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dylan purner

Business Opportunities Assessment for Solar Photovoltaic (PV) Market in Brazil - 0 views

  • The Brazilian government still awaits a reduction in solar prices to create a specific auction by the end of 2013 or the beginning of 2014. However, the Ministry of Mines and Energy (MME) does not demonstrate any signs of this happening.
  • In 2013, however, revenue and capacity installed are expected to double: projects will be delivered, the resolution 482/2012 will have a major impact, and X% of the National Association of Electric Energy’s (ANEEL’s) research and development (R&D) will conclude. Capacity installed expectations in 2013 will near X megawatts (MW); in 2014, X MW; in 2015, X MW; and beyond, faster expansion is expected. Currently, capacity installed for the solar market is X MW, but it is expected to reach X MW by 2017. The total possible capacity installed for Brazil is close to X gigawatts (GW). This market revenue will have a X% compound annual growth rate (CAGR) during the forecast period (2012–2017) due to ANEEL´s R&D, international events, and the resolution 482/2012 cost reductions. Now, market revenue is close to $X million and can reach $X million by 2017.
  • Distributed generation could grow faster with financial support, better service from energy concessionaries, and cost reductions; nonetheless, it will grow considerably.
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  • Distributed microgeneration: electricity generating system, with capacity installed less than or equal to
  • kilowatts (kW); uses solar energy connected to the distribution network through facilities of consumer units Distributed minigeneration: electricity generating system with a capacity installed greater than 100 kW and less than or equal to X MW for the same sources; connected to the distribution network through facilities of consumer units
blackmerbru98

fossil fuels BP - 0 views

BP Alternative Energy is focusing on those sectors of the energy industry where we can profitably grow our business. This has led us to focus on wind and biofuels, businesses that are material, sca...

wind solar fuel cell biofuel pollution fossil fuels

started by blackmerbru98 on 03 Oct 13 no follow-up yet
bonnjos98

How long have people been using geothermal energy? - Curiosity - 1 views

  •  
    "It may surprise you to know that the ancient Romans had central heating. They used geothermal energy - in the form of hot springs - to heat their homes. Geothermal heating wasn't used in an organized fashion since until the late 19th century when Boise, Idaho, piped in water from local hot springs to warm buildings. Now, geothermal energy is used globally. Reykjavik, Iceland, leads the world in use of geothermal energy, heating 95 percent of its buildings with heat from below the Earth's surface."
  •  
    "It may surprise you to know that the ancient Romans had central heating. They used geothermal energy - in the form of hot springs - to heat their homes. Geothermal heating wasn't used in an organized fashion since until the late 19th century when Boise, Idaho, piped in water from local hot springs to warm buildings. Now, geothermal energy is used globally. Reykjavik, Iceland, leads the world in use of geothermal energy, heating 95 percent of its buildings with heat from below the Earth's surface."
dextereli99

SOLAR POWER BENEFITS - 0 views

  • Advantages of solar power are many. Although solar power is an energy source that we have only recently tapped into, it may easily become the most important energy source of the future. • Solar power is a renewable and natural resource. • Solar power is non-polluting. Unlike oil, solar power does not emit greenhouse gases or carcinogens into the air. • Light and energy from the sun costs nothing. Once you purchase the equipment to collect and convert energy from the sun, it costs you nothing to run. • Solar cells require little maintenance. • Solar cells can last a lifetime. • Solar power is silent.
  • • Solar energy can be used to heat water, dry clothes, heat swimming pools, power attic fans, power small appliances, produce light for both indoors and outdoors, and even to power cars, among other things.
  • • Solar energy products can be very expensive. The initial cost is, perhaps, the main disadvantage of solar energy. • To reach maximum level of efficiency you need a relatively large area to install solar panels. • Depending where you live (Arizona vs. Alaska, around many shady trees or in the desert, etc.), you will get different results with solar energy systems.
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  • • If you have a really good solar energy system, one that produces even more energy than you use, your utility company might buy that extra energy from you. • When you use solar energy, you and your home become independent on foreign or other sources of energy which raise costs quickly. • To run solar water pumps, you do not even need to connect to a gas or power grid. • Solar energy cannot be produced at night or if there is a lot of pollution in the air or clouds over the sun.
  • • Of course, realize you can have a battery backup system for your solar energy system that will take care of the problems that could arise when the sun does not. • You can install solar energy in remote locations. • If there is a power outage, but you run on solar, you will still have electricity! • As your energy needs grow, you can add more solar panels
  • • Technology for solar energy is constantly improving.
jack wells

