Solar electricity | Wikipedia audio article
Solar. Power, is the conversion of, energy from, sunlight into. Electricity either. Directly. Using, photovoltaics. Pv. Indirectly. Using, concentrated, solar. Power or a combination. Concentrated. Solar, power systems. Use, lenses or. Mirrors and. 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. Initially, 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. The. 392. Mega watt XIV ampere installation. Is the largest. Concentrating. Solar, power plant. In the world located, in, the Mojave, Desert of California. 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 of, being built. Solar. PV. Is rapidly, becoming an inexpensive. Low-carbon. Technology. To harness renewable. Energy, from the Sun the. Current, largest, photovoltaic, power. Station. In the world is, the, 850. Megawatts, long yangzhou dam solar, Park in Ching, hai China. 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 a, percent, respectively. Of the worldwide. Electricity. Consumption, and solar, would be the world's, largest source. Of electricity. Most. Solar, installations. Would be in China, and India in. 2017. Solar, power provided. 1.7. Percent of, total worldwide. Electricity. Production, growing. At 35, percent per, annum as. Of. 2018. The unsubsidized. Levelized. Cost, of electricity for. Utility-scale, solar power. Is around. $43. Per megawatt, our. Topic. Mainstream. Technologies. Many. Industrialized. Nations. Have, installed, significant. Solar power, capacity. Into the 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. See, solar, power by country. Long-distance, transmission, allows. Remote, renewable. Energy, resources, to displace, fossil, fuel consumption. Solar. Power plants. Use one of two technologies. Photovoltaic. PV. Systems. Use solar, panels either, on rooftops, or in ground mounted, solar farms, converting. Sunlight directly, into. Electric, power. Concentrated. Solar power, CSP. Also. Known as, concentrated. Solar, thermal. Farms, use solar, thermal, energy to, make steam, that is thereafter. Converted. Into electricity. By, turbine. Topic. Photovoltaics. A. Solar. Cell, or photovoltaic. Cell. PV, 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 photocell. 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 ole in the 1940s. Researchers. Gerald. Pearson Calvin. Fuller and Darrell Chapman, created, the silicon, solar cell, in, 1954. These. Early, solar cells, cost. 286. United. States dollars, per watt and reached efficiencies. Of 4.5. To 6 percent the, array of a photovoltaic, power. System. Or PV. System. Produces. Direct, current, DC power. Which fluctuates with.
The Sunlights intensity. For. Practical, use this, usually, requires, conversion. To certain, desired, voltages. Or alternating. Current. AC, through, the use of inverters. Multiple. Solar cells, are connected inside. Modules. Modules. Are wired together, to, form a raised then, tied to an inverter which produces. Power at the desired, voltage and, for AC the. Desired, frequency, phase. Many, residential. PV, systems. Are connected to the grid wherever, available. Especially 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 often added as backups. Such. Standalone, power systems. Permit, operations. At night and at other times of, limited sunlight. Topic. Concentrated. Solar power. Concentrated. Solar power. CSP. Also. Called. Concentrated. Solar, thermal. Uses. Lenses, or mirrors and. Tracking, systems to concentrate. Sunlight then, use the resulting, heat to generate electricity. From. Conventional. Steam driven turbines. A. Wide. Range of concentrating. Technologies. Exists. Among, the best-known, of the parabolic, trough, the compact, linear Fresnel, reflector. The, Stirling, dish and the solar power, tower. Various. Techniques, are used to track the Sun and focus, light in. All of these systems, are working fluid, is heated by the concentrated. Sunlight and is then 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 reflectors. 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. Segs. Plants. In California and. A key understand, Avada 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, and the more reflectors. Can be placed in the same amount of space, allowing. More of the available sunlight. To, be used. Concentrating. Linear, Fresnel, reflectors. Can be used in either large, or, more compact, pants the Stirling, solar dish combines, a parabolic. Concentrating. Dish with a Stirling, engine which, normally, drives an electric generator. The. Advantages. Of Stirling. Solar /, photovoltaic, cells. Are, higher efficiency. Of converting, sunlight into electricity, and. Longer. Lifetime. Parabolic. Dish systems. Give, the highest efficiency. Among, CSP. Technologies. The. 50, kilowatts, big, dish in Canberra, Australia. Is an example, of this technology. A solar, power, tower, uses. An array of tracking, reflectors. Heliostats. To concentrate, light on a central, receiver, atop, a tower.
Power. Towers. Can achieve higher thermal, to electricity. Conversion. Efficiency. Than linear tracking, CSP. Schemes, and better energy, storage, capability. Than dish Stirling technologies. The. PS 10, solar, power, plant, and PS 20, solar power, plant, are examples. Of this technology. Topic. Hybrid. Systems. A hybrid. System, combines. CPV. And CSP, with, one another or with other forms, of generations. Such as diesel wind, and biogas. The. Combined, form, of generation. May enable the system to, modulate, power output, as a function, of demand, or at least reduce, the fluctuating. Nature, of solar power, and the consumption. Of non-renewable, fuel. Hybrid. Systems, are most often found on, Islands. See. PV, CSP. System, a. Novel. Solar CPV. CSP. Hybrid, system, has been proposed. Combining. Concentrator. Photovoltaics. With. The non PV, technology. Of concentrated. Solar power or also known as concentrated. Solar thermal. Iscc, system. The. Hasse Armel power station. In Algeria, is an example, of combining. CSP. With a gas turbine. Where a 25. Megawatt. CSP. Parabolic. Trough array supplements. Are much larger. 130. Megawatts. Combined. Cycle gas turbine. Plant. Another. Example. Is the yazd power, station. In Iran. Pvt. System. Hybrid. PV, T also. Known as photovoltaic. Thermal. Hybrid, solar collectors. Converts, solar, radiation. Into thermal, and electrical, energy. Such. A system. Combines, a solar PV, module. With a solar, thermal collector. In a complementary. Way. See. PV, T system, a. Concentrated. Photovoltaics. Thermal. Hybrid, see PV, T system. Is similar, to a PV, T system. It. Uses. Concentrated. Photovoltaics. CPV. Instead. Of conventional. PV, technology. And combines. It with a solar, thermal collector. PV. Diesel, system. It. Combines, a photovoltaic, system. With, a diesel, generator. Combinations. With other renewables. Are possible, and include wind turbines. PV. Thermoelectric. System. Thermoelectric. Or thermo. Voltaic. Devices. Convert, a temperature, difference. Between dissimilar. Materials. Into, an electric, current. Solar. Cells, use, only the high-frequency part, of the radiation, while, the low-frequency, heat. Energy is, wasted. Several. Patents, about the use of thermoelectric. Devices in, tandem, with solar, cells, have, been filed the idea, is to increase the, efficiency, of the combined, solar, thermal, electric. System, to convert the solar radiation, into. Useful, electricity. Topic. Development, and. Deployment. You. Topic. Early. Days. The, early, development. Of solar technologies. Starting in, the 1860s. Was, driven by, an expectation, that. Coal would soon become scarce. Charles. Fritts installed. The world's, first rooftop. Photovoltaic, solar. Array, using, 1%. Efficient, selenium, cells on a New, York City, roof, in, 1884.
