Skip to main content

Home/ qmstech2/ Group items matching "making" in title, tags, annotations or url

Group items matching
in title, tags, annotations or url

Sort By: Relevance | Date Filter: All | Bookmarks | Topics Simple Middle
labrumbra99

Sierra Club Green Home » Blog Archive Fuel Cells: Environmental Benefits » Sierra Club Green Home - 0 views

  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • ...4 more annotations...
  • fuel cells
  • metimes produce a by-product of water or heat, though hydrogen fuel cells are considered more difficult to work with because of transportation and storage. More user friendly fuel cells which use natural gas with emissions that are much lower than those produced by conventional engines or energy sources and can reduce your carbon footprint by around 40%. Additionally, there are only negligible levels of NOx, SOx, Volatile organic compounds and particulates, which is a drastic improvement over traditional means of grid power production. Besides the decreased CO2 emissions and high efficiency rates, fuel c
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  •  
    " The environmental impact of fuel cells depends on the type of cell and the fuel being used. Fuel cells can run on a variety of sources, from natural gas to hydrogen to ethanol to biogas. Those that run on hydrogen can sometimes produce a by-product of water or heat, though hydrogen fuel cells are considered more difficult to work with because of transportation and storage. More user friendly fuel cells which use natural gas with emissions that are much lower than those produced by conventional engines or energy sources and can reduce your carbon footprint by around 40%. Additionally, there are only negligible levels of NOx, SOx, Volatile organic compounds and particulates, which is a drastic improvement over traditional means of grid power production. Besides the decreased CO2 emissions and high efficiency rates, fuel cells offer plenty of positive environmental impacts that should be considered by investors and consumers as solutions for cleaner energy are being further researched. 1. Fuel Conservation The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country! 2. Combined Heat and Power The greatest benefit from high powered, well designed fuel cells is the heat and power produced. This means that a property can reduce additional investments to heat their indoor areas or water. In this case, less is more. Since the heat can be redirected to heat water, the environmental benefit from this is the ability to heat the hot water supply without a need for a separate system as is the case with home solar."
fieldingbry99

Ch 12 Page 73: Sustainable Energy - without the hot air | David MacKay - 0 views

  • In open water, waves are generated whenever the wind speed is greater than about 0.5 m/s.
  • First, let’s clarify where waves come from: sun makes wind and wind makes waves.
  •  
    "First, let's clarify where waves come from: sun makes wind and wind makes waves."
pondalb98

Wind Energy Basics - 5 views

  • Wind is a form of solar energy. 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. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity.
  • The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity
  • The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power
  • ...19 more annotations...
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current
  • Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model
  • wind farm, and generate bulk electrical power
  • Utility-scale turbines range in size from 50 to 750 kilowatts. Single small turbines, below 50 kilowatts
  • Wind energy is very abundant in many parts of the United States. Wind resources are characterized by wind-power density classes, ranging from class 1 (the lowest) to class 7 (the highest). Good wind resources (e.g., class 3 and above, which have an average annual wind speed of at least 13 miles per hour) are found in many locations (see United States Wind Energy Resource Map)
  • free, renewable resource, so no matter how much is used today, there will still be the same supply in the future
  • clean, non-polluting, electricity. Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases
  • higher initial investment than fossil-fueled generators. Roughly 80% of the cost is the machinery, with the balance being site preparation and installation.
  • Although wind power plants have relatively little impact on the environment compared to fossil fuel power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and birds and bats having been killed (avian/bat mortality) by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants
  • remote locations far from areas of electric power demand (such as cities)
  • alternative uses may be more highly valued than electricity generation. However, wind turbines can be located on land that is also used for grazing or even farming
  • Wind is a form of solar energy. 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. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity.
  • The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity to power homes, businesses, schools, and the like.
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
  • Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines.
  • Wind is a form of solar energy
  • The terms "wind energy" or "wind power
  • describe the process by which the wind is used to generate mechanical power or electricity.
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
  •  
    "Wind is a form of solar energy. 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. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity."
  •  
    "Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines."
stockmanchl99

