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crandallchr98

Hydrogen Fuel Cells - Disadvantages - 0 views

  • Fuel cells are currently very expensive, but since they have a simple construction, mass production costs would become extremely low. 
  • Prototype fuel cells last only 1/5th as long as would be needed to make fuel cells cost-effective.
  • They are energy losers because it costs more to produce hydrogen than is earned by using hydrogen in fuel cells:  Electricity generated by fuel cells in cars costs thousands of dollars per kilowatt:  This would have to fall by a factor of 10 for fuel cells to become economically viable.
bureaumar98

Biofuels - Solid, liquid, or gas fuels made from biomass - 0 views

  • Biofuels are produced from living organisms or from metabolic by-products (organic or food waste products). In order to be considered a biofuel the fuel must contain over 80 percent renewable materials
bishophan00

Wind Energy America - FAQs - 1 views

  • Simply put, an average one megawatt wind turbine will produce enough energy for the annual needs of 350 average households. The amount of energy produced by a turbine varies depending on several factors, namely the size and reliability of the turbine, and the speed that the wind is blowing. These factors together produce the turbine’s capacity. Typically modern turbines range in size from 660 kilowatts to over 3 megawatts of capacity. They are placed in fairly windy locations with minimum wind speeds in the range of six meters per second (around 13 miles per hour). Wind turbines generally run at 30 to 40 percent capacity, so a 1 MW turbine could produce around 3 million KWh of electricity in a year.
  • , wind energy could provide 20% of America’s electricity.
  • According to the American Wind Energy Association, the total U.S. production of wind power is around 25 gigawatts
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    "Simply put, an average one megawatt wind turbine will produce enough energy for the annual needs of 350 average households. The amount of energy produced by a turbine varies depending on several factors, namely the size and reliability of the turbine, and the speed that the wind is blowing. These factors together produce the turbine's capacity. Typically modern turbines range in size from 660 kilowatts to over 3 megawatts of capacity. They are placed in fairly windy locations with minimum wind speeds in the range of six meters per second (around 13 miles per hour). Wind turbines generally run at 30 to 40 percent capacity, so a 1 MW turbine could produce around 3 million KWh of electricity in a year."
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    today's wind power
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    How much wind power is currently being produced in the United States? According to the American Wind Energy Association, the total U.S. production of wind power is around 25 gigawatts. New wind projects made up 42% of the U.S.'s total new power-producing capacity constructed in 2008, adding 8.4GW of new facilities into the grid.
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    What is wind power? Wind power is the result of using the wind to generate electricity. In the past windmills were used to grind grain or pump water. Today, a large wind turbine can power all the electricity needs of at least 350 homes.
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    , wind energy could provide 20% of America's electricity. Today's wind turbines are very different from the windmills of the past. Moder
dpurdy

Hydrogen vehicle - Wikipedia, the free encyclopedia - 2 views

  • As of October 2009, Fortune magazine estimated the cost of producing the Honda Clarity at $300,000 per car
  • by 2010, the Department of Energy estimated that the cost had fallen 80% and that such fuel cells could be manufactured for $51/kW,
  • When compared to ICE vehicles using gasoline, however, fuel cell vehicles using hydrogen produced from natural gas reduce greenhouse gas emissions by 60%
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    • dpurdy
       
      so an internal combustion engine releases more co2 than a fuel cell that uses natural gas as its hydrogen source. 
  • Hydrogen fuel does not occur naturally on Earth and thus is not an energy source, but is an energy carrier. Currently it is most frequently made from methane or other fossil fuels. However, it can be produced from a wide range of sources (such as wind, solar, or nuclear) that are intermittent, too diffuse or too cumbersome to directly propel vehicles. Integrated wind-to-hydrogen plants, using electrolysis of water, are exploring technologies to deliver costs low enough, and quantities great enough, to compete with traditional energy sources.[1]
  • While methods of hydrogen production that do not use fossil fuel would be more sustainable
  • The challenges facing the use of hydrogen in vehicles include production, storage, transport and distribution.
  • The hydrogen infrastructure consists mainly of industrial hydrogen pipeline transport and hydrogen-equipped filling stations like those found on a hydrogen highway. Hydrogen stations which are not situated near a hydrogen pipeline can obtain supply via hydrogen tanks, compressed hydrogen tube trailers, liquid hydrogen tank trucks or dedicated onsite production.
  • Hydrogen fuel does not occur naturally on Earth and thus is not an energy source, but is an energy carrier. Currently it is most frequently made from methane or other fossil fuels. However, it can be produced from a wide range of sources (such as wind, solar, or nuclear) that are intermittent, too diffuse or too cumbersome to directly propel vehicles. Integrated wind-to-hydrogen plants, using electrolysis of water, are exploring technologies to deliver costs low enough, and quantities great enough, to compete with traditional energy sources.[2]
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    Fuel cell cars are expensive.  The fuel cell costs a lot
sconzomic99