My Library for wind - 0 views

  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free.
  •  
    "One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free."
westkea00

Wave and Tidal Energy - 1 views

  • But it has only been in recent years that it has started to become more realistic due to advance in research and technology.
  • Wave and tidal energy harvesting has been around for a few decades. But it has only been in recent years that it has started to become more realistic due to advance in research and technology. Some speculates that wave and tidal energy can supply at least 10 percent of the world's energy consumption. How much power can be harvested is determined mainly on the wave activity. A map of wave heights is shown towards the end of the document.
  • This method works much the same way as wind turbines. However, since water is four times denser than air, the tidal turbine can be much smaller to generate the same amount of energy. The ideal water current is between 2-2.5 m/s, which is usually at depths of 20-30m within 1 km from the shore. A commercial scale turbine can produce 300 kWatts but this can scale up depending on the farm's size.
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  • Wave and tidal energy harvesting has been around for a few decades.
  • Wave and tidal energy harvesting has been around for a few decades
  •  
    Wave and tidal energy harvesting has been around for a few decades. But it has only been in recent years that it has started to become more realistic due to advance in research and technology.
  •  
    Wave and tidal energy harvesting has been around for a few decades. But it has only been in recent years that it has started to become more realistic due to advance in research and technology. Some speculates that wave and tidal energy can supply at least 10 percent of the world's energy consumption. How much power can be harvested is determined mainly on the wave activity. A map of wave heights is shown towards the end of the document.
lefebvrekat99

BIOFUELS: What are they? How can they be used as an energy source (either on-...(Q&A) - 0 views

  • ofuels can be derived from almost any type of "biomass," a broad term that refers to living or recently alive biological material. Because biomass is produced on a short time scale, it is considered a renewable resource. I will describe types of biofuels—ethanol, biodiesel, syngas, bio-hydrogen, biogas, and solid biofuel—and their use. I'll also identify the crops and wastes being used to produce biofuels, and some issues surrounding biofuel production. How are biofuels being used? Biofuels are already used to supply a small fraction of our energy needs, with significant opportunities to expand their use as infrastructure is developed. In addition to ethanol and biodiesel for transportation, biofuels are currently used for power production, heating and cooling of buildings, and the thermal needs of industry. Biomass is today the largest non-hydroelectric renewable source for electricity produced in the U.S. Most of this is produced in pulp and paper mills, which often generate electricity by burning wood chips, bark, or the sludges and "liquors" that are byproducts of the paper-making process. At the same time, they recover waste heat from electricity generation to meet the thermal needs of the mill. This highly efficient combination is referred to as combined heat and power (CHP) or cogeneration. The electricity generated may be used onsite and/or supplied to the local utility for distribution to the public.
mcgrawjac98

Wind Energy - 0 views

  • Wind Energy, like Solar Energy is fully sustainable, being generated by natural wind flows, which in the U.K. are reliable enough to guarantee a stable, near constant supply of energy. Wind Power can be easily set up, either at home (see related article) or on a larger scale, by energy suppliers keen to meet government targets to reduce carbon emissions that are produced by conventional power stations.
  •  
    "Wind Energy, like Solar Energy is fully sustainable, being generated by natural wind flows, which in the U.K. are reliable enough to guarantee a stable, near constant supply of energy. Wind Power can be easily set up, either at home (see related article) or on a larger scale, by energy suppliers keen to meet government targets to reduce carbon emissions that are produced by conventional power stations."
lemairenat98

Tidal power - Wikipedia, the free encyclopedia - 0 views

  • Tidal stream generators (or TSGs) make use of the kinetic energy of moving water to power turbines, in a similar way to wind turbines that use wind to power turbines. Some tidal generators can be built into the structures of existing bridges, involving virtually no aesthetic problems. [edit] Tidal barrage
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    "Tidal stream generator Main article: Tidal stream generator Tidal stream generators (or TSGs) make use of the kinetic energy of moving water to power turbines, in a similar way to wind turbines that use wind to power turbines. Some tidal generators can be built into the structures of existing bridges, involving virtually no aesthetic problems."
mcdermottaar99