Biofuel Facts, Biofuel Information - National Geographic - 0 views

  • Biofuels have been around as long as cars have. At the start of the 20th century, Henry Ford planned to fuel his Model Ts with ethanol, and early diesel engines were shown to run on peanut oil.
  •  
    "On the face of it, biofuels look like a great solution. Cars are a major source of atmospheric carbon dioxide, the main greenhouse gas that causes global warming. But since plants absorb carbon dioxide as they grow, crops grown for biofuels should suck up about as much carbon dioxide as comes out of the tailpipes of cars that burn these fuels. And unlike underground oil reserves, biofuels are a renewable resource since we can always grow more crops to turn into fuel. Unfortunately, it's not so simple. The process of growing the crops, making fertilizers and pesticides, and processing the plants into fuel consumes a lot of energy. It's so much energy that there is debate about whether ethanol from corn actually provides more energy than is required to grow and process it. Also, because much of the energy used in production comes from coal and natural gas, biofuels don't replace as much oil as they use. For the future, many think a better way of making biofuels will be from grasses and saplings, which contain more cellulose. Cellulose is the tough material that makes up plants' cell walls, and most of the weight of a plant is cellulose. If cellulose can be turned into biofuel, it could be more efficient than current biofuels, and emit less carbon dioxide. "
olearydev99

What Is Hydrogen? (with picture) - 1 views

  •  
    "Hydrogen is a highly flammable chemical element that occurs in great abundance throughout the universe. In fact, this element makes up approximately 75% of the universe, by volume, and it appears in a very large number of compounds, especially those which make up various organic materials."
rutalil00

Wind power - Wikipedia, the free encyclopedia - 1 views

  • Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electricity, windmills for mechanical power, windpumps for water pumping or drainage, or sails to propel ships
  • Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electricity, windmills for mechanical power, windpumps for water pumping or drainage, or sails to propel ships.
  • The total amount of available power from the wind is considerably more than present human power use from all sources.[3] At the end of 2011, worldwide nameplate capacity of wind-powered generators was 238 gigawatts (GW), growing by 41 GW over the preceding year.[4] Wind power now (2010 data) has the capacity to generate 430 TWh annually, which is about 2.5% of worldwide electricity usage.[5][6] Over the past five years (2010 data) the average annual growth in new installations has been 27.6 percent. Wind power market penetration is expected to reach 3.35 percent by 2013 and 8 percent by 2018.[7][8] Several countries have already achieved relatively high levels of wind power penetration, such as 21% of stationary electricity production in Denmark,[5] 18% in Portugal,[5] 16% in Spain,[5] 14% in Ireland[9] and 9% in Germany in 2010.[5][10] As of 2011, 83 countries around the world are using wind power on a commercial basis
  • ...8 more annotations...
  • A large wind farm may consist of several hundred individual wind turbines which are connected to the electric power transmission network. Offshore wind power can harness the better wind speeds that are available offshore compared to on land, so offshore wind power’s contribution in terms of electricity supplied is higher.[11] Small onshore wind facilities are used to provide electricity to isolated locations and utility companies increasingly buy back surplus electricity produced by small domestic wind turbines. Although a variable source of power, the intermittency of wind seldom creates problems when using wind power to supply up to 20% of total electricity demand, but as the proportion rises, increased costs, a need to use storage such as pumped-storage hydroelectricity, upgrade the grid, or a lowered ability to supplant conventional production may occur.[12][13][14] Power management techniques such as excess capacity, storage, dispatchable backing supply (usually natural gas), exporting and importing power to neighboring areas or reducing demand when wind production is low, can mitigate these problems.
  • Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation, and uses little land. In operation, the overall cost per unit of energy produced is similar to the cost for new coal and natural gas installations.[15] The construction of wind farms is not universally welcomed, but any effects on the environment from wind power are generally much less problematic than those of any other power source
  • Wind is the movement of air across the surface of the Earth, affected by areas of high pressure and of low pressure.[35] The surface of the Earth is heated unevenly by the Sun, depending on factors such as the angle of incidence of the sun's rays at the surface (which differs with latitude and time of day) and whether the land is open or covered with vegetation. Also, large bodies of water, such as the oceans, heat up and cool down slower than the land. The heat energy absorbed at the Earth's surface is transferred to the air directly above it and, as warmer air is less dense than cooler air, it rises above the cool air to form areas of high pressure and thus pressure differentials. The rotation of the Earth drags the atmosphere around with it causing turbulence. These effects combine to cause a constantly varying pattern of winds across the surface of the Earth.[35]
  • Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power, windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships.
  • Compared to the environmental impact of traditional energy sources, the environmental impact of wind power is relatively minor in terms of pollution
  • Wind energy is the kinetic energy of air in motion, also called wind
  • ind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land.[2] The effects on the environment are generally less problematic than those from other powe
  • Wind power is very consistent from year to year but has significant variation over shorter time scales. The intermittency of wind seldom creates problems when used to supply up to 20% of total electricity demand,[5] but as the proportion increases, a need to upgrade the grid, and a lowered ability to supplant conventional production can occur.
  •  
    wind turbine stuff
  •  
    "Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power, windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships."
  •  
    Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land.[2] The effects on the environment are generally less problematic than those from other power sources. As of 2011, Denmark is generating more than a quarter of its electricity from wind and 83 countries around the world are using wind power on a commercial basis.[3] In 2010 wind energy production was over 2.5% of total worldwide electricity usage, and growing rapidly at more than 25% per annum. The monetary cost per unit of energy produced is similar to the cost for new coal and natural gas installations.[4]
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:
  • ...14 more annotations...
  • 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
fieldingbry99

