grosser presented his research of a new, very small, intermittent absorption vaccine refrigeration unit for use in third world countries. The refrigerator is a unit placed over a campfire, that can later be used to cool 15 liters of water to just above freezing for 24 hours in a 30 °C environment. Both absorption and compressor refrigerators use a refrigerant with a low boiling point. In both types, when this refrigerant evaporates, it takes some heat away with it, providing the cooling effect, the main difference between the two systems is the way the refrigerant is changed from a gas back into a liquid so that the cycle can repeat. An absorption refrigerator changes the gas back into a liquid using a method that needs only heat, the absorption cooling cycle can be described in three phases, Evaporation, A liquid refrigerant evaporates in a low partial pressure environment, thus extracting heat from its surroundings. Because of the low pressure, the temperature needed for evaporation is also low. Absorption, The now gaseous refrigerant is absorbed by another liquid, regeneration, The refrigerant-saturated liquid is heated, causing the refrigerant to evaporate out
38.
Gas turbine
–
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a turbine. The basic operation of the gas turbine is similar to that of the power plant except that the working fluid is air instead of water. Fresh atmospheric air flows through a compressor that brings it to higher pressure, energy is then added by spraying fuel into the air and igniting it so the combustion generates a high-temperature flow. This high-temperature high-pressure gas enters a turbine, where it expands down to the exhaust pressure, the turbine shaft work is used to drive the compressor and other devices such as an electric generator that may be coupled to the shaft. The energy that is not used for shaft work comes out in the exhaust gases, the purpose of the gas turbine determines the design so that the most desirable energy form is maximized. Gas turbines are used to power aircraft, trains, ships, electrical generators,50, Heros Engine — Apparently, Heros steam engine was taken to be no more than a toy, and thus its full potential not realized for centuries. 1000, The Trotting Horse Lamp was used by the Chinese at lantern fairs as early as the Northern Song dynasty. When the lamp is lit, the heated airflow rises and drives an impeller with horse-riding figures attached on it,1629, Jets of steam rotated an impulse turbine that then drove a working stamping mill by means of a bevel gear, developed by Giovanni Branca. 1678, Ferdinand Verbiest built a model carriage relying on a jet for power. 1791, A patent was given to John Barber, an Englishman and his invention had most of the elements present in the modern day gas turbines. The turbine was designed to power a horseless carriage,1861, British patent no.1633 was granted to Marc Antoine Francois Mennons for a Caloric engine. The patent shows that it was a gas turbine and the show it applied to a locomotive. Also named in the patent was Nicolas de Telescheff, a Russian aviation pioneer,1872, A gas turbine engine was designed by Franz Stolze, but the engine never ran under its own power. 1894, Sir Charles Parsons patented the idea of propelling a ship with a turbine, and built a demonstration vessel. This principle of propulsion is still of some use,1895, Three 4-ton 100 kW Parsons radial flow generators were installed in Cambridge Power Station, and used to power the first electric street lighting scheme in the city. 1899, Charles Gordon Curtis patented the first gas engine in the USA. 1900, Sanford Alexander Moss submitted a thesis on gas turbines, in 1903, Moss became an engineer for General Electrics Steam Turbine Department in Lynn, Massachusetts
39.
Steam turbine
–
A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Sir Charles Parsons in 1884, in 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit. Steam turbines were described by the Italian Giovanni Branca and John Wilkins in England. The devices described by Taqi al-Din and Wilkins are today known as steam jacks, in 1672 an impulse steam turbine driven car was designed by Ferdinand Verbiest. A more modern version of car was produced some time in the late 18th century by an unknown German mechanic. The modern steam turbine was invented in 1884 by Sir Charles Parsons, the invention of Parsons steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare. Parsons design was a reaction type and his patent was licensed and the turbine scaled-up shortly after by an American, George Westinghouse. The Parsons turbine also turned out to be easy to scale up. Parsons had the satisfaction of seeing his invention adopted for all major world power stations, a number of other variations of turbines have been developed that work effectively with steam. The de Laval turbine accelerated the steam to full speed before running it against a turbine blade, De Lavals impulse turbine is simpler, less expensive and does not need to be pressure-proof. It can operate with any pressure of steam, but is less efficient. He taught at the École des mines de Saint-Étienne for a decade until 1897, one of the founders of the modern theory of steam and gas turbines was Aurel Stodola, a Slovak physicist and engineer and professor at the Swiss Polytechnical Institute in Zurich. His work Die Dampfturbinen und ihre Aussichten als Wärmekraftmaschinen was published in Berlin in 1903, a further book Dampf und Gas-Turbinen was published in 1922. It was used in John Brown-engined merchant ships and warships, including liners, the present-day manufacturing industry for steam turbines is dominated by Chinese power equipment makers. Other manufacturers with minor market share include Bhel, Siemens, Alstom, GE, Doosan Škoda Power, Mitsubishi Heavy Industries, the consulting firm Frost & Sullivan projects that manufacturing of steam turbines will become more consolidated by 2020 as Chinese power manufacturers win increasing business outside of China. There are several classifications for modern steam turbines, Turbine blades are of two basic types, blades and nozzles. Blades move entirely due to the impact of steam on them and this results in a steam velocity drop and essentially no pressure drop as steam moves through the blades. A turbine composed of alternating with fixed nozzles is called an impulse turbine, Curtis turbine, Rateau turbine
40.