Generate Your Own Wind Energy - 0 views

  • As with installing your own solar energy, installing wind energy will help to reduce carbon emissions, which damage the environment and will save money.
  • It's only downfall is possibly the visual impact it makes on the landscape: A tall 'small scale' generator could attract wide rebuttal from neighbours, and this is worth considering before embarking on a wind generation project. However, if you live in a remote area, which benefits from exposure to the wind, or have neighbours that are happy for you to go ahead with the project, installing wind power can be an economically viable way to capitalise on natural, renewable resources
  • A wind generator will cost in the region of £3'000 - £15'000, at about £3'000 per kilowatt.
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  • You can expect a wind generator to pay for itself in little over five years, and with conventional energy prices soaring, the dividends will increase with time.
dpurdy

Biofuel Guide - Introduction to Ethanol and Biodiesel - 0 views

  • First generation biofuel are those fuel derived from vegetable or animal fats/oils, starch or sugar with the use of modern technology.
    • dpurdy
       
      Gallons per acre In the perspective of land use and agricultural efficiency, ethanol seems to be a good choice. The reason is that about 420 gallons of ethanol can be generated per acre in contrast to 60 gallons of biodiesel per acre soybeans. Consequently, the cost of soybean oil would significantly increase if biodiesel production is increased as well.
  • 1. Let the base organic material (corn, sugarcane, wheat, etc) pass through a grinding meal to pulverize the selected material. 2. Then, liquefy it by placing the blend of water, grain powder and an enzyme that facilitates the breakdown of the grain compound into a high-heat cooker. 3. Cool it afterwards. Add another enzyme that will facilitate the conversion of starch into sugars which are then fermented, producing alcohol from the cooled mash. 4. Start the fermentation by adding yeast to the sugar mixture. The sugars will be broken down to ethanol (a form of alcohol) and carbon dioxide. 5. Distill the fermented mixture in order for the ethanol to separate from the solids. 6. Get rid of the water from the separated ethanol through a dehydration process.
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    "Cellulose ethanol production is newly discovered experimental processes which can breakdown cellulose in woody fibers. This would only mean that through this method, ethanol from crop wastes, trees and grasses can be derived. It is significantly better since trees and grasses require small amount of energy in comparison to grains that must be replanted annually. "
lefebvrekat99

The Biofuels FAQs: The Facts About Biofuels: Ethanol - 0 views

  • The U.S. consumes a little more than 20 million barrels of oil a day. The largest end uses are motor gasoline (9 million barrels) and diesel (4 million barrels). That works out to about 140 billion gallons of gasoline and 60 billion gallons of diesel a year. In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006.
  • The U.S. consumes a little more than 20 million barrels of oil a day. The largest end uses are motor gasoline (9 million barrels) and diesel (4 million barrels). That works out to about 140 billion gallons of gasoline and 60 billion gallons of diesel a year. In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006. In the Energy
  • The U.S. consumes a little more than 20 million barrels of oil a day. The largest end uses are motor gasoline (9 million barrels) and diesel (4 million barrels). That works out to about 140 billion gallons of gasoline and 60 billion gallons of diesel a year. In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006. In the Energy Policy Act of 2005, Congress enacted the Renewable Fuels Standard, which requires an annual increase in biofuels use to 7.5 billion gallons by 2012. The chart above details past levels of U.S. ethanol production and the minimum levels set by the Renewable Fuels Standard. In the 2006 State of the Union address, President Bush announced a goal of replacing “more than 75% of our oil imports from the Middle East by 2025.” According to the Department of Energy, meeting that goal will require 60 billion gallons of biofuels a year. A year later, the President accelerated the timetable and called for “20 in 10.”
  •  
    In 2006, the U.S. consumed nearly 5.4 billion gallons of ethanol, 12 percent of which was imported. Adjusting for its lower energy content, that amounted to about 2.5% of the total U.S. demand for gasoline. Biodiesel consumption was much lower, about 250 million gallons in 2006.
sankeyrya00