However. Development, of. Solar technologies. Stagnated. In the early 20th, century in, the face of the increasing. Availability. Economy. And utility. Of coal and petroleum. In. 1974. It was estimated that. Only six, private homes, in all of North America, were entirely, heated. Or cooled by. Functional. Solar, power, systems. The. 1973. Oil embargo, and. 1979. Energy crisis. Caused a, reorganization. Of energy, policies. Around the world and brought renewed attention to. Developing solar. Technologies. Deployment. Strategies. Focused. On incentive. Programs, such, as the federal photovoltaic. Utilization. Program in, the u.s. and the sunshine, program, in Japan, other. Efforts. Included. The formation, of research, facilities in, the United, States, Surrey, now NREL. Japan. NEDO. And Germany. Fraunhofer, eyes. Between. 1970. And, 1983. Installations. Of photovoltaic. Systems. Grew, rapidly but. Falling oil prices in. The early, 1980s. Moderated. The growth of photovoltaics. From. 1984. To 1996. Topic. Mid-1990s. To early. 2010's. In, the mid-1990s. Development. Of both residential. And, commercial rooftop. Solar as well as utility-scale. Photovoltaic. Power. Stations, began, to accelerate, again, due to supply, issues, with oil and natural, gas global. Warming, concerns, and the improving, economic, position. Of PV, relative. To other energy, technologies. In. The early, 2000s. The adoption, of feed-in. Tariffs, a policy. Mechanism. That gives renewables. Priority. On the grid and defines, a fixed price for the generated. Electricity. Led. To a high level of investment, security. And to a soaring, number, of PV, deployments. In Europe. Topic. Current. Status. For. Several, years, worldwide. Growth, of solar PV was, driven by, European, deployment. But has since shifted to, Asia, especially. China, and Japan and, to, a growing number of countries, and regions all, over the world including but. Not limited to. Australia. Canada, Chile. India. Israel. Mexico. South, Africa. South, Korea, Thailand. And the United States. Worldwide. Growth, of photovoltaics, has. Averaged, 40, percent, per year from, 2000. To 2013, and. Total, installed, capacity reached. 303. Gigawatts, at the end of 2016. With. China having, the most cumulative. Installations. 78. Gigawatts, and Honduras. Having, the highest theoretical. Percentage. Of annual electricity, usage. Which, could be generated. By solar PV. 12.5. Percent. The. Largest. Manufacturers. Are located, in China. Concentrated. Solar power, CSP. Also. Started, to grow rapidly. Increasing. Its capacity. Nearly tenfold from. 2004. To 2013. Albeit. From a lower level and involving, fewer countries than, solar, PV, as. Of. The end of 2013. Worldwide, cumulative. CSP. Capacity. Reached three thousand, four hundred and, twenty five megawatts. Topic. Forecasts. In. 2010. The International. Energy Agency. Predicted. That global, solar PV, capacity could. Reach three thousand gigawatts, or eleven percent of, projected. Global electricity, generation. By, 2050. Enough. To generate. 4,500. Terawatt-hours, of, electricity. Four. Years later in. 2014. The agency. Projected. That under, its high. Renewables. Scenario. Solar, power, could, supply, 27. Percent of global electricity.
Generation. By, 2050. 16, percent, from PV, and 11%, from, CSP. Topic. Photovoltaic. Power. Stations. The. Desert, sunlight solar, farm, is a 550, megawatts, power plant, in, Riverside, County, California that. Uses, thin film CdTe. Modules. Made, by First Solar as, of. November, 2014. The. 550. Megawatt, Topaz, solar, farm was, the largest photovoltaic, power. Plant in the world, this. Was surpassed, by the. 579. Megawatt. Solar, star, complex. The. Current, largest, photovoltaic, power. Station. In the world is, longing chardin. Solar, Park in Ghana County, Ching, hai China. Topic. Concentrating. Solar, power, stations. Commercial. Concentrating. Solar power, CSP. Plants. Also, called solar. Thermal, power, stations. Were. First developed. In the 1980s. The. 377. Megawatt. See vampers, solar power, facility. Located. In California's. Mojave Desert. Is the world's, largest solar. Thermal power, plant, project. Other. Large, CSP. Plants, include, the soul Nova's solar power, station. 150. Megawatts, the, andasol, solar power, station. 150. Megawatts, and extra, Sall solar, power, station. 150. Megawatts, all in, Spain. The. Principal, advantage of. CSP, is, the ability to efficiently. Add thermal, storage, allowing. The dispatching. Of electricity. Over up to a 24-hour, period. Since. Peak electricity. Demand, typically, occurs at about 5:00 p.m. many, CSP. Power plants. Used three to five hours of thermal, storage. Topic. Economics. Topic. Cost. The. Typical, cost factors. For solar power include, the costs, of the modules, the, frame to hold them wiring. Inverters. Labor, cost, any land, that might be required, the, grid connection. Maintenance. And the solar, insulation. That location, will, receive. Adjusting. For inflation it, cost 96, dollars per watt for a solar module, in the mid-1970s. Process. Improvements. And the very large boost, in production. Have brought that figure, down to 68, cents, per watt in February. 2016. According, to data from Bloomberg. New Energy Finance. Palo. Alto California. Signed. The wholesale, purchase, agreement, in, 2016. That secured. Solar, power for, 3.7, cents, per kilowatt, hour and, in. Sunny Dubai, large-scale. Solar, generated. Electricity, sold. In, 2016. For just 2.9, nine cents, per kilowatt, hour, competitive. With any form, of fossil based.