Gas engine
–
A gas engine is an internal combustion engine which runs on a gas fuel, such as coal gas, producer gas, biogas, landfill gas or natural gas. In the UK, the term is unambiguous, in the US, due to the widespread use of gas as an abbreviation for gasoline, such an engine might also be called a gaseous-fueled engine or natural gas engine or spark ignited. Typical power ranges from 10 kW to 4,000 kW, there were many experiments with gas engines in the 19th century but the first practical gas-fuelled internal combustion engine was built by the Belgian engineer Étienne Lenoir in 1860. However, the Lenoir engine suffered from a low power output and his work was further researched and improved by a German engineer Nikolaus August Otto, who was later to invent the first 4-stroke engine to efficiently burn fuel directly in a piston chamber. In 1867 Otto patented his design and it was awarded the Grand Prize at the 1867 Paris World Exhibition. This atmospheric engine worked by drawing a mixture of gas and air into a vertical cylinder. When the piston has risen about eight inches, the gas and air mixture is ignited by a pilot flame burning outside. No work is done on the upward stroke, the work is done when the piston and toothed rack descend under the effects of atmospheric pressure and their own weight, turning the main shaft and flywheels as they fall. Its advantage over the steam engine was its ability to be started and stopped on demand. The atmospheric gas engine was in turn replaced by Ottos four-stroke engine, the changeover to four-stroke engines was remarkably rapid, with the last atmospheric engines being made in 1877. Liquid-fuelled engines soon followed using diesel or gasoline, the best-known builder of gas engines in the UK was Crossley of Manchester, who in 1869 acquired the UK and world rights to the patents of Otto and Langden for the new gas-fuelled atmospheric engine. In 1876 they acquired the rights to the more efficient Otto four-stroke cycle engine, there were several other firms based in the Manchester area as well. Tangye Ltd. of Smethwick, near Birmingham, sold its first gas engine, a 1 nominal horsepower two-cycle type, in 1881, output ranges from about 10 kW micro CHP to 18 MW. Rolls-Royce with the Bergen Engines, Caterpillar and many other manufacturers base their products on an engine block. GE Jenbacher and Waukesha are the two companies whose engines are designed and dedicated to gas alone. Typical applications are baseload or high-hour generation schemes, including combined heat and power (for typical performance figures see, landfill gas, mines gas, for typical biogas engine installation parameters see. For parameters of a gas engine CHP system, as fitted in a factory. Gas engines are used for standby applications, which remain largely the province of diesel engines
41.