Ocean Wave Energy - Pros and Cons - 1 views

  • But, on shore ocean wave energy generators will occupy extended lengths of coastline. And most of the coastlines of the world that have significant wave activity are either highly desired residential areas, or they are pristine wilderness.
  • Ocean wave energy is still in the development stages but it is already apparent that its impact on the environment could be relatively high compared to other renewable energies.
  • It is noteworthy that even these environmental impacts are far less than those of most fossil fuel plants.
  • ...1 more annotation...
  • electrical charges of less than $.05 per KWh; which makes it competitive with fossil fuel generators.
  •  
    " wave energy is very close to being competitive with installed costs that suggest electrical charges of less than $.05 per KWh; which makes it competitive with fossil fuel generators. But that figure doesn't take into account the fact that wave energy is intermittent and variable. Even in the most active wave areas, there are many days with little wave activity."
westkea00

Energy Resources: Wave power - 3 views

  • Waves are a powerful source of energy.
  • The problem is that it's not easy to harness this energy and convert it into electricity in large amounts.
  • wave power stations are rare
  • ...10 more annotations...
  • Once you've built a wave power station, the energy is free, needs no fuel and produces no waste or pollution
  • The energy is free - no fuel needed, no waste produced.
  • Not expensive to operate and maintain.
  • Can produce a great deal of energy.
  • Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem.
  • Ocean waves are caused by the wind as it blows across the sea. Waves are a powerful source of energy.
  • Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem
  • At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a turbine in this hole, which is turned by the air rushing in and out. The turbine turns a generator. A problem with this design is that the rushing air can be very noisy, unless a silencer is fitted to the turbine. The noise is not a huge problem anyway, as the waves make quite a bit of noise themselves.
  • At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a turbine in this hole, which is turned by the air rushing in and out. The turbine turns a generator. A problem with this design is that the rushing air can be very noisy, unless a silencer is fitted to the turbine. The noise is not a huge problem anyway, as the waves make quite a bit of noise themselves.
  • A company called Pelamis Wave Power are developing a method of offshore wave energy collection, using a floating tube called "Pelamis"
  •  
    " Advantages   The energy is free - no fuel needed, no waste produced. Not expensive to operate and maintain. Can produce a great deal of energy. Disadvantages Depends on the waves - sometimes you'll get loads of energy, sometimes almost nothing. Needs a suitable site, where waves are consistently strong. Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem. Must be able to withstand very rough weather."
  •  
    One of them works like a swimming pool wave machine in reverse. At a swimming pool, air is blown in and out of a chamber beside the pool, which makes the water outside bob up and down, causing waves.  
jack wells

Wind power - sustainable power generation from wind farms across the globe - 0 views