Electricity. And. Cheaper. Than most. Photovoltaic. Systems. Use, no fuel, and modules. Typically, last 25. To, 40, years. Thus. Capital. Costs, make up most of the cost of solar power. Operations. And maintenance costs. For new utility-scale, solar, plants. In the US are estimated. To be nine percent, of the cost of photovoltaic, electricity. And. 17, percent of, the cost of solar thermal electricity. Governments. Have created. Various, financial. Incentives. To encourage the, use of solar power, such, as feed-in. Tariff, programs. Also. Renewable. Portfolio. Standards. Impose, a government. Man date that utilities. Generate. Or acquire certain, percentage. Of renewable power, regardless. Of increased, energy procurement. Costs. In. Most, states, RPS. Goals, can, be achieved by, any combination, of, solar, wind biomass. Landfill. Gas ocean. Geothermal. Municipal. Solid waste. Hydroelectric. Hydrogen. Or fuel, cell technologies. Topic. Levelized. Cost, of electricity. The. PV, industry is. Beginning, to adopt levelized, cost, of electricity, LCOE. As the, unit of cost. The. Electrical. Energy generated is. Sold in units, of kilowatt, hours. KWh. As, a. Rule, of thumb and, depending. On the local insulation. One watt peak of installed, solar PV. Capacity, generates. About one to two kilowatt. Hours, of electricity per. Year, this. Corresponds. To a capacity. Factor of, around 10 to 20 percent. The. Product, of the local, cost of electricity, in, the insulation. Determines. The break-even point. For, solar, power the. International. Conference on, solar, photovoltaic. Investments. Organized. By EPIA, has, estimated, that, PV. Systems, will pay back their investors. In 8 to 12 years as a. Result. Since. 2006. It has been economical. For investors, to install, photovoltaics. For. Free in return for, a long term power purchase. Agreement. 50%. Of commercial. Systems, in the United, States, were, installed, in this manner in. 2007. And over 90% by. 2009. Shijin. Grom has said that as of 2012. Unsubsidized. Solar, power, is already competitive, with, fossil fuels. In, India Hawaii, Italy. In Spain. He. Said we, are at a tipping point, no. Longer, o renewable. Power sources like, solar. And, wind a, luxury, of the rich. They. Are now starting to. Compete, in the real world, without, subsidies. Solar. Power, will, be able to compete, without, subsidies. Against. Convention. All power sources, in half the world by. 2015. Topic. Current. Installation. Prices. In. Its 2014. Edition. Of the technology. Roadmap, solar. Photovoltaic energy. Report. The International. Energy Agency. IEA. Published. Prices, for residential, commercial. And, utility-scale. PV. Systems. For eight major markets. As of 2013, see. Table, below. However. Dos SunShot. Initiative has, reported. Much lower u.s. installation. Prices. In. 2014. Prices. Continued. To decline the. SunShot, initiative modeled. U.s. system prices. To be in the range of one dollar and 80 cents, to three dollars and twenty-nine cents, for what, other. Sources. Identify. Similar, price ranges. Of one dollar and seventy cents to three dollars and 50 cents, for the different, market, segments. In the US and in the highly, penetrated. German, market, prices. For residential. And small commercial, rooftop. Systems, of up to 100. Kilowatts, declined. To one dollar and 36. Cents per watt one euro and 24. Cent the W, by the end of 2014. In. 2015. Deutsche. Bank estimated. Costs. For small residential. Rooftop. Systems, in the u.s. around two dollars and, ninety cents for what. Costs. For utility, scale systems. In China and India were estimated. As low as one dollar for, what. Topic. Grid, parity. Grid, parity the, point at which the cost of photovoltaic electricity. Is. Equal, to or cheaper, than the price of grid power is more, easily achieved in areas, with abundant Sun. And high costs, for electricity. Such, as in California and, Japan, in. 2008. The levelized, cost, of electricity, for. Solar PV was, 25. Cents, per kilowatt. Hour or, less in most of the OECD. Countries. By. Late 2011, the fully-loaded, cost, was predicted. To fall below, 15, cents per kilowatt. Hour for most of the OECD. And to reach 10 cents per kilowatt. Hour in sunnier, regions. These. Cost, levels, are driving, three emerging, trends, vertical. Integration, of the supply, chain, origination. Of Power Purchase, Agreements. PPAs, by, solar, power companies. An unexpected. Risk for traditional, power generation. Companies. Grid, operators. And wind turbine. Manufacturers. Grid, parity was, first reached in Spain, in 2013. Hawaii, and other islands, that otherwise, use, fossil, fuel diesel, fuel, to produce electricity. And, most, of the u.s. is expected, to reach grid, parity, by, 2015. In. 2007. General, electrics. Chief engineer. Predicted. Grid parity, without. Subsidies. In sunny parts, of the United, States by, around, 2015. Other companies.