Diesel engine
–
Diesel engines work by compressing only the air. This increases the air temperature inside the cylinder to such a degree that it ignites atomised diesel fuel that is injected into the combustion chamber. This contrasts with spark-ignition engines such as an engine or gas engine. In diesel engines, glow plugs may be used to aid starting in cold weather, or when the engine uses a lower compression-ratio, the original diesel engine operates on the constant pressure cycle of gradual combustion and produces no audible knock. Low-speed diesel engines can have an efficiency that exceeds 50%. Diesel engines may be designed as either two-stroke or four-stroke cycles and they were originally used as a more efficient replacement for stationary steam engines. Since the 1910s they have used in submarines and ships. Use in locomotives, trucks, heavy equipment and electricity generation plants followed later, in the 1930s, they slowly began to be used in a few automobiles. Since the 1970s, the use of engines in larger on-road and off-road vehicles in the US increased. According to the British Society of Motor Manufacturing and Traders, the EU average for diesel cars accounts for 50% of the total sold, including 70% in France and 38% in the UK. The worlds largest diesel engine is currently a Wärtsilä-Sulzer RTA96-C Common Rail marine diesel, the definition of a Diesel engine to many has become an engine that uses compression ignition. To some it may be an engine that uses heavy fuel oil, to others an engine that does not use spark ignition. However the original cycle proposed by Rudolf Diesel in 1892 was a constant temperature cycle which would require higher compression than what is needed for compression ignition. Diesels idea was to compress the air so tightly that the temperature of the air would exceed that of combustion, to make this more clear, let it be assumed that the subsequent combustion shall take place at a temperature of 700°. Then in that case the pressure must be sixty-four atmospheres, or for 800° centigrade the pressure must be ninety atmospheres. In later years Diesel realized his original cycle would not work, Diesel describes the cycle in his 1895 patent application. Notice that there is no longer a mention of compression temperatures exceeding the temperature of combustion, now all that is mentioned is the compression must be high enough for ignition. In 1806 Claude and Nicéphore Niépce developed the first known internal combustion engine, the Pyréolophore fuel system used a blast of air provided by a bellows to atomize Lycopodium
42.
Denmark
–
The term Danish Realm refers to the relationship between Denmark proper, the Faroe Islands and Greenland—three countries constituting the Kingdom of Denmark. The legal nature of the Kingdom of Denmark is fundamentally one of a sovereign state. The Faroe Islands and Greenland have been part of the Crown of Denmark since 1397 when the Kalmar Union was ratified, legal matters in The Danish Realm are subject to the Danish Constitution. Beginning in 1953, state law issues within The Danish Realm has been governed by The Unity of the Realm, a less formal name for The Unity of the Realm is the Commonwealth of the Realm. In 1978, The Unity of The Realm was for the first time referred to as rigsfællesskabet. The name caught on and since the 1990s, both The Unity of The Realm and The Danish Realm itself has increasingly been referred to as simply rigsfællesskabet in daily parlance. The Danish Constitution stipulates that the foreign and security interests for all parts of the Danish Realm are the responsibility of the Danish government, the Faroes received home rule in 1948 and Greenland did so in 1979. In 2005, the Faroes received a self-government arrangement, and in 2009 Greenland received self rule, the Danish Realms unique state of internal affairs is acted out in the principle of The Unity of the Realm. This principle is derived from Article 1 of the Danish Constitution which specifies that constitutional law applies equally to all areas of the Danish Realm, the Constitutional Act specifies that sovereignty is to continue to be exclusively with the authorities of the Realm. The language of Denmark is Danish, and the Danish state authorities are based in Denmark, the Kingdom of Denmarks parliament, with its 179 members, is located in the capital, Copenhagen. Two of the members are elected in each of Greenland and the Faroe Islands. The Government ministries are located in Copenhagen, as is the highest court, in principle, the Danish Realm constitutes a unified sovereign state, with equal status between its constituent parts. Devolution differs from federalism in that the powers of the subnational authority ultimately reside in central government. The Self-Government Arrangements devolves political competence and responsibility from the Danish political authorities to the Faroese, the Faroese and Greenlandic authorities administer the tasks taken over from the state, enact legislation in these specific fields and have the economic responsibility for solving these tasks. The Danish government provides a grant to the Faroese and the Greenlandic authorities to cover the costs of these devolved areas. The 1948 Home Rule Act of the Faroe Islands sets out the terms of Faroese home rule, the Act states. the Faroe Islands shall constitute a self-governing community within the State of Denmark. It establishes the government of the Faroe Islands and the Faroese parliament. The Faroe Islands were previously administered as a Danish county, the Home Rule Act abolished the post of Amtmand and these powers were expanded in a 2005 Act, which named the Faroese home government as an equal partner with the Danish government
43.
