Solar power is the conversion of energy from sunlight into electricity, either directly using photovoltaics, indirectly using concentrated solar power, or a combination. Concentrated solar power systems use lenses or mirrors and solar tracking systems to focus a large area of sunlight into a small beam. Photovoltaic cells convert light into an electric current using the photovoltaic effect. Photovoltaics were solely used as a source of electricity for small and medium-sized applications, from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system. Commercial concentrated solar power plants were first developed in the 1980s; as the cost of solar electricity has fallen, the number of grid-connected solar PV systems has grown into the millions and utility-scale photovoltaic power stations with hundreds of megawatts are being built. Solar PV is becoming an inexpensive, low-carbon technology to harness renewable energy from the Sun; the current largest photovoltaic power station in the world is the Pavagada Solar Park, India with a generation capacity of 2050 MW.
The International Energy Agency projected in 2014 that under its "high renewables" scenario, by 2050, solar photovoltaics and concentrated solar power would contribute about 16 and 11 percent of the worldwide electricity consumption, solar would be the world's largest source of electricity. Most solar installations would be in India. In 2017, solar power provided 1.7% of total worldwide electricity production, growing 35% from the previous year. As of 2018, the unsubsidised levelised cost of electricity for utility-scale solar power is around $43/MWh. Many industrialized nations have installed significant solar power capacity into their grids to supplement or provide an alternative to conventional energy sources while an increasing number of less developed nations have turned to solar to reduce dependence on expensive imported fuels. Long distance transmission allows remote renewable energy resources to displace fossil fuel consumption. Solar power plants use one of two technologies: Photovoltaic systems use solar panels, either on rooftops or in ground-mounted solar farms, converting sunlight directly into electric power.
Concentrated solar power plants use solar thermal energy to make steam, thereafter converted into electricity by a turbine. A solar cell, or photovoltaic cell, is a device that converts light into electric current using the photovoltaic effect; the first solar cell was constructed by Charles Fritts in the 1880s. The German industrialist Ernst Werner von Siemens was among those who recognized the importance of this discovery. In 1931, the German engineer Bruno Lange developed a photo cell using silver selenide in place of copper oxide, although the prototype selenium cells converted less than 1% of incident light into electricity. Following the work of Russell Ohl in the 1940s, researchers Gerald Pearson, Calvin Fuller and Daryl Chapin created the silicon solar cell in 1954; these early solar cells cost US$286/watt and reached efficiencies of 4.5–6%. In 1957, Mohamed M. Atalla developed the process of silicon surface passivation by thermal oxidation at Bell Labs; the surface passivation process has since been critical to solar cell efficiency.
The array of a photovoltaic power system, or PV system, produces direct current power which fluctuates with the sunlight's intensity. For practical use this requires conversion to certain desired voltages or alternating current, through the use of inverters. Multiple solar cells are connected inside modules. Modules are wired together to form arrays tied to an inverter, which produces power at the desired voltage, for AC, the desired frequency/phase. Many residential PV systems are connected to the grid wherever available in developed countries with large markets. In these grid-connected PV systems, use of energy storage is optional. In certain applications such as satellites, lighthouses, or in developing countries, batteries or additional power generators are added as back-ups; such stand-alone power systems permit operations at other times of limited sunlight. Concentrated solar power called "concentrated solar thermal", uses lenses or mirrors and tracking systems to concentrate sunlight use the resulting heat to generate electricity from conventional steam-driven turbines.
A wide range of concentrating technologies exists: among the best known are the parabolic trough, the compact linear Fresnel reflector, the dish Stirling and the solar power tower. Various techniques are used to track the focus light. In all of these systems a working fluid is heated by the concentrated sunlight, is used for power generation or energy storage. Thermal storage efficiently allows up to 24-hour electricity generation. A parabolic trough consists of a linear parabolic reflector that concentrates light onto a receiver positioned along the reflector's focal line; the receiver is a tube positioned along the focal points of the linear parabolic mirror and is filled with a working fluid. The reflector is made to follow the sun during daylight hours by tracking along a single axis. Parabolic trough systems provide the best land-use factor of any solar technology; the Solar Energy Generating Systems plants in California and Acciona's Nevada Solar One near Boulder City, Nevada are representatives of this technology.