Predicted. An earlier date the cost of solar power will, be below grid parity, for more, than half of residential. Customers. And 10%, of commercial. Customers. In the OECD as. Long, as grid electricity, prices. Do not decrease, through 2010. Topic. Productivity. By location. The. Productivity. Of solar power, in a region, depends. On solar, irradiance. Which, varies, through the day and is influenced. By latitude. And, climate. The. Locations. With highest annual solar, irradiance. Lie in the arid tropics, and subtropics. Deserts. Lying in low latitudes. Usually. Have few, clouds and can receive sunshine, for, more than 10 hours a day. These. Hot deserts, form, the global, Sun Belt circling. The world, this, belt consists. Of extensive. Swaths of land in, northern Africa, southern, Africa, Southwest. Asia Middle, East, and Australia as, well as the much smaller deserts. Of North and South America. Africa's. Eastern, Sahara, Desert, also, known as the, Libyan desert has, been observed, to be the sunniest, place on earth according. To NASA. Different. Measurements. Of solar irradiance. Direct. Normal irradiance. Global. Horizontal. Irradiance, a mapped below. Topic. Self-consumption. In, cases, of self, consumption, of the solar, energy the payback time is calculated, based, on how much electricity is. Not purchased. From the grid, for. Example. In Germany. With electricity, prices. Of twenty five cents, per kilowatt-hour and, insulation, of nine hundred, kilowatt, hours, per kilowatt, one KW, P will save two hundred and, twenty, five euros, per year and with an installation. Cost of one thousand, seven hundred euros. Per KW. P the system, cost will be returned, in less than seven years. However. In many cases the patterns. Of generation. And consumption, do not coincide, and some, or all of the energy, is fed back into the grid, the. Electricity. Is sold and at other times when. Energy is, taken from the grid electricity. Is bought. The. Relative, costs, and prices, obtained, affect, the economics. In many. Markets, the, price paid for sold, PV, electricity is. Significantly. Lower than the price of bought, electricity. Which incentivizes. Self, consumption. Moreover. Separate. Self consumption, incentives. Have been used, in eg. Germany. And Italy grid. Interaction. Regulation. Has also included. Limitations. Of grid feed-in, in some regions, in Germany, with high amounts of installed, PV, capacity. By. Increasing. Self consumption, the, grid feeding, can be limited, without curtailment. Which wastes, electricity. A good match between, generation. And consumption, is, key for high self, consumption. And should be considered, when deciding where. To install solar, power, and how to dimension. The installation. The. Match can be improved, with batteries, or controllable. Electricity. Consumption, however. Batteries. Are expensive and. Profitability. May require, provision. Of other services from. Him besides, self, consumption, increase. Hot. Water storage, tanks, with electric, heating, with heat pumps, or resistance. Heaters, can provide, low-cost, storage. For self-consumption. Of, solar power. Shiftable. Loads, such. As dishwashers. Tumble. Dryers and, washing, machines can. Provide, controllable. Consumption. With only a limited effect, on the users, but their effect on self, consumption. Of solar power may, be limited. Topic. Energy. Pricing. And incentives. The. Political. Purpose, of incentive, policies. For PV is to facilitate, an initial, small scale, deployment. To begin to grow the industry even where, the cost of PV is significantly. Above grid parity, to, allow the industry, to achieve, the economies, of scale, necessary. To reach grid, parity. The. Policies, are implemented, to promote, national, energy, independence.
High-tech. Job creation. And reduction. Of co2 emissions. Free. Incentive. Mechanisms. Are often used in combination as. Investment. Subsidies the, authorities. Refund, part, of the cost of installation, of, the system the, electricity. Utility. Buys PV. Electricity from. The producer. Under a multi-year. Contract at. A guaranteed, rate and so the renewable, energy, certificates. SRECs. Topic. Rebates. With. Investment. Subsidies the, financial. Burden, falls upon the taxpayer, while with feed-in. Tariffs, the extra, cost is distributed. Across the utilities. Customer. Bases. While. The investment. Subsidy. May be simpler. To administer. The main argument. In favor of feed-in. Tariffs, is the encouragement, of, quality. Investment. Subsidies are, paid out as a function, of the nameplate capacity of. The installed, system and, the independent. Of its actual, power yield over, time thus rewarding. The overstatement. Of power and tolerating. Poor durability. And maintenance. Some. Electric, companies, offer rebates. To the customers. Such, as Austin, Energy in Texas, which offers, two dollars, and fifty cents for what installed, up to fifteen, thousand, dollars. Topic. Net, metering. In, net metering, the price, of the electricity. Produced is. The same as the price supplied, to the consumer, and the consumer is. Billed on the difference, between, production. And consumption. Net. Metering, can usually be, done with, no changes. To standard, electricity. Meters, which, accurately, measure power in both directions, and, automatically. Report. The difference, and because it allows homeowners, and, businesses. To generate electricity. At, a different, time from consumption. Effectively. Using, the grid as a giant, storage, battery. With. Net metering deficits. Are built each month while, surpluses. Are rolled over to, the following, month. Best. Practices. Call for perpetual, rollover. Of kWh. Credits. Excess. Credits, upon, termination of, service are. Either lost, or paid, for at a rate ranging. From wholesale. To retail rate. Or above, as can, be excess, annual, credits. In. New Jersey annual. Excess, credits, are paid at the wholesale, rate as a leftover. Credits. When a customer. Terminates, service. Topic. Feed-in-tariffs. Fit. With. Feed-in, tariffs the financial. Burden, falls, upon the consumer. They. Reward, the number, of kilowatt, hours, produced, over, a long period, of time but. Because the rate is set by the authorities. It may result in, perceived. Overpayment. The. Price paid, per kilowatt, hour under. A feed-in tariff, exceeds. The price of grid electricity. Net. Metering refers. To the, case where the price paid, by the utility. Is the same as the price charged. The. Complexity. Of approvals. In California. Spain, and Italy has, prevented, comparable. Growth to Germany, even though, the return on, investment is. Better, in. Some, countries, additional. Incentives. Are offered, for BIPV. Compared, to standalone. PV. France. Plus 16, euro cents, per kilowatt. Hour compared. To semi, integrated. Or plus EU, are. 0.27. Per kilowatt. Hours, compared. To standalone. Italy, + EU our, 0.04. To 0.08%. E. Topic. Solar. Renewable. Energy. Credits. SRECs. Alternatively. SRECs. Allow. For a market, mechanism to, set the price of the solar generated. Electricity. Subsidy. In. This mechanism a, renewable. Energy, production, or, consumption, target. Is set and the utility. More technically, the load serving, entities is, obliged, to purchase, renewable energy. Or face, a fine, alternative. Compliance, payment. Or ACP. The. Producer. Is credited. For an SRE, see, for every 1000. Kilo, watt hours, of electricity, produced. If. The utility buys. This SR, EC, and retires, it they avoid paying, the ACP. In. Principle. This system, delivers, the cheapest, renewable, energy, since, the all solar, facilities. Are eligible, and can be installed in the most economic. Locations. Uncertainties. About, the future, value of SRECs. Have. Led to long term SR, EC, contract. Markets, to give clarity to the prices, and allow solar, developers. To pre-sell, and hedge their credits. Financial. Incentives. For photovoltaics. Differ. Across, countries, including. Australia, China. Germany. Israel. Japan. And the United States and. Even across states, within, the US. The. Japanese, government, through its Ministry. Of International, Trade and Industry ran. A successful, program. Of subsidies. From. 1994. To 2003.