District heating
–
District heating is a system for distributing heat generated in a centralized location for residential and commercial heating requirements such as space heating and water heating. District heating plants can provide higher efficiencies and better control than localized boilers. A combination of CHP and centralized heat pumps are used in the Stockholm multi energy system, the core element of many district heating systems is a heat-only boiler station. Additionally a cogeneration plant is added in parallel with the boilers. Both have in common that they are based on combustion of primary energy carriers. In the case of a fossil fueled cogeneration plant, the output is typically sized to meet half of the peak heat load. The boiler capacity will be able to meet the entire heat demand unaided and it is not economic to size the cogeneration plant alone to be able to meet the full heat load. In the New York City steam system, that is around 2.5 GW, Germany has the largest amount of CHP in Europe. The combination of cogeneration and district heating is very energy efficient, a simple thermal power station can be 20–35% efficient, whereas a more advanced facility with the ability to recover waste heat can reach total energy efficiency of nearly 80%. Some may exceed 100% based on the heating value by condensing the flue gas as well. Waste heat from nuclear plants is sometimes used for district heating. The principles for a combination of cogeneration and district heating applies the same for nuclear as it does for a thermal power station. Russia has several cogeneration nuclear plants which together provided 11.4 PJ of district heat in 2005, Russian nuclear district heating is planned to nearly triple within a decade as new plants are built. Other nuclear-powered heating from cogeneration plants are in Ukraine, the Czech Republic, Slovakia, Hungary, Bulgaria, one use of nuclear heat generation was with the Ågesta Nuclear Power Plant in Sweden closed in 1974. In Switzerland, the Beznau Nuclear Power Plant provides heat to about 20,000 people, history Geothermal district heating was used in Pompeii, and in Chaudes-Aigues since the 14th Century. In 1890, the first wells were drilled to access a hot water resource outside of Boise, in 1892, after routing the water to homes and businesses in the area via a wooden pipeline, the first geothermal district heating system was created. As of a 2007 study, there were 22 geothermal district heating systems in the United States, as of 2010, two of those systems have shut down. The table below describes the 20 GDHS currently operational in America, use of solar heat for district heating has been increasing in Denmark and Germany in recent years
44.
Thermal power station
–
A thermal power station is a power plant in which heat energy is converted to electric power. In most of the places in the world the turbine is steam-driven, water is heated, turns into steam and spins a steam turbine which drives an electrical generator. After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was heated, this is known as a Rankine cycle. The greatest variation in the design of power stations is due to the different heat sources, fossil fuel dominates here, although nuclear heat energy. Some prefer to use the energy center because such facilities convert forms of heat energy into electrical energy. Certain thermal power plants also are designed to heat energy for industrial purposes of district heating, or desalination of water. Almost all coal, nuclear, geothermal, solar thermal electric, natural gas is frequently combusted in gas turbines as well as boilers. Power plants burning coal, fuel oil, or natural gas are often called fossil-fuel power plants, some biomass-fueled thermal power plants have appeared also. Non-nuclear thermal power plants, particularly fossil-fueled plants, which do not use co-generation are sometimes referred to as power plants. Commercial electric utility power stations are constructed on a large scale. Virtually all Electric power plants use three-phase electrical generators to produce alternating current electric power at a frequency of 50 Hz or 60 Hz. Large companies or institutions may have their own power plants to supply heating or electricity to their facilities, steam-driven power plants have been used to drive most ships in most of the 20th century until recently. Steam power plants are now used in large nuclear naval ships. Shipboard power plants usually directly couple the turbine to the propellers through gearboxes. Power plants in such ships also provide steam to turbines driving electric generators to supply electricity. Nuclear marine propulsion is, with few exceptions, used only in naval vessels, there have been many turbo-electric ships in which a steam-driven turbine drives an electric generator which powers an electric motor for propulsion. Combined heat and power plants, often called co-generation plants, produce both electric power and heat for heat or space heating. The initially developed reciprocating steam engine has been used to produce mechanical power since the 18th Century, the development of the steam turbine in 1884 provided larger and more efficient machine designs for central generating stations
45.