Today's Climate Change | A Student's Guide to Global Climate Change | US EPA - 2 views

  • Burning fossil fuels releases carbon dioxide, a heat-trapping gas, into the atmosphere, which is the main reason why the climate is changing.
  •  
    What is climate change
dpurdy

Winds, Waves, Tides - Ocean Energy | Environmental News, Articles & Information | Global Warming News | EcoWorld - 2 views

  • Can Already Cost Under $.06 per Kilowatt Hour * Pneumatic devices, such as the oscillating water column (OWC), use wave motion to compress and decompress air, and drive a turbine. * Float-based devices utilise a buoyant float moving with the waves, reacting against a sea bed anchor in order to harness energy. * Spillover devices utilise wave height to replenish a reservoir of seawater, which runs a turbine. * Raft-type devices use the relative motion of adjacent rafts or pontoons to harness wave energy. * Moving-body devices articulate in the water, inducing motion, which may be used to drive a hydraulic motor.
  • Tidal stream devices extract energy from the diurnal flow of tidal currents (caused by the gravitational pull of the moon). Unlike wind and wave power, tidal streams offer entirely predictable output. However, as the lunar cycle is of around 25 hours’ duration, the timing of peak outputs differs by around an hour each day and tidal energy cannot be guaranteed at times of peak demand.
  • However, several large grid-connected demonstration projects are expected to enter the water in the near future. Tidal stream is thus a few years behind wave energy.
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  • Marine Current Turbines is about to field test a submerged 300 kW tidal turbine off Devon in the United Kingdom
  • The manufacturers of all these devices expect to deliver energy at a cost of 10-14 US cents per kWh, falling to below 6 US cents as experience grows and technologies mature
  • Power generation using wave energy is at a much earlier stage of development. Wave energy offers more predictable outputs than wind, but in early 2003 there was only around one megawatt of generating capacity installed worldwide, all of it essentially with demonstration prototypes. Proposed projects are likely to take this to about 6 MW over the next few years. The wave industry is characterised by a wide variety of novel devices
dpurdy

Advantages of Geothermal Energy - What are the Advantages of Geothermal Energy? - 0 views

  • Geothermal Energy produces no pollution. There are virtually no greenhouse gases given off. There is no pollution.
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dpurdy

Biomass Fuel - The Basics of Biomass Fuel - 1 views

  • Biomass fuel refers to anything that can either burn or decompose. Other terms are biomass energy or biofuel. The prefix "bio" refers to life.
  • Also utilizing the source of bioenergy reduces pollution, helps control carbon dioxide emissions ( Remember, plants take in CO2 which will offset emissions)
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    Biomass fuel refers to anything that can either burn or decompose. Other terms are biomass energy or biofuel. The prefix "bio" refers to life.
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dpurdy

Define Wind Energy - Here are Wind Energy Facts - 0 views

  • In scientific terms, wind energy is the "force" of winds blowing across the earth’s surface ("Wind Energy"). Wind is caused by uneven heating on the earth’s surface. The equator region receives more heat than say, Antarctica.
  • That heat tries to move from hotter to colder regions. Wind energy was first harvested centuries ago, when early windmills were used to power millstones, pumps, and forges
  • The amount of kinetic energy within Earth's atmosphere is equal to about 10,000 trillion kilowatt-hours.
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dpurdy

Hydrogen Fuel Alternative - 1 views

  • Just as solar, hydro and biomass energy has been utilized for thousands of years, hydrogen technology as a fuel source has also been known for over 150 years.
  • Hydrogen is a simple element - an atom with only one proton and one electron. It is also the most plentiful element in the universe. Despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on the Earth - it is always combined with other elements.
  • Water, for example, is a combination of hydrogen and oxygen. Hydrogen can be separated from hydrocarbons by applying heat, a process known as "reforming" hydrogen.
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filionmar99