By. The end of, 2004. Japan. Led the world in installed, PV, capacity with. Over 1.1. Gigawatts. In, 2004. The German, government, introduced. The first large-scale. Feed-in. Tariff, system, under, the German, Renewable, Energy Act which. Resulted. In explosive. Growth of PV, installations. In Germany. At, the outset, the fit was over, 3x, the retail, price or 8x, the industrial. Price. The. Principle. Behind the German, system, is a 20-year. Flat rate contract. The. Value, of new contracts. Is programmed. To decrease each year, in order to encourage the industry to, pass on lower costs, to the end-users, the. Program, has been more successful than. Expected. With over 1 gigawatt, installed. In. 2006. And political. Pressure is mounting to, decrease the tariffs to lessen the future, burden, on consumers. Subsequently. Spain. Italy, Greece. That. Enjoyed, an early success with, domestic. Solar thermal, installations. For hot water needs, and, France. Introduced. Feed-in. Tariffs. None. Have replicated the. Program, decrease, of fit in new contracts, though making the German, incentive. Relatively. Less and less attractive. Compared, to other countries. The. French and Greek fit, offer a high premium, EU, are. 0.55. Per kilowatt. Hours, for building, integrated. Systems. California. Greece, France. And, Italy have, 30, to 50 percent more, insulation. Than, Germany, making them financially. More attractive. The. Greek domestic. Solar. Roof. Programme, adopted. In June, 2009. For, installations. Up to 10 kilowatts has, internal. Rates of return, of 10 to 15% at. Current, commercial, installation. Costs, which furthermore. Is tax-free. In. 2006. California. Approved, the California. Solar Initiative, offering. A choice of investment. Subsidies, or fit for small and, medium, systems, and a fit for large systems. The, small system, fit of 39. Cents, per kilowatt-hour. Far. Less than EU countries. Expires. In, just five years and, the alternate. Epbb. Residential. Investment, incentive. Is modest, averaging. Perhaps, 20%, of, cost, all. California. Incentives. Are scheduled, to decrease, in the future depending. As a function. Of the amount of PV, capacity, installed. At. The end of, 2006. The Ontario, Power Authority.
OPA, Canada. Began its, standard. Offer program. A precursor. To the Green Energy Act and, the first in North America. For distributed. Renewable, projects, of less than 10 megawatts. The. Feed-in tariff, guaranteed. A fixed, price of 42. Cents, CDN, per kilowatt. Hour over. A period of 20, years. Unlike. Net metering, all the electricity. Produced, was sold to the OPA, at the given rate. Topic. Grid, integration. The. Overwhelming. Majority of, electricity. Produced. Worldwide, is, used immediately. Since, storage, is usually, more expensive and. Because traditional. Generators. Can adapt to demand. However. Both solar, power, and wind power, variable. Renewable, energy, meaning, that all available output. Must be taken, whenever it is available. By moving through, transmission, lines, to where it can be used now. Since. Solar energy. Is not available, at night storing. Its energy, is potentially. An important, issue particularly. In off-grid. And for future. 100%. Renewable, energy scenarios. To have continuous. Electricity. Availability. Solar, electricity. Is, inherently. Variable. And predictable. By time of day, location. And seasons. In. Addition. Solar is intermittent. Due today night, cycles. And unpredictable. Weather, how. Much of a special, challenge solar power, is in any given electric. Utility. Varies, significantly. In. A summer peak utility. Solar, is well matched to daytime, cooling, demands. In. Winter, peak utilities. Solar. Displaces. Other forms, of generation. Reducing. Their capacity. Factors. In. An electricity. System, without grid, energy storage. Generation. From stored, fuels, coal, biomass. Natural. Gas nuclear, must. Be go up and down in reaction. To the rise and fall of solar, electricity, see. Load following power plant. While. Hydroelectric. And natural, gas plants. Can quickly follow solar, being, intermittent. Due to the weather coal biomass, and. Nuclear, plants, usually take, considerable. Time to respond, to load and can only be scheduled. To follow the predictable. Variation. Depending. On local. Circumstances. 'beyond about twenty, to forty percent of, total generation. Grid-connected. Intermittent. Sources, like solar tend, to require investment. In some combination. Of grid interconnections. Energy. Storage, or demand-side, management. Integrating. Large amounts, of solar power with, existing, generation. Equipment has, caused, issues, in some cases. For. Example in. Germany. California. And Hawaii, electricity. Prices. Have been known to go negative when, solar, is generating. A lot of power, displacing. Existing. Base load generation, contracts. Conventional. Hydroelectricity. Works. Very well in, conjunction with, solar, power water can, be held back or released, from a reservoir, behind, a dam as required. Where. A suitable. River is not available, pumped-storage. Hydroelectricity. Uses. Solar power, to pump water to a high reservoir. On sunny, days then. The energy is recovered, at night and in bad weather by releasing, water, via. A hydroelectric, plant to, a low reservoir. Where, the cycle, can begin again. However. This, cycle, can lose 20%, of, the energy to, round-trip, in efficiencies. This, plus the construction. Costs, add to the expense, of implementing. High levels, of solar power. Concentrated. Solar power plants. May use thermal, storage, to, store solar, energy. Such, as in high-temperature, molten, salts. These. Salts, are an effective, storage, medium. Because, they are low cost have a high, specific, heat capacity. And can deliver heat at temperatures. Compatible. With conventional. Power systems. This. Method, of energy, storage, is, used for, example by, the solar to, power station. Allowing, it to store. 1.44. Terajoules. In its sixty-eight, cubic, meters storage, tank, enough, to provide full output for, close to thirty, nine hours.