Paper mill
–
A paper mill is a factory devoted to making paper from vegetable fibres such as wood pulp, old rags and other ingredients. While the use of human and animal powered mills was known to Chinese and Muslim papermakers, the general absence of the use of water-power in Muslim papermaking is suggested by the habit of Muslim authors to call a production center not a mill, but a paper manufactory. Although scholars have identified paper mills in Abbasid-era Baghdad in 794–795, in the Moroccan city of Fez, Ibn Battuta speaks of 400 mill stones for paper. Since Ibn Battuta does not mention the use of water-power and such a number of water-mills would be grotesquely high, the passage is generally taken to refer to human or animal force. An exhaustive survey of milling in Al-Andalus did not uncover a single water-powered paper mill, Burns remains altogether sceptical given the isolated occurrence of the reference and the prevalence of manual labour in Islamic papermaking elsewhere. Likewise, the identification of early hydraulic stamping mills in medieval documents from Fabriano, the earliest certain evidence to a water-powered paper mill dates to 1282 in the Spanish Kingdom of Aragon. A decree by the Christian king Peter III addresses the establishment of a royal molendinum, the first permanent paper mill north of the Alps was established in Nuremberg by Ulman Stromer in 1390, it is later depicted in the lavishly illustrated Nuremberg Chronicle. From the mid-14th century onwards, European paper milling underwent an improvement of many work processes. The size of a paper mill prior to the use of machines was described by counting the number of vats it had. Thus, a one vat paper mill had only one vatman, one coucher, by the early 20th century, paper mills sprang up around New England and the rest of the world, due to the high demand for paper. At this time, there were many leaders of the production of paper, one of such was the Brown Company in Berlin. During the year 1907, the Brown Company cut between 30 and 40 million acres of woodlands on their property, which extended from La Tuque, Quebec, Canada to West Palm, “Log drives” were conducted on local rivers to send the logs to the mills. By the late 20th and early 21st-century, paper began to close. Due to the addition of new machinery, many millworkers were laid off, Paper mills can be fully integrated mills or nonintegrated mills. Integrated mills consist of a mill and a paper mill on the same site. Such mills receive logs or wood chips and produce paper, modern paper machines can be 500 feet in length, produce a sheet 400 inches wide, and operate at speeds of more than 60 miles per hour. The two main suppliers of paper machines are Metso and Voith, Paper pollution Cutting stock problem List of paper mills Burns, Robert I. Paper comes to the West, 800−1400, in Lindgren, Uta, mann Verlag, pp. biz - Paper world directory and search engine for the pulp and paper world List of paper mills on paper and print monthly
46.
Enthalpy
–
Enthalpy /ˈɛnθəlpi/ is a measurement of energy in a thermodynamic system. It is the thermodynamic quantity equivalent to the heat content of a system. It is equal to the energy of the system plus the product of pressure. Enthalpy is defined as a function that depends only on the prevailing equilibrium state identified by the systems internal energy, pressure. The unit of measurement for enthalpy in the International System of Units is the joule, but other historical, conventional units are still in use, such as the British thermal unit and the calorie. At constant pressure, the enthalpy change equals the energy transferred from the environment through heating or work other than expansion work, the total enthalpy, H, of a system cannot be measured directly. The same situation exists in classical mechanics, only a change or difference in energy carries physical meaning. Enthalpy itself is a potential, so in order to measure the enthalpy of a system, we must refer to a defined reference point, therefore what we measure is the change in enthalpy. The ΔH is a change in endothermic reactions, and negative in heat-releasing exothermic processes. For processes under constant pressure, ΔH is equal to the change in the energy of the system. This means that the change in enthalpy under such conditions is the heat absorbed by the material through a reaction or by external heat transfer. Enthalpies for chemical substances at constant pressure assume standard state, most commonly 1 bar pressure, standard state does not, strictly speaking, specify a temperature, but expressions for enthalpy generally reference the standard heat of formation at 25 °C. Enthalpy of ideal gases and incompressible solids and liquids does not depend on pressure, unlike entropy, real materials at common temperatures and pressures usually closely approximate this behavior, which greatly simplifies enthalpy calculation and use in practical designs and analyses. The word enthalpy stems from the Ancient Greek verb enthalpein, which means to warm in and it combines the Classical Greek prefix ἐν- en-, meaning to put into, and the verb θάλπειν thalpein, meaning to heat. The word enthalpy is often attributed to Benoît Paul Émile Clapeyron. This misconception was popularized by the 1927 publication of The Mollier Steam Tables, however, neither the concept, the word, nor the symbol for enthalpy existed until well after Clapeyrons death. The earliest writings to contain the concept of enthalpy did not appear until 1875, however, Gibbs did not use the word enthalpy in his writings. The actual word first appears in the literature in a 1909 publication by J. P. Dalton
47.