  • Wind power is safe, clean and increasingly affordable – with the potential for production on a much larger scale.Government support is crucial in ensuring the expansion of wind power. We believe such support should be transitional and limited. In the US, there is continuing uncertainty over the renewal of the production tax credit, which provides incentives to invest in wind energy. We are working with other wind energy suppliers to make an effective case for wind energy generation and the renewal of the production tax credit.Wind farms can provide large volumes of electricity (sometimes at a lower cost than conventional power generation)
  • Wind power is safe, clean and increasingly affordable – with the potential for production on a much larger scale.Government support is crucial in ensuring the expansion of wind power. We believe such support should be transitional and limited. In the US, there is continuing uncertainty over the renewal of the production tax credit, which provides incentives to invest in wind energy. We are working with other wind energy suppliers to make an effective case for wind energy generation and the renewal of the production tax credit.Wind farms can provide large volumes of electricity (sometimes at a lower cost than conventional power generation) Wind energy and the environment While wind farms can be an attractive alternative energy offering, they can also stir debate. During the planning stage for each new wind farm we assess the potential social and environmental impacts.The impact on wildlife and habitat The impact of wind farms on local residentsNoise from wind turbinesShadow flicker Interference with communications signalsWe then take steps to manage any negative impacts through engineering design changes, technology and other elements.
  • Wind power is safe, clean and increasingly affordable – with the potential for production on a much larger scale.Government support is crucial in ensuring the expansion of wind power. We believe such support should be transitional and limited. In the US, there is continuing uncertainty over the renewal of the production tax credit, which provides incentives to invest in wind energy. We are working with other wind energy suppliers to make an effective case for wind energy generation and the renewal of the production tax credit.
kramerjac99

Lockheed Martin · Wave and Tidal Energy - 0 views

  • Tremendous potential exists for clean energy in waves and tides. Lockheed Martin Mission Systems and Sensors (MS2) is leveraging decades of experience in designing and developing maritime systems into wave and tidal power systems. To do that, we have strategic relationships with key wave and tidal power technology providers. They will provide the technology to convert waves and tides into energy, and MS2 will provide the expertise to help make the systems work in harsh ocean environments and scalable for large-scale production. Wave power generates electricity using special buoys that use the rising and falling of ocean waves to generate electricity. MS2 is partnering with Ocean Power Technologies, Inc. (OPT) and WaveBob LLC to develop their respective wave energy systems for use in future utility-scale power generation projects. MS2 provides its expertise in systems integration, lean manufacturing, and test and optimization analysis to enhance OPT's and Wavebob’s wave power generation technology to utility-scale. Tidal power generating systems use underwater turbines designed to capture the kinetic motion of ebbing and surging ocean tides to produce power. MS2 provides design and manufacturing support to Singapore-based Atlantic Resources Corporation (ARC), which is testing its tidal turbines at the European Marine Energy Centre in Orkney, Scotland. MS2 is also exploring related technologies that can be adapted to shallow and low-rate tidal flows.
  •  
    what is used to make it work
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
  •  
    "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."
dpurdy

Why a hydrogen economy doesn't make sense - 0 views

  •  
    How inefficient it is to make hydrogen from electricity
dpurdy

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. Likewise, “tidal bridging” is a relatively new advancement that is gaining recognition as a more practical and beneficial way to generate tidal power.
    • dpurdy
       
      Good pic of tidal stream generator working
  •  
    "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. Likewise, "tidal bridging" is a relatively new advancement that is gaining recognition as a more practical and beneficial way to generate tidal power."
dpurdy

Energy Report - Hydrogen - 1 views

  • Hydrogen is colorless, odorless, tasteless and non-toxic. It is a gas at temperatures above -423° F and is highly diffuse, having a density approximately 14 times less than that of air. Because it is buoyant and diffusive, hydrogen dissipates quickly in open areas and can move through small spaces, which makes it difficult to store. Hydrogen is flammable over a broad range of gas concentration (from 4 to 74 percent), although its lower flammability limit – that is, the lowest temperature and pressure at which it will combust – is higher than those for some common fuels such as gasoline, propane or diesel.1 Hydrogen has been described as “the fuel of the future.” On Earth, hydrogen is found in combination with other elements such as carbon (hydrocarbons), oxygen (water) and nitrogen (ammonia). Although hydrogen may sometimes be used as a fuel, it is most often used as an energy carrier, such as electricity, and not an energy source. To make hydrogen a usable, stand-alone fuel, it must be separated from these other elements by chemical, thermal or electrochemical processes.
  • History British scientist Henry Cavendish identified hydrogen as a distinct element in 1766. Subsequent experiments by British and French scientists resulted in the first flight of a hydrogen balloon and the discovery that applying electricity to water can produce hydrogen and oxygen.
  • In the 1960s, NASA space capsules used hydrogen fuel cells for onboard electric power, heat and water.
  • ...1 more annotation...
  • The U.S. Department of Energy (DOE) does not maintain comprehensive statistics in this area, but the various demonstration projects suggest that there are some hundreds of hydrogen fuel cell vehicles on the road in the U.S.
  •  
    On Earth, hydrogen is found in combination with other elements such as carbon (hydrocarbons), oxygen (water) and nitrogen (ammonia). Although hydrogen may sometimes be used as a fuel, it is most often used as an energy carrier, such as electricity, and not an energy source. To make hydrogen a usable, stand-alone fuel, it must be separated from these other elements by chemical, thermal or electrochemical processes.
fiorinijam98