EIA Energy Kids - Biofuels - 0 views

  • "Biofuels" are transportation fuels like ethanol and biodiesel that are made from biomass materials.
  • Ethanol and biodiesel are usually more expensive than the fossil fuels that they replace, but they are also cleaner-burning fuels, producing fewer air pollutants.
  • What Is Ethanol? Ethanol is an alcohol fuel made from the sugars found in grains, such as:
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  • Most of the ethanol used in the United States today is distilled from corn
  • As a transportation fuel, ethanol can be used as a total or partial replacement for gasoline
  • Unlike gasoline, pure ethanol is nontoxic and biodegradable; it quickly breaks down into harmless substances if spilled.
  • Ethanol and ethanol-gasoline mixtures burn cleaner and have higher octane than pure gasoline, but have higher "evaporative emissions" from fuel tanks and dispensing equipment. These evaporative emissions contribute to the formation of harmful, ground-level ozone and smog.
  • Ethanol may be considered to be carbon-neutral because the plants that are used to make fuel ethanol (such as corn and sugarcane) absorb CO2 as they grow and may offset the CO2 produced when ethanol is made and burned.
  • However, in some parts of the world, large areas of natural vegetation and forests have been cleared and burned to grow soybeans and palm oil trees to make biodiesel
  • Fueling engines with biodiesel has just started to catch on, but it isn't a new idea. Before petroleum diesel fuel became popular, Rudolf Diesel, the inventor of the diesel engine in 1897, experimented with using vegetable oil (biodiesel) as fuel.
  • Biodiesel as a Transportation Fuel A Bus Powered by Soybean Oil Source: Stock photography (copyrighted) Most trucks, buses, and tractors in the United States use diesel fuel.
  • Using a gallon of biodiesel produced in the United States avoids the CO2 emissions that result from burning about a gallon of petroleum diesel. Biodiesel may be considered to be carbon-neutral because the plants that are used to make it, such as soy beans and palm oil trees, absorb carbon dioxide (CO2) as they grow and may offset the CO2 produced when biodiesel is made and burned.
  • Biodiesel is a renewable fuel that can be used instead of diesel fuel, which is made from petroleum. Biodiesel can be made from vegetable oils, animal fats, or greases. Most biodiesel today is made from soybean oil. About half of biodiesel producers are able to make biodiesel from used oils or fats, including recycled restaurant grease.
  • early all gasoline so
  • Nearly all gasoline sold now in the U.S. contains some ethanol.
  • About 99% of the fuel ethanol consumed in the U.S. is added to gasoline in mixtures of up to 10% ethanol and 90% gasoline.
  • he U.S. Environmental Protection Agency ruled in October 2010, that cars and light trucks of model year 2007 and newer can use E15
dpurdy

Fuel Cells - Electrochemical Power - 1 views

  • Hydrogen as the Main Fuel of the Future Over the last decades hydrogen, (H2) has gained more and more attention as an environmentally friendly fuel and storage medium. Combustion of pure hydrogen produces only water as exhaust. Hydrocarbon and carbon oxide emissions can only come from motor oil in the combustion chamber. Nitrous oxide emissions result from the nitrogen content in the air and increase exponentially with the combustion temperature. By using H2 in fuel cells, practically no pollution occurs. In this respect, hydrogen offers emission levels that are much lower than existing and future standards.
  • Hydrogen is the most common of all elements in the universe.
  • The desire for a long-term transition to a hydrogen society is mainly based on the need to reduce polluting and climate-affecting emissions and the concern about depletion of fossil fuel resources. Today about 90 % of the world's energy consumption is covered by fossil fuels, and most of this comes from a limited number of regions in the world. Even if hydrogen will be used on a large scale in the future, there is still a need for an energy source to produce it. Renewable energy technology such as hydro electricity, wind, wave and solar power are in principle available, but are not yet mature for mass production and/or fully developed. 
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crandallchr98

Fuel Cell Markets - Advantages & Benefits of Fuel Cell & Hydrogen Technologies - 2 views

  • Advantages by Application Telecoms CHP Fuel Cell Generators Electric Vehicles - APU's and Range Extenders Fuel Cell Forklifts Marine Power Portable Power
  • Low Emissions – Using hydrogen, PEM fuel cells only emit water at the point of use. Even when using hydrocarbon fuels, fuel cells emit considerably less emissions than other combustion based technologies, this is for two reasons. Firstly their higher efficiency means they require less fuel to generate the same energy and secondly because there is no combustion, there are negligible NOx or SOx emissions and no particulate emissions.
  • Reliability & Maintenance – The only moving parts in fuel cells are involved with water, heat and air management (pumps, blowers, compressors). When compared to internal combustion engines, there are considerably less moving parts and these require less maintenance (no oil changes every 150 hours). Less maintenance means less site visits or trips to the garage and reduced operating costs. Fuel cells can be monitored remotely and any problems dealt with quickly.
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  • Few moving parts means all you will ever hear of a fuel cell is either a compressor, blower or pump
  • Hydrogen is the lightest of all gases and disperses very quickly, it is also non-polluting and hazardous to the surrounding environment (unlike gasoline a spillage / leak will not cause an environmental disaster). Hydrogen, like natural gas and petrol, is a fuel and will burn when ignited. Hydrogen is only explosive when it is able to build up in a enclosed space, which is very difficult as it has a habit of escaping (hydrogen is the smallest of all elements). As long as appropriate safety procedures are followed, as they should with any fuel, hydrogen is a safe fuel.
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    Advantages & Benefits of Hydrogen and Fuel Cell Technologies High Efficiency - Like generators and other engines, fuel cells are energy conversion devices - they convert stored energy within a fuel into usable energy. A fuel cell uses an electrochemical reaction to extract energy directly in the form of heat and electricity, both of which can be utilised at the point of generation.
dpurdy