Metz
–
Metz is a city in northeast France located at the confluence of the Moselle and the Seille rivers. Metz is the prefecture of the Moselle department and the seat of the parliament of the Great East region, located near the tripoint along the junction of France, Germany, and Luxembourg, the city forms a central place of the European Greater Region and the SaarLorLux euroregion. The city has been steeped in Romance culture, but has strongly influenced by Germanic culture due to its location. Because of its historical, cultural, and architectural background, Metz has been submitted on Frances UNESCO World Heritage Tentative List, Metz is home to some world-class venues including the Arsenal Concert Hall and the Centre Pompidou-Metz museum. A basin of urban ecology, Metz gained its nickname of The Green City, as it has extensive open grounds, the historic city centre is one of the largest commercial pedestrian areas in France. A historic garrison town, Metz is the heart of the Lorraine region, specialising in information technology. In ancient times, the town was known as city of Mediomatrici, after its integration into the Roman Empire, the city was called Divodurum Mediomatricum, meaning Holy Village or Holy Fortress of the Mediomatrici, then it was known as Mediomatrix. During the 5th century AD, the name evolved to Mettis, Metz has a recorded history dating back over 3,000 years. Before the conquest of Gaul by Julius Caesar in 52 BC, between the 6th and 8th centuries, the city was the residence of the Merovingian kings of Austrasia. After the Treaty of Verdun in 843, Metz became the capital of the Kingdom of Lotharingia and was integrated into the Holy Roman Empire. During the 12th century, Metz rose to the status of Republic, with the signature of the Treaty of Chambord in 1552, Metz passed to the hands of the Kings of France. Under French rule, Metz was selected as capital of the Three Bishoprics, with creation of the departments by the Estates-General of 1789, Metz was chosen as capital of the Department of Moselle. Metz remained German until the end of World War I, when it reverted to France, however, after the Battle of France during the Second World War, the city was annexed once more by the German Third Reich. In 1944, the attack on the city by the U. S, Third Army freed the city from German rule and Metz reverted one more time to France after World War II. During the 1950s, Metz was chosen to be the capital of the newly created Lorraine region, with the creation of the European Community and the later European Union, the city has become central to the Greater Region and the SaarLorLux Euroregion. Metz is located on the banks of the Moselle and the Seille rivers,43 km from the Schengen tripoint where the borders of France, Germany, and Luxembourg meet. The city was built in a place where branches of the Moselle river creates several islands. The terrain of Metz forms part of the Paris Basin and presents a plateau relief cut by river valleys presenting cuestas in the north-south direction
48.
France
–
France, officially the French Republic, is a country with territory in western Europe and several overseas regions and territories. The European, or metropolitan, area of France extends from the Mediterranean Sea to the English Channel and the North Sea, Overseas France include French Guiana on the South American continent and several island territories in the Atlantic, Pacific and Indian oceans. France spans 643,801 square kilometres and had a population of almost 67 million people as of January 2017. It is a unitary republic with the capital in Paris. Other major urban centres include Marseille, Lyon, Lille, Nice, Toulouse, during the Iron Age, what is now metropolitan France was inhabited by the Gauls, a Celtic people. The area was annexed in 51 BC by Rome, which held Gaul until 486, France emerged as a major European power in the Late Middle Ages, with its victory in the Hundred Years War strengthening state-building and political centralisation. During the Renaissance, French culture flourished and a colonial empire was established. The 16th century was dominated by civil wars between Catholics and Protestants. France became Europes dominant cultural, political, and military power under Louis XIV, in the 19th century Napoleon took power and established the First French Empire, whose subsequent Napoleonic Wars shaped the course of continental Europe. Following the collapse of the Empire, France endured a succession of governments culminating with the establishment of the French Third Republic in 1870. Following liberation in 1944, a Fourth Republic was established and later dissolved in the course of the Algerian War, the Fifth Republic, led by Charles de Gaulle, was formed in 1958 and remains to this day. Algeria and nearly all the colonies became independent in the 1960s with minimal controversy and typically retained close economic. France has long been a centre of art, science. It hosts Europes fourth-largest number of cultural UNESCO World Heritage Sites and receives around 83 million foreign tourists annually, France is a developed country with the worlds sixth-largest economy by nominal GDP and ninth-largest by purchasing power parity. In terms of household wealth, it ranks fourth in the world. France performs well in international rankings of education, health care, life expectancy, France remains a great power in the world, being one of the five permanent members of the United Nations Security Council with the power to veto and an official nuclear-weapon state. It is a member state of the European Union and the Eurozone. It is also a member of the Group of 7, North Atlantic Treaty Organization, Organisation for Economic Co-operation and Development, the World Trade Organization, originally applied to the whole Frankish Empire, the name France comes from the Latin Francia, or country of the Franks