Compact Linear Fresnel Reflectors are CSP-plants which use many thin mirror strips instead of parabolic mirrors to concentrate sunlight onto two tubes with working fluid. This has the advantage that flat mirrors can be used which are much cheaper than parabolic mirrors, that more reflecto
Jackson Nickerson is an American academic who studies leadership and strategy. Nickerson is the Frahm Family Professor of Organization and Strategy in Olin Business School at Washington University in St. Louis, he was the associate Dean and Director of Brookings Executive Education from 2009-2017 and is a non-resident Senior Fellow in Governance Studies at the Brookings Institution. Nickerson grew up in Weymouth, attended Worcester Polytechnic Institute where he received a Bachelor of Science in Mechanical Engineering, followed by a Masters in Mechanical Engineering at University of California, Berkeley, he worked for NASA’s Jet Propulsion Laboratory, before returning to Berkeley for a Master in Business Administration from the Haas School of Business. He returned to Haas for a Ph. D. working for six years as a consultant for the Law and Economics Consulting Group. Nickerson was appointed assistant professor at Olin Business School in 1996, promoted to associate professor, full professor, the Frahm Family Professor of Organization and Strategy.
After becoming strategy group chair in 2008, he was appointed Director of Brookings Executive Education in 2009 and became its associate dean in 2010. In 2009 he became a non-resident Senior Fellow in Governance Studies at the Brookings Institution and was the first Senior Visiting Fellow at the Grameen Foundation in 2010 and 2011. From 2013 through 2014 he wrote the leadership columns “Ask EIG: Leadership insights for Federal managers” for Government Executive Online and has been a speaker for the Institute of Management Studies since 2014. Nickerson’s early research built upon Oliver Williamson’s transaction cost economics to predict the antecedents and performance consequences of organizational choices in a wide variety of empirical settings and industries. Along with Todd Zenger, he introduced the concepts of organizational vacillation and envy as foundations to firm boundaries, is credited with introducing the Problem Finding and Problem Solving Perspective, which provides a knowledge-based foundation for a theory of firm boundaries, organizational choice and the design of group processes to overcome biases.
In 1995, Nickerson co-founded the Intellectual Capital Management Group. In 2006, he co-founded NFORMD. NET, a new media company that through its subsidiary StudentSuccess.org provides sexual assault prevention training at over 350 colleges and universities and to the US Army. Between 2009 and 2012, he was a board member of Clean Tech Bio-fuels. Nickerson is a co-creator of Critical Thinking@Olin, an approach to teaching critical thinking that won the inaugural MBA Roundtable Innovator Award]; the approach is taught to other business schools a part of AACSB’s Curriculum Development Series. In conjunction with AACSB, he developed Leading in the Academic Enterprise, an approach for developing leaders in academia. Through Brookings Executive Education he developed and launched Leading Thinking an approach to leadership in which inquiry and critical thinking are the core. Leading in Government: Practical advice to leadership questions from the front lines'. ASIN 0692752935 J. A. Nickerson, Brookings Executive Education, 2016.
Leading Change from the Middle: A Practical Guide to Building Extraordinary Capabilities'. ASIN B00II90HX0 J. A. Nickerson, Brookings Press, 2014. Tackling Wicked Government Problems: A Practical Guide for Enterprise Leaders. J. A. Nickerson and R. Sanders, Brookings Press, 2013. ASIN 0815726392 Jackson Nickerson. Leading Change in a Web 2.1 World: How ChangeCasting Builds Trust, Creates Understanding, Accelerates Organizational Change. Brookings Institution Press. ISBN 978-0-8157-2542-8. Economic Institutions of Strategy. J. A. Nickerson and B. S. Silverman, Advances in Strategic Management, Emerald Group Publishing Limited, 2009. ASIN 1848554869 Nickerson Faculty Page at Olin Business School. WUSTL media Jackson Nickerson at Government Executive. Jackson Nickerson at IMS "Leading Thinking". You Tube
Drug prohibition law is prohibition-based law by which governments prohibit, except under licence, the production and possession of many, but not all, substances which are recognized as drugs, which corresponds to international treaty commitments in the Single Convention on Narcotic Drugs 1961, the Convention on Psychotropic Substances 1971, the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances 1988. When produced, supplied or possessed under licence, otherwise prohibited drugs are known as controlled drugs; the aforementioned legislation is the cultural institution and social fact that de facto divides world drug trade as illegal vs legal, according to geopolitical issues. The United Nations has its own drug control programme, as part of the United Nations Office on Drugs and Crime, called the United Nations Office for Drug Control and Crime Prevention, the Commission on Narcotic Drugs is the central drug policy-making body within the United Nations system.