With An efficiency, of about 99, percent in. Standalone. PV, systems, batteries. Are traditionally. Used to store excess, electricity. With. Grid-connected photovoltaic. Power. System. Excess, electricity. Can be sent to the electrical. Grid, net. Metering, and feed-in. Tariff, programs. Give, these systems, our credit, for the electricity. They produce. This. Credit offsets. Electricity. Provided, from, the grid when the system, cannot meet demand, effectively. Trading, with the grid instead, of storing, excess, electricity. Credits. Are normally, rolled over from, month to month and, any remaining, surplus. Settled, annually. When. Wind and solar are a small, fraction, of the grid power other, generation. Techniques, can adjust their output, appropriately. But as these forms, of variable. Power grow, additional. Balance on, the grid is needed, as. Prices. Are rapidly, declining, PV. Systems. Increasingly. Use rechargeable. Batteries, to store a surplus, to be later used, at night. Batteries. Used, for grid storage, stabilized. The electrical. Grid by leveling, out peak loads usually. For several, minutes and in rare cases for, hours, in. The future. Less expensive. Batteries, could play an important, role on the electrical. Grid as they can charge during, periods, when generation. Exceeds, demand and. Feed the stored energy into. The grid when demand is higher than generation. Although. Not permitted, under the US National, Electric, Code it is technically, possible to, have a plug-and-play. PV. Micro. Inverter a recent. Review article, found that careful, system, design, would enable such, systems, to meet all technical. Though not all safety, requirements. There. Are several companies selling. Plug-and-play, solar. Systems. Available. On the web but there is a concern, that if, people install. Their own it will reduce the enormous, employment. Advantage. Solar has, over, fossil fuels, common. Battery, technologies. Used, in today's home, PV, systems, include, the valve, regulated, lead, acid, battery, a modified. Version of, the conventional. Lead acid, battery, nickel, cadmium and, lithium ion batteries. Lead. Acid, batteries, are currently, the predominant. Technology. Used, in small-scale. Residential. PV systems. Due, to their high reliability, low. Self discharge and. Investment. And maintenance, costs. Despite, shorter, life time and lower energy, density. However. Lithium. Ion batteries. Have the potential, to, replace lead, acid, batteries, in the near future as they, are being intensively. Developed, and lower prices, are expected, due to economies of scale, provided. By large production, facilities. Such, as the giga fire 3:1, in. Addition, the li-ion, batteries. Of plug-in, electric cars, may, serve as a future, storage, devices, in, a vehicle to, grid system. Since. Most vehicles. Are parked an average, of, 95%, of the time their, batteries, could be used to let electricity. Flow from, the car to the powerlines, and back other. Rechargeable. Batteries. Used, for distributed. PV systems. Include. Sodium. Sulfur. And vanadium, redox, batteries. Two, prominent, types, of a molten, salt and, a flow battery. Respectively. The combination. Of wind and solar PV, has, the advantage. That the, two sources, complement. Each other because, the peak operating times. For, each system occur. At different times, of the day and year, the. Power generation. Of such solar hybrid. Power systems. Is therefore, more constant. And fluctuates. Less, than each of the two component. Subsystems. Solar. Power, is seasonal. Particularly. In northern, southern, climates. Away, from the equator, suggesting. A need for long-term seasonal. Storage in, a medium, such as hydrogen.