E85 | Making Ethanol - 0 views

  • Wheat or corn kernels are ground in a hammermill to expose the starch. The ground grain is mixed with water, cooked briefly and enzymes are added to convert the starch to sugar using a chemical reaction called hydrolysis. Yeast is added to ferment the sugars to ethanol. The ethanol is separated from the mixture by distillation and the water is removed from the mixture using dehydration.
jack wells

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.
  •  
    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.
  •  
    wind energy facts.
dpurdy

Energy Resources: Biofuels - 2 views

  • By "biofuels" on this page, I mean fuels for vehicles, such as "biodiesel" and "bioethanol" - although you can also use the term "biofuel" to cover any kind of fuel made from living materials or their waste.
  • How it works Biofuels are made from two main sources: Growing crops such as corn, sugar cane, soya or rapeseed; or from palm oil Growing algae
  • Biofuels are made from two main sources: Growing crops such as corn, sugar cane, soya or rapeseed; or from palm oil Growing algae
  • ...9 more annotations...
  • iofuels are potentially carbon-neutral, because although carbon dioxide is released when we burn them, carbon dioxide is taken in by the plants as they grow. However, energy is needed to grow the crops, harvest them, and to process the results into usable products - and most of this energy will be from fossil fuels for farm machinery and power stations.
  • Biofuels are potentially carbon-neutral, because although carbon dioxide is released when we burn them, carbon dioxide is taken in by the plants as they grow. However, energy is needed to grow the crops, harvest them, and to process the results into usable products - and most of this energy will be from fossil fuels for farm machinery and power stations.
  • Producing biofuels from crops means using large amounts of land to grow those crops - that means less land for food production. We must be careful to strike a balance between crops ofr fuel and crops for food.
  • Producing biofuels from crops means using large amounts of land to grow those crops - that means less land for food production. We must be careful to strike a balance between crops ofr fuel and crops for food.
  • Algae - that's pond scum - are microscopic water plants. They reproduce and photosynthesise fast, and the algae are then filtered out of the water and the lipids (oils) are used to make biodiesel.
  • It is claimed that growing plants to make biofuels will take in that carbon dioxide again. But biologists tell us that forests are not 'the lungs of the planet' after all - they give out as much CO2 as they absorb as the plants respire. It seems that it's plant plankton in the oceans that takes in most CO2 and gives out most oxygen.
  • It takes huge areas of land in order to grow crops for biofuels, although making biofuels from algae does not have this problem
  • Biofuel production is closer to being carbon-neutral than using fossil fuels.
  • Is it renewable? Biofuels are renewable, we can plant more of the crops or grow more of the algae.
  •  
    Most quality online stores. Know whether you are a trusted online retailer in the world. Whatever we can buy very good quality. and do not hesitate. Everything is very high quality. Including clothes, accessories, bags, cups. Highly recommended. This is one of the trusted online store in the world. View now www.retrostyler.com
dpurdy