The Energy Story - Chapter 16: Wind Energy - 2 views

    • shannonlan97
       
      inside of turbine picture
  • Farmers have been using wind energy for many years to pump water from wells using windmills like the one on the right
  • When a boat lifts a sail, it is using wind energy to push it through the water. This is one form of work.
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  • Wind is also used to turn large grinding stones to grind wheat or corn, just like a water wheel is turned by water power.
  • n Holland, windmills have been used for centuries to pump water from low-lying areas.
  • Wind can be used to do work. The kinetic energy of the wind can be changed into other forms of energy, either mechanical energy or electrical energy
  • Blowing wind spins the blades on a wind turbine – just like a large toy pinwheel.
  • If the wind gets too high, the turbine has a brake that will keep the blades from turning too fast and being damaged.
  • You can use a single smaller wind turbine to power a home or a school. A small turbine makes enough energy for a house.
  •  
    "The blades of the turbine are attached to a hub that is mounted on a turning shaft. The shaft goes through a gear transmission box where the turning speed is increased. The transmission is attached to a high speed shaft which turns a generator that makes electricity."
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]
  •  
    Fuel cell cars are expensive.  The fuel cell costs a lot
dpurdy

Converting Coal into Electricity ~ All About Coal ~ American Coal Foundation - 1 views

  • The coal powder mixes with hot air, which helps the coal burn more efficiently, and the mixture moves to the furnace. The burning coal heats water in a boiler, creating steam. Steam released from the boiler powers an engine called a turbine, transforming heat energy from burning coal into mechanical energy that spins the turbine engine. The spinning turbine is used to power a generator, a machine that turns mechanical energy into electric energy. This happens when magnets inside a copper coil in the generator spin.
  • Electricity-generating plants send out electricity using a transformer, which increases the voltage of the electricity based on the amount required and the distance it must travel. Voltages are often as high as 500,000 volts at this point.  Electricity flows along transmission lines to substation transformers. These transformers reduce the voltage for use in the local areas to be served.  From the substation transformers, electricity travels along distribution lines, which can be either above or below the ground, to cities and towns. Transformers once again reduce the voltage—this time to about 120 to 140 volts—for safe use inside homes and businesses. The delivery process is instantaneous. By the time you have flipped a switch to turn on a light, electricity has been delivered.
    • dpurdy
       
      This previous paragraph is about how electricity gets to your home.
  •  
    today hindi news,today news talmi,hindi news www.killdo.de.gg
dpurdy

HowStuffWorks "How the Hydrogen Economy Works" - 3 views

  • In the hydrogen economy, there is no storehouse to tap into. We have to actually create the e­nergy in real-time.
  • There are two possible sources for the hydrogen: Electrolysis of water - Using electricity, it is easy to split water molecules to create pure hydrogen and oxygen. One big advantage of this process is that you can do it anywhere. For example, you could have a box in your garage producing hydrogen from tap water, and you could fuel your car with that hydrogen. Reforming fossil fuels - Oil and natural gas contain hydrocarbons -- molecules consisting of hydrogen and carbon. Using a device called a fuel processor or a reformer, you can split the hydrogen off the carbon in a hydrocarbon relatively easily and then use the hydrogen. You discard the leftover carbon to the atmosphere as carbon dioxide.
  • To have a pure hydrogen economy, the hydrogen must be derived from renewable sources rather than fossil fuels so that we stop releasing carbon into the atmosphere. Having enough electricity to separate hydrogen from water, and generating that electricity without using fossil fuels, will be the biggest change that we see in creating the hydrogen economy.
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  • In the future, barring some technological breakthrough, it seems likely that one of two things will happen to create the hydrogen economy: Either nuclear-power or solar-power generating capacity will increase dramatically.
  • The electrical-generation problem is probably the biggest barrier to the hydrogen economy
wellsann99

STELR :: wind ENERGY - 1 views

  • STEP 1: Moving air pushes against the blades of the turbine, which are tilted to the direction of the wind. This makes the blades spin. In the process, some of the kinetic energy of the moving air is transformed into the mechanical energy of the spinning blades. (The wind still has some kinetic energy as it flows away from the turbine.) STEP 2: The shafts and the gears inside the gear box transfer the mechanical energy of the turbine to the generator. (The gears make the drive shaft to the generator spin faster than the shaft connected to the blade hub.) STEP 3: The generator transforms mechanical energy into electrical energy.
  •  
    steps to converting win power to electricty
leonardsar99