Wave Energy Wave Power Clean Renewable Electricity Generation - Wavegen - 1 views

  • Ocean waves are a tertiary form of solar energy, in that unequal heating of the Earth’s surface generates wind, and wind blowing over water generates waves. Despite the fact that nearly 75% of the Earth’s surface is covered with water, waves are a largely unexplored source of energy, compared with the progress that has been made in harnessing the sun and wind.
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dpurdy

Wave power - Wikipedia, the free encyclopedia - 2 views

  • Waves are generated by wind passing over the surface of the sea. As long as the waves propagate slower than the wind speed just above the waves, there is an energy transfer from the wind to the waves.
  • The first known patent to utilize energy from ocean waves dates back to 1799 and was filed in Paris by Girard and his son.[12] An early application of wave power was a device constructed around 1910 by Bochaux-Praceique to light and power his house at Royan, near Bordeaux in France
  • Once the wave energy is captured at a wave source, power must be carried to the point of use or to a connection to the electrical grid by transmission power cables.[2
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  • The realistically usable worldwide resource has been estimated to be greater than 2 TW.[49][50] Locations with the most potential for wave power include the western seaboard of Europe, the northern coast of the UK, and the Pacific coastlines of North and South America, Southern Africa, Australia, and New Zealand. The north and south temperate zones have the best sites for capturing wave power. The prevailing westerlies in these zones blow strongest in winter. Waves are very predictable; waves that are caused by winds can be predicted five days in advance.[citation needed]
  • There is a potential impact on the marine environment. Noise pollution, for example, could have negative impact if not monitored, although the noise and visible impact of each design varies greatly.[5]. Other biophysical impacts (flora and fauna, sediment regimes and water column structure and flows) of scaling up the technology is being studied.[51] In terms of socio-economic challenges, wave farms can result in the displacement of commercial and recreational fishermen from productive fishing grounds, can change the pattern of beach sand nourishment, and may represent hazards to safe navigation.[52] Waves generate about 2,700 gigawatts of power
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dpurdy

EIA Energy Kids - Hydropower - 1 views

  • Tides are caused by the gravitational pull of the moon and sun, and the rotation of the Earth. Near shore, water levels can vary up to 40 feet due to tides. Dam of the Tidal Power Plant on the Estuary of the Rance River, Bretagne, France Source: Stock photography (copyrighted) Tidal power is more predictable than wind energy and solar power. A large enough tidal range — 10 feet — is needed to produce tidal energy economically.
  • The United States has no tidal plants and only a few sites where tidal energy could be produced economically. France, England, Canada, and Russia have much more potential to use this type of energy.
  • Tidal turbines are basically wind turbines in the water that can be located anywhere there is strong tidal flow. Because water is about 800 times denser than air, tidal turbines have to be much sturdier than wind turbines. Tidal turbines are heavier and more expensive to build but capture more energy.
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  • Waves are caused by the wind blowing over the surface of the ocean. There is tremendous energy in the ocean waves. It's estimated that the total potential off the coasts of the United States is 252 billion kilowatthours a year, about 6% of the United States' electricity consumption in 2010. The west coasts of the United States and Europe and the coasts of Japan and New Zealand are good sites for harnessing wave energy.
  • Many more ways to capture wave energy are currently under development. Some of these devices being developed are placed underwater, anchored to the ocean floor, while others ride on top of the waves. The world's first commercial wave farm using one such technology opened in 2008 at the Aguçadora Wave Park in Portugal.
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Wind Program: Frequently Asked Questions about Wind Energy - 2 views