EIA Energy Kids - Biomass - 1 views

  • Biomass is organic material made from plants and animals (microorganisms). Biomass contains stored energy from the sun. Plants absorb the sun's energy in a process called photosynthesis. The chemical energy in plants gets passed on to animals and people that eat them. Biomass is a renewable energy source because we can always grow more trees and crops, and waste will always exist. Some examples of biomass fuels are wood, crops, manure, and some garbage. When burned, the chemical energy in biomass is released as heat. If you have a fireplace, the wood you burn in it is a biomass fuel. Wood waste or garbage can be burned to produce steam for making electricity, or to provide heat to industries and homes.
  • Crops like corn and sugar cane can be fermented to produce ethanol. Biodiesel, another transportation fuel, can be produced from left-over food products like vegetable oils and animal fats.
  • Ethanol and biodiesel were the fuels used in the first automobile and diesel engines, but lower cost gasoline and diesel fuel made from crude oil became the dominant vehicle fuels. The Federal government has promoted ethanol use in vehicles to help reduce oil imports since the mid-1970s.
  • ...5 more annotations...
  • Compared to petroleum diesel, biodiesel combustion produces less sulfur oxides, particulate matter, carbon monoxide, and unburned and other hydrocarbons, but more nitrogen oxide.
  • Biofuels may be considered to be carbon-neutral because the plants that are used to make biofuels (such as corn and sugarcane for ethanol, and soy beans and palm oil trees for biodiesel) absorb CO2 as they grow and may offset the CO2 produced when biofuels are made and burned.
  • Growing plants for biofuels is controversial however, as the land, fertilizers, and energy used to grow biofuel crops could be used to grow food crops instead. Also, in some parts of the world, large areas of natural vegetation and forests have been cut down to grow sugar cane for ethanol and soybeans and palm-oil trees to make biodiesel.
  • Biomass — Renewable Energy from Plants and Animals Source: The National Energy Education Project (Public Domain) Source: The National Energy Education Project (Public Domain) Biomass is organic material made from plants
  • Biomass fuels provided about 4% of the energy used in the United States in 2010. Of this, about 46% was from wood and wood-derived biomass, 43% from biofuels (mainly ethanol),
dpurdy

Directory:Cents Per Kilowatt-Hour - PESWiki - 9 views

  • Method Cents/kW-h Limitations and Externalities WindCurrently supplies approximately 1.4% of the global electricity demand. Wind is considered to be about 30% reliable. 4.0 - 6.0 Cents/kW-h Wind is currently the only cost-effective alternative energy method, but has a number of problems. Wind farms are highly subject to lightning strikes, have high mechanical fatigue failure, are limited in size by hub stress, do not function well, if at all, under conditions of heavy rain, icing conditions or very cold climates, and are noisy and cannot be insulated for sound reduction due to their size and subsequent loss of wind velocity and power. GeothermalCurrently supplies approximately 0.23% of the global electricity demand. Geothermal is considered 90-95% reliable. 4.5 - 30 Cents/kW-h New low temperature conversion of heat to electricity is likely to make geothermal substantially more plausible (more shallow drilling possible) and less expensive. Generally, the bigger the plant, the less the cost and cost also depends upon the depth to be drilled and the temperature at the depth. The higher the temperature, the lower the cost per kwh. Cost may also be affect by where the drilling is to take place as concerns distance from the grid and another factor may be the permeability of the rock. HydroCurrently supplies around 19.9% of the global electricity demand. Hydro is considered to be 60% reliable. 5.1 - 11.3 Cents/kW-h Hydro is currently the only source of renewable energy making substantive contributions to global energy demand. Hydro plants, however, can (obviously) only be built in a limited number of places, and can significantly damage aquatic ecosystems. SolarCurrently supplies approximately 0.8% of the global electricity demand. 15 - 30 Cents/kW-h Solar power has been expensive, but soon is expected to drop to as low as 3.5 cents/kW-h. Once the silicon shortage is remedied through alternative materials, a solar energy revolution is expected.
  • Tide 2 - 5 Cents/kW-h Blue Energy's tidal fence, engineered and ready for implementation, would provide a land bridge (road) while also generating electricity. Environmental impact is low. Tides are highly predictable.
  • Method Cents/kW-h Limitations and Externalities GasCurrently supplies around 15% of the global electricity demand. 3.9 - 4.4 Cents/kW-h Gas-fired plants and generally quicker and less expensive to build than coal or nuclear, but a relatively high percentage of the cost/KWh is derived from the cost of the fuel. Due to the current (and projected future) upwards trend in gas prices, there is uncertainty around the cost / KWh over the lifetime of plants. Gas burns more cleanly than coal, but the gas itself (largely methane) is a potent greenhouse gas. Some energy conversions to calculate your cost of natural gas per kwh. 100 cubic feet (CCF)~ 1 Therm = 100,000 btu ~ 29.3 kwh. CoalCurrently supplies around 38% of the global electricity demand. 4.8 - 5.5 Cents/kW-h Increasingly difficult to build new coal plants in the developed world, due to environmental requirements governing the plants. Growing concern about coal fired plants in the developing world (China, for instance, imposes less environmental overhead, and has large supplies of high sulphur content coal). The supply of coal is plentiful, but the coal generation method is perceived to make a larger contribution to air pollution than the rest of the methods combined.
1 - 20 of 116 Next › Last »
Showing 20 items per page