The International Narcotics Control Board is an independent and quasi-judicial control organ for the implementation of the United Nations drug control conventions. It is important to note that there are several different sets of "schedules", or lists, of controlled drugs. One is the INCB schedules, while another is the United States' Controlled Substances Act schedules of controlled substances. Other countries have different classifications and numbers of lists, such as those of the United Kingdom and Canada. Drug prohibition law is based on the view that some drugs, notably opium poppy and substances derived from these plants, are so addictive or dependence inducing and so dangerous, in terms of potential effects on the health and behaviour of users, that they should be if used. Psychotropic substances covered by drug control law include psilocybin mushrooms and lysergic acid diethylamide; the following treaties are no longer in force, being superseded in 1961 by the Single Convention on Narcotic Drugs: International Opium Convention, signed at The Hague on 23 January 1912 Agreement concerning the Manufacture of, Internal Trade in and Use of Prepared Opium, signed at Geneva on 11 February 1925 Convention for Limiting the Manufacture and Regulating the Distribution of Narcotic Drugs, signed at Geneva on 13 July 1931 Agreement for the Control of Opium Smoking in the Far East, signed at Bangkok on 27 November 1931 Otherwise prohibited drugs may be licensed for medical and industrial purposes.
Pharmaceutical companies known as drug companies, work under drug control licenses. Hemp production from the Cannabis plant is an example of an industrial purpose. Recreational use and self-medicational use are not licensed under drug prohibition laws, although other drugs, not covered by such laws, may be available for this purpose. Alcohol and tobacco are notable examples of available recreational drugs. Aspirin is an example of a drug available for self-medicational purposes. Health and behavior issues, legal issues, are associated with alcohol and tobacco use, but these are not addressed through drug prohibition laws. Addiction to a prohibited drug may not be considered a legitimate reason for using it if the drug is obtained from a licensed source, or a substitute may be provided, for example, methadone instead of heroin. However, those addicted to prohibited drugs are expected to find other ways of coping with their addictions, or to risk suffering the law enforcement penalties associated with illegal possession.
There is an extensive illegal trans-national industry supplying prohibited drugs for recreational use. Thus, while drug prohibition laws remain in force, there is perpetual law enforcement action directed against the illegal industry, which impacts supply for self-medication. Although it is directed against illegal recreational drugs, not against drugs licensed under prohibition laws or against drugs beyond the scope of prohibition laws, the law enforcement is sometimes called the war on drugs. Drug prohibition is responsible for enriching "organised criminal networks", according to some critics while the hypothesis that the prohibition of drugs generates violence is consistent with research done over long time-series and cross-country facts. In the United Kingdom, where the principal piece of drug prohibition legislation is the Misuse of Drugs Act 1971, criticism includes: Drug classification: making a hash of it?, Fifth Report of Session 2005–06, House of Commons Science and Technology Committee, which said that the present system of drug classification is based on historical assumptions, not scientific assessment Development of a rational scale to assess the harm of drugs of potential misuse, David Nutt, Leslie A. King, William Saulsbury, Colin Blakemore, The Lancet, 24 March 2007, said the act is "not fit for purpose" and "the exclusion of alcohol and tobacco from the Misuse of Drugs Act is, from a scientific perspective, arbitrary" The Drug Equality Alliance argue that the Government is administering the Act arbitrarily, contrary to its purpose, contrary to the original wishes of Parliament and therefore illegally.
They are assisting and supporting several legal challenges to this alleged maladministration. Australia: Standard for the Uniform Scheduling of Drugs and Poisons Belize: Misuse of Drugs Act Canada: Controlled Drugs and Substances Act Estonia: Narcotic Drugs and Psychotropic Substances Act Germany: Betäubungsmittelgesetz India: Narcotic Drugs and Psychotropic Substances Act Netherlands: Opium Law New Zealand: Misuse of Drugs Act 1975 Pakistan: Control of Narcotic Substances Act 1997 Philippi