  • What is wind energy? Wind energy (or wind power) refers to the process by which wind turbines convert the movement of wind into electricity. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Humans use this wind flow for many purposes: sailing boats, pumping water, and also generating electricity. Wind turbines convert the kinetic energy of the moving wind into electricity.
  • Birds and bats are occasionally killed in collisions with wind turbines. Like any form of development, wind projects can also negatively impact wildlife by altering habitat. Over the past two decades, the impact of wind development on birds has been greatly reduced by improvements in turbine design and particularly through improved project and turbine siting.
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    How do wind turbines work? A wind turbine works like a fan, but in reverse: instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the turbine's blades, which spin a shaft connected to a generator to make electricity.
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    wind energy facts.
dpurdy

Energy Resources: Wind power - 0 views

  • The Sun heats our atmosphere unevenly, so some patches become warmer than others. These warm patches of air rise, other air blows in to replace them - and we feel a wind blowing. We can use the energy in the wind by building a tall tower, with a large propellor on the top. The wind blows the propellor round, which turns a generator to produce electricity.
  • he best places for wind farms are in coastal areas, at the tops of rounded hills, open plains and gaps in mountains - places where the wind is strong and reliable. Some are offshore.
  • The best places for wind farms are in coastal areas, at the tops of rounded hills, open plains and gaps in mountains - places where the wind is strong and reliable. Some are offshore.
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  • Advantages Wind is free, wind farms need no fuel. Produces no waste or greenhouse gases. The land beneath can usually still be used for farming
  • Suitable areas for wind farms are often near the coast, where land is expensive.
  • Can be noisy. Wind generators have a reputation for making a constant, low, "swooshing" noise day and night, which can drive you nuts.
  • Wind power is renewable. Winds will keep on blowing, it makes sense to use them.
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Energy Resources: Geothermal power - 0 views

  • Geothermal energy has been used for thousands of years in some countries for cooking and heating.
  • How it works
  • Hot rocks underground heat water to produce steam. We drill holes down to the hot region, steam comes up, is purified and used to drive turbines, which drive electric generators.
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  • Advantages   Geothermal energy does not produce any pollution, and does not contribute to the greenhouse effect.
  • Once you've built a geothermal power station, the energy is almost free. It may need a little energy to run a pump, but this can be taken from the energy being generated.
  • The big problem is that there are not many places where you can build a geothermal power station. You need hot rocks of a suitable type, at a depth where we can drill down to them. The type of rock above is also important, it must be of a type that we can easily drill through.
  • Hazardous gases and minerals may come up from underground, and can be difficult to safely dispose of.
  • Is it renewable? Geothermal energy is renewable. The energy keeps on coming, as long as we don't pump too much cold water down and cool the rocks too much
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EIA Energy Kids - Solar - 2 views

  • Energy from the Sun The sun has produced energy for billions of years.  Solar energy is the sun’s rays (solar radiation) that reach the Earth. This energy can be converted into other forms of energy, such as heat and electricity.
  • Photovoltaic (PV devices) or “solar cells” change sunlight directly into electricity. Individual PV cells are grouped into panels and arrays of panels that can be used in a wide range of applications ranging from single small cells that charge calculator and watch batteries, to systems that power single homes, to large power plants covering many acres.
  • Solar energy systems do not produce air pollutants or carbon-dioxide
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  • Solar energy is by far the Earth's most available energy source. Solar power is capable of providing many times the total current energy demand. But it is an intermittent energy source, meaning that it is not available at all times.
  • Photons Carry Solar Energy Sunlight is composed of photons, or particles of solar energy. These photons contain various amounts of energy corresponding to the different wavelengths of the solar spectrum. When photons strike a photovoltaic cell, they may be reflected, pass right through, or be absorbed. Only the absorbed photons provide energy to generate electricity. When enough sunlight (energy) is absorbed by the material (a semiconductor), electrons are dislodged from the material's atoms. Special treatment of the material surface during manufacturing makes the front surface of the cell more receptive to free electrons, so the electrons naturally migrate to the surface.
  • Weather Affects Photovoltaics The performance of a photovoltaic array is dependent upon sunlight. Climate conditions (such as clouds or fog) have a significant effect on the amount of solar energy received by a photovoltaic array and, in turn, its performance.
  • History of the Photovoltaic Cell The first practical photovoltaic (PV) cell was developed in 1954 by Bell Telephone researchers examining the sensitivity of a properly prepared silicon wafer to sunlight. Beginning in the late 1950s, PV cells were used to power U.S. space satellites. PV cells were next widely used for small consumer electronics like calculators and watches and to provide electricity in remote or "off-grid" locations were there were no electric power lines. Technology advances and government financial incentives have helped to greatly expand PV use since the mid-1990s.
  • Using solar energy produces no air or water pollution and no greenhouse gases, but does have some indirect impacts on the environment.
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