How long has solar power been around? - Fort Smith Alternative Energy | Examiner.com - 0 views

  • Using the sun's power has been around as early as the 7th century B.C. when people were using it to build fires. It is hypothesized that in 2nd century B.C. Archimedes used the reflective surfaces of bronze shields to burn ships invading Syracuse. However, it was not until 1973 when the Greek navy actually experimented with the notion and successfully burned a wooden ship at 50 meters. Sunrooms were common in houses and public buildings in the 6th century A.D. These were so common that "sun rights" were given to individuals. Swiss scientist Horace de Saussure was credited with building the world’s first solar collector in 1767. For a more descriptive timeline, this timeline lists the milestones in the historical development of solar technology from the 7th century B.C. up to today.
  • Using the sun's power has been around as early as the 7th century B.C. when people were using it to build fires. It is hypothesized that in 2nd century B.C. Archimedes used the reflective surfaces of bronze shields to burn ships invading Syracuse. However, it was not until 1973 when the Greek navy actually experimented with the notion and successfully burned a wooden ship at 50 meters. Sunrooms were common in houses and public buildings in the 6th century A.D. These were so common that "sun rights" were given to individuals. Swiss scientist Horace de Saussure was credited with building the world’s first solar collector in 1767. For a more descriptive timeline, this timeline lists the milestones in the historical development of solar technology from the 7th century B.C. up to today.
  •  
    how long has solar energy been around?
sokolkyl00

Solar Power Energy Information, Solar Power Energy Facts - National Geographic - 0 views

  • Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
  • In one technique, long troughs of U-shaped mirrors focus sunlight on a pipe of oil that runs through the middle. The hot oil then boils water for electricity generation. Another technique uses moveable mirrors to focus the sun's rays on a collector tower, where a receiver sits. Molten salt flowing through the receiver is heated to run a generator.
  • Despite the drawbacks, solar energy use has surged at about 20 percent a year over the past 15 years, thanks to rapidly falling prices and gains in efficiency. Japan, Germany, and the United States are major markets for solar cells. With tax incentives, solar electricity can often pay for itself in five to ten years.
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  • Solar energy is lauded as an inexhaustible fuel source that is pollution and often noise free. The technology is also versatile.
  •  
    " Today, the technology produces less than one tenth of one percent of global energy demand."
  •  
    Intriguing facts about the suns energy on how they use it on oil and the drawback 
  •  
    Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
labrumbra99

A Basic Overview of Fuel Cell Technology - 0 views

  • they generate electricity with very little pollution—much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
  • Scientists and inventors have designed many different types and sizes of fuel cells in the search for greater efficiency, and the technical details of each kind vary
  • in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now “ionized,” and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
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  • But in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now �ionized,� and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
  • Every fuel cell also has an electrolyte, which carries electrically charged particles from one electrode to the other, and a catalyst, which speeds the reactions at the electrodes. Hydrogen is the basic fuel, but fuel cells also require oxygen. One great appeal of fuel cells is that they generate electricity with very little pollution–much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
  • A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes.
  • fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode.
  • One detail of terminology:
  • Oxygen enters the fuel cell at the cathode and, in some cell types (like the one illustrated above), it there combines with electrons returning from the electrical circuit and hydrogen ions that have traveled through the electrolyte from the anode. In other cell types the oxygen picks up electrons and then travels through the electrolyte to the anode, where it combines with hydrogen ions. The electrolyte plays a key role. It must permit only the appropriate ions to pass between the anode and cathode. If free electrons or other substances could travel through the electrolyte, they would disrupt the chemical reaction. Whether they combine at anode or cathode, together hydrogen and oxygen form water, which drains from the cell. As long as a fuel cell is supplied with hydrogen and oxygen, it will generate electricity. Even better, since fuel cells create electricity chemically, rather than by combustion, they are not subject to the thermodynamic laws that limit a conventional power plant (see "Carnot Limit" in the glossary). Therefore, fuel cells are more efficient in extracting energy from a fuel. Waste heat from some cells can also be harnessed, boosting system efficiency still further
  •  
    "A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes."
  •  
    "A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode."
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