Or Pumped, hydroelectric. The. Institute, for solar, energy supply. Technology. Of the university. Of kassel pilot. Tested, a combined, power plant, linking, solar wind, biogas. And hydro, storage to, provide load. Following power from. Renewable, sources research. Is also undertaken. In this field of artificial. Photosynthesis. It. Involves. The use of nanotechnology. To. Store solar electromagnetic. Energy. In chemical bonds. By splitting, water to, produce hydrogen, fuel. Or then, combining. With carbon, dioxide to. Make biopolymers. Such as methanol. Many. Large, national. And regional research. Projects. On artificial. Photosynthesis. Now trying, to develop techniques. Integrating. Improved, light capture. Quantum. Coherence, methods. Of electron, transfer and, cheap catalytic. Materials. That operate, under a variety of, atmospheric. Conditions. Senior. Researchers. In the field have, made the public policy, case for a global, project, on artificial. Photosynthesis. To address critical, energy, security. And environmental. Sustainability. Issues. Topic. Environmental. Impacts. Unlike. Fossil fuel-based. Technologies. Solar, power, does, not lead to any harmful. Emissions during. Operation. But the production, of the panel's leads, to some amount of pollution. Topic. Greenhouse. Gases. The. Lifecycle, greenhouse gas. Emissions. Of solar power are in the range of 22. To 46, gram, g per kilowatt-hour. KWh. Depending. On if solar thermal, or solar, pv, is being analyzed. Respectively. With. This potentially. Being decreased, to 15 grams per, kilowatt. Hour in, the future. For. Comparison. Of weighted, averages. A combined. Cycle gas fired, power, plant, emits, some 400. To. 599. Grams per. Kilowatt. Hour an oil-fired. Power plant. 893. Grams, per, kilowatt. Hour a coal-fired, power. Plant. 915. To. 994. Grams, per, kilowatt. Hour or with carbon, capture and, storage some. 200. Grams per, kilowatt. Hour and, a geothermal, high-temp. Power plant, 91. To, 122. Grams per. Kilowatt. Hour. The. Lifecycle, emission. Intensity, of hydro, wind and nuclear power a lower than sollars as of 2011. As published, by the IPCC. And, discussed. In the article, lifecycle. Greenhouse gas. Emissions. Of energy, sources. Similar. To all energy sources were. There total life cycle, emissions primarily. Lay in the construction. And transportation, phase. The, switch to low-carbon. Power in the manufacturing. And transportation, of. Solar devices, would, further reduce carbon. Emissions. BP. Solar owns two, factories, built by solar, x one in maryland the other in virginia, in which all of the energy, used to manufacture solar. Panels. Is produced, by solar, panels a, one. Kilowatt system, eliminates. The burning, of approximately. 170. Pounds, of coal 300. Pounds, of carbon dioxide from. Being released into, the atmosphere and. Saves, up to 105. Gallons of, water consumption. Monthly. The US National. Renewable Energy, Laboratory. NREL. In, harmonizing. The disparate, estimates, of lifecycle. GHG. Emissions, for solar PV found. That the most critical, parameter. Was the solar insulation. Of the site, GHG. Emissions, factors. For PV solar are inversely, proportional. To insulation. For. A site with insulation, of.
1,700. Kilowatt. Hours, per meter - per years typical. Of southern Europe, NREL. Researchers. Estimated. GHG. Emissions, of 45. G co2e. Per kilowatt. Hour. Using. The same assumptions. At Phoenix, USA. With, insulation, of. 2400. Kilo, watt hours, per meter, -, per years the, GHG, emissions, factor, would be reduced, to 32. Grams of co2 per. Kilowatt, hour, the, New Zealand, parliamentary. Commissioner. For the environment found. That the solar PV, would have little impact on the country's, greenhouse, gas emissions. The. Country, already generates. 80%. Of its electricity, from, renewable. Resources, primarily. Hydroelectricity. And geothermal, and, national. Electricity, usage. Peaks on winter, evenings whereas, solar, generation. Peaks, on summer afternoons, meaning. A large uptake, of solar PV would, end up displacing. Other renewable. Generators. Before, fossil, fuel power plants. Topic. Energy. Payback. The. Energy, payback time, EP, bt of a power generating. System. Is the time required, to generate as, much energy as, is consumed, during, production and, lifetime, operation. Of the system. Due. To improving. Production. Technologies. That payback, time has been decreasing, constantly. Since the introduction, of, PV, systems, in the energy, market. In. 2000. The energy, payback time of, PV, systems. Was estimated. As 8 to 11 years and in, 2006. This was estimated. To be one point five to three point five years, for crystalline, silicon. PV systems. And 1 to 1.5 years. For, thin film technologies. S. Europe. These figures, fell to. 0.75. To 3.5. Years in, 2013. With an average of about two, years for crystalline, silicon. PV insist. Systems, another, economic. Measure closely. Related to the energy payback time is, the energy, returned, on energy invested. Er, Oei or energy, return, on investment. EROI. Which is the ratio of electricity. Generated. Divided. By the energy, required, to build and maintain the, equipment this, is not the same as the economic, return on investment. ROI which. Varies, according. To local, energy, prices. Subsidies. Available and. Metering, techniques. With, expected. Lifetimes, of 30 years, the, ER Oei of PV, systems. Are in the range of 10 to 30, thus, generating. Enough energy over, their lifetimes. To, reproduce, themselves many. Times, 6. To 31. Reproductions. Depending. On what type of material, balance. Of system, boss and the geographic. Location, of the system. You. Topic. Water, use. Solar. Power, includes. Plants, with, among the lowest water, consumption. Per, unit of, electricity. Photovoltaic. And, also, power plants. With among the highest, water consumption. Concentrating. Solar power with, wet cooling, systems. Photovoltaic. Power. Plants. Use very, little water for, operations. Life. Cycle, water consumption. For, utility, scale operations. Is estimated. To be 12 gallons, per megawatt, hour for. Flat panel, PV, solar. Only. Wind power which, consumes, essentially. No water during, operations. Has, a lower, water, consumption. Intensity. Concentrating. Solar, power plants. With wet cooling, systems, on the other hand, have the highest, water consumption. Intensities. Of any conventional. Type of electric, power plant, only, fossil. Fuel plants, with carbon, capture and storage, may, have higher water, intensities. A. 2013. Study comparing. Various sources, of electricity. Found. That the median water, consumption. During operations. Of concentrating. Solar power plants, with wet cooling, was, 810. Garr MW. HR, for, power tower, plants. And, 890. Gallons, MW. HR, for trough plants. This. Was higher than the operational. Water consumption. With, cooling, towers, for, nuclear. 720. Gallons, MW. HR, Col. 530. Gallons. MW. HR, or natural. Gas. 210. A, 2011. Study, by the National Renewable, Energy, Laboratory. Came, to similar, conclusions, for, power plants, with cooling, towers, water, consumption. During operations. Was. 865. Gallons. Whr. For, CSP, trough. 786.
