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streetscor99

Fuel cells, what is a fuel cell, disadvantages, benefits - 0 views

  • * Because there is no combustion in a fuel cell, fuel is converted to electricity more efficiently than any other electrical generating technology available today. * There are no moving parts in a fuel cell stack, making them more reliable and quieter than generators. Even the ancillary systems (fans, pumps, controls, etcetera) in a complete fuel cell unit are relatively mature and simple technologies that should prove extremely reliable.
  • In the past, fuel cells were large and extremely expensive to manufacture, just as the first calculators and computers were. But, just like these products, the cost of fuel cells will quickly come down to consumer-affordable levels with mass production. We are currently in a transition period now, where many fuel cell companies are investing literally hundreds of millions of dollars to gear up for mass manufacturing at the same time they are trying to begin to develop a variety of markets for their product.
boothreb99

Group items matching "fuel cell" in title, tags, annotations or url - qmstech2 | Diigo ... - 1 views

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    "The fuel cell is being considered as an eventual replacement for the internal combustion engine for cars, trucks and buses. Major car manufacturers have teamed up with fuel cell research centers or are doing their own development. There are plans for mass-producing cars running on fuel cells. Because of the low operating cost of the combustion engine, and some unresolved technical challenges of the fuel cell, however, experts predict that a large scale implementation of the fuel cell to power cars will not occur before 2015, or even 2020."
hardingmar00

Geothermal energy in the United States - Wikipedia, the free encyclopedia - 0 views

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    "eothermal energy in the United States continues to be an area of considerable activity. In 2012, the United States led the world in geothermal electricity production with 3,386 megawatts (MW) of installed capacity;[1][2] the largest group of geothermal power plants in the world is located at The Geysers, a geothermal field in California.[3] The United States generates an average of 15 billion kilowatt hours of geothermal power per year, comparable to burning some 25 million barrels (4,000,000 m3) of oil or 6 million short tons of coal per year.[4] Geothermal power plants are largely concentrated in the western states. They are the fourth largest source of renewable electricity, after hydroelectricity, biomass, and wind power. A geothermal resource assessment shows that nine western states together have the potential to provide over 20 percent of national electricity needs.[4][5]"
mchughkon99

Tidal Power - 0 views

  • Although this source of energy shows some promise in terms of "clean", renewable energy there have been some roadblocks to widespread use of energy from the tides. This type of energy should not be put on the back burner even though there appears to be limited opportunities at this time
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    can be cost effective
carusonepay99

Wind energy FAQ | EWEA - 0 views

  • Each year we release millions of tonnes of carbon dioxide by burning fossil fuels (oil, coal and gas). In 2010, on average, every single EU citizen emitted 9.4 tonnes of CO2 – that’s enough to fill ten three-storey buildings. For every kWh of wind energy that you use, you will save approximately 696g of CO2. EWEA estimates that wind energy avoided the emission of 140 million tonnes of CO2 in 2011 in the EU, equivalent to taking 33% of cars in the EU – 71 million vehicles – off the road. This avoided CO2 costs of around €3.5 billion (assuming a price of €25/t CO2). Choosing how your electricity is produced plays an important role in protecting the climate: it’s easy to switch to a green power provider; you request the change and your current and future providers will organise it themselves.
wellsann99

The Most Frequently Asked Questions about Wind Energy - 0 views

  • In 1997, U.S. power plants emitted 70% of the sulfur dioxide, 34% of carbon dioxide, 33% of nitrogen oxides, 28% of particulate matter and 23% of toxic heavy metals released into our nation's environment, mostly the air. These figures are currently increasing in spite of efforts to roll back air pollution through the federal Clean Air Act.
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    wind power technology
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.
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  • electrical charges of less than $.05 per KWh; which makes it competitive with fossil fuel generators.
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    " 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."
wellsann99

Wind Energy: Facts - 1 views

  • Over 8,500 MW were installed in the US in 2008 (just beating out China with 6,300 MW). This represents: 50 percent increase from 200742 percent of all new generating capacity installed in 2008$17 billion investment44 million tons of carbon emissions avoided (equivalent of 7 million cars)35,000 new jobs
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    wind power today
wellsann99

wind-energy-industry - 0 views

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    wind power in the U.S ending in 2008
lemairenat98

ScienceDirect.com - Renewable Energy - Initial evaluation of tidal stream energy resour... - 0 views

  • Portland Bill (Dorset, UK) is a promising site for tidal stream energy exploitation; it combines high tidal stream velocities around the headland with a location closer to population centres than other proposed sites.
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    "Portland Bill (Dorset, UK) is a promising site for tidal stream energy exploitation; it combines high tidal stream velocities around the headland with a location closer to population centres than other proposed sites."
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
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    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.
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    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.
rainwateremi99

The Cost of Biofuels in Guatemala - Photographs - NYTimes.com - 0 views

  • Now that the United States is using 40 percent of its crop to make biofuel, it is not surprising that tortilla prices have doubled in Guatemala, which imports nearly half of its corn. 
darnleykan99

bniofuels - Google Search - 0 views

shared by darnleykan99 on 12 Mar 13 - No Cached
crandallmad00

How Tidal Power is Riding the Crest of a Wave - 1 views

  • The argument for tidal power is overwhelming: it’s a practically infinite supply of clean energy and has one of the smallest carbon footprints of any power source; it’s reliable, cost-efficient, has minimal effect on the marine environment and virtually zero effect on sea-gazing aesthetics. Most importantly, The World Energy Council estimates that the energy that can be harvested from world’s oceans is equal to twice the electricity that the world produces now
  • A reason many energy experts are looking at what tidal may be able to contribute, compared to other renewable sources like wind power, is that the amount of energy generated from a power-generating turbine is proportional to the density of the fluid that flows back and forth – meaning a water turbine has several hundred times the power of an air turbine.
  • Seawater is denser than air; a lot denser – 832 times to be exact, meaning an 8 knot tidal current has more energy than a 380kph wind. This means a wave farm of ‘sea snakes’ – devices built by Scotland’s Pelamis Wave Power – covering half a square mile of ocean could produce 30 MWh of power, which is estimated to be enough for 20,000 homes. A wave farm covering 472 square miles could supply 24 million households – enough for the entire UK.
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  • Partly this has been due to the uncertainty of how to harness all this abundant marine energy. While it’s great that there’s the potential to harness up to 153 GW of tidal power in the UK alone,
dpurdy

NRDC: American Wind Farms - 2 views

  • Today, wind farms generate about 50,000 megawatts of clean, renewable energy -- the equivalent of the energy produced by 12 Hoover Dams.
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    "Today, wind farms generate about 50,000 megawatts of clean, renewable energy -- the equivalent of the energy produced by 12"
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.
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