Gallons, MW. HR, for, CSP, tower. 687. Gallons. MW. HR, for coal. 672. Gallons. MW. HR, for nuclear, and. 198. Gallons, MW. HR, for natural, gas. The. Solar, Energy Industries, Association. Noted. That the Nevada solar, one trough, CSP. Plant consumes. Eight hundred, and fifty, gallons, MW. HR. The. Issue of, water consumption. Is, heightened, because CSP. Plants, are often located in. Arid environments. Where water is scarce. In. 2007. The US Congress. Directed. The Department. Of Energy, to report, on ways to reduce water consumption. By, CSP. The. Subsequent. Report, noted, that dry cooling, technology. Was available that. Although more, expensive, to build and operate could, reduce, water consumption. By, CSP. By 91. To 95, percent a. Hybrid. Wet/dry, cooling, system, could reduce, water consumption. By, 32. To 58, percent a. 2015. Report by NREL. Noted. That of the 24, operating. CSP. Power plants. In the US for, used dry, cooling, systems. The. For dry cold, systems. Were the three power plants at the even, per solar power, facility. Near Barstow, California, and. The Genesis, solar energy. Project, in Riverside, County, California. Of. 15, CSP. Projects. Under construction or, development in. The US as of March 2015. Six were wet systems, seven. Were dry systems. One, hybrid and one unspecified. Although. Many older thermoelectric. Power plants, with once-through. Cooling or. Cooling, ponds, use more water than, CSP. Meaning, that more water passes. Through the system's, most, of the cooling water returns. To the water body, available. For other uses and they consume, less water by, evaporation. For. Instance, the median, coal power plant, in the US with once-through. Cooling uses. Thirty six thousand, three hundred and fifty, gallons, MW. HR, but, only. 250. Gallons, MW, HR less, than one percent, is lost through evaporation. Since. The, 1970s. The majority. Of u.s. power plants. Have used research. Lating systems, such as cooling, towers, rather than once through systems. Topic. Other issues. One. Issue that has often, raised concerns. Is, the use of cadmium, CD, a toxic. Heavy metal, that has the tendency, to accumulate. In ecological food. Chains. It. Is used as, semiconductor. Component. In cadmium, telluride, solar, cells, and, as buffer, layer for certain, cigs cells, in, the form of CDs. The. Amount of cadmium, used in thin film PV, modules, is relatively, small, 5, to 10 grams per, square meter, and with proper recycling, and, emission, control, techniques, in place the cadmium emissions from. Module production, can, be almost zero. Current. PV, technologies. Lead, to cadmium, emissions of. 0.3. To 0.9. Microgram. Per kilowatt-hour. Over. The whole lifecycle. Most. Of these emissions. Arise, through, the use of coal power for, the manufacturing. Of the modules, and coal, and lignite, combustion. Leads to much higher emissions. Of cadmium. Lifecycle. Cadmium, emissions from. Coal is 3.1. Microgram. Per kilowatt-hour. Lignite. 6.2. And natural. Gas, 0.2. Microgram. Per kilowatt. Hour. In. A lifecycle, analysis. It has been, noted, that if, electricity. Produced, by photovoltaic, panels. Were used to manufacture the, modules, instead, of electricity, from, burning, coal cadmium. Emissions from. Coal power usage. In the manufacturing. Process could. Be entirely, eliminated. In the case of crystalline, silicon. Modules, the, solder, material, that joins, together the copper strings, of the cells contains. About. 36%. Of lead PB. Moreover. The, paste used, for screen printing front. And back contacts. Contain, traces. Of PB. And sometimes, CD, as well, it. Is estimated, that about, 1,000. Metric tonnes of BB, have been used for 100. Gigawatts of, CC, solar, modules. However. There, is no fundamental. Need for led, in the solder alloy some, media sources, have, reported, that concentrated. Solar, power plants. Have injured, or killed large.
Numbers, Of birds due to intense, heat from the concentrated. Sun rays, this. Adverse, effect, does not apply to PV. Solar power, plants. And some, of the claims may, have been overstated. Or exaggerated. A 2014. Published, life cycle, analysis. Of land use for various. Sources, of electricity. Concluded. That the large-scale. Implementation. Of solar and wind potentially. Reduces. Pollution related. Environmental. Impacts. The. Study found, that the land use footprint. Given, in square, meter years, per megawatt, hour m-28, per megawatt, hour was. Lowest, for wind natural. Gas and rooftop, PV with. 0.26. 0.49. And. 0.59. Respectively. And followed. By utility. Scale solar, PV. With, 7.9. For. CSP, the. Footprint, was 9 and 14, using. Parabolic. Troughs and solar, towers, respectively. The. Largest, footprint, had coal-fired. Powerplants with, 18, meters to a per, megawatt, hour. Topic. Emerging. Technologies. You. Topic. Concentrator. Photovoltaics. Concentrator. Photovoltaics. CPV. Systems. Employ, sunlight. Concentrated. Onto photovoltaic. Surfaces. For the purpose, of electrical. Power production. Contrary. To conventional, photovoltaic. Systems. It uses, lenses, and curved mirrors, to focus sunlight onto small but, highly efficient, multi-junction. Solar, cells. Solar. Concentrators. Of all varieties. May, be used, and these are often mounted on, a solar, tracker, in order, to keep the focal, point upon, the cell as the Sun moves across, the sky. Luminescent. Solar, concentrators. When combined, with a PV solar cell, can also be, regarded, as a si PV, system. Concentrated. Photovoltaics, are. Useful, as they can improve, efficiency of. PV, solar panels. Drastically. In addition. Most solar, panels, on spacecraft, are, also made, of high efficient. Multi, Junction photovoltaic. Cells. To derive electricity. From sunlight when, operating. In the inner solar system. Topic. Flow, to voltaics. Floatable. Takes are an emerging form, of PV systems, that float on the surface of, irrigation, canals, water, reservoirs. Quarry, lakes and tailing. Ponds. Several. Systems, exist, in France, India. Japan, Korea. The United Kingdom. And the United States. These. Systems. Reduce, the need of valuable, land area, safe drinking, water that, would otherwise be lost through, evaporation and. Show a higher, efficiency. Of, solar, energy conversion, as, the, panels are kept at a cooler, temperature. Than they would be on land, although. Not floating, other, dual, use facilities, with. Solar, power include. Fisheries. Equals, equals, see also.