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how long has biofuels been around - Google Search - 0 views

www.google.com/search history biofuel
shared by greenhan99 on 11 Mar 13 - No Cached
  • Biofuels have been around as long as cars have. At the start of the 20th century
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Group items matching "fuel cell" in title, tags, annotations or url - qmstech2 | Diigo ... - 1 views

groups.diigo.com/...search fuel cell fuel cell current
shared by boothreb99 on 11 Mar 13 - No Cached
  • boothreb99 on 11 Mar 13
     
    "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."
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Geothermal Technologies Office: A History of Geothermal Energy in the United States - 0 views

www1.eere.energy.gov/...history.html geothermal history
shared by deepat00 on 12 Mar 13 - No Cached
  • Archaeological evidence shows that the first human use of geothermal resources in North America occurred more than 10,000 years ago with the settlement of Paleo-Indians at hot springs
  • knightoli99 on 12 Mar 13
     
    "Archaeological evidence shows that the first human use of geothermal resources in North America occurred more than 10,000 years ago with the settlement of Paleo-Indians at hot springs. The springs served as a source of warmth and cleansing, their minerals as a source of healing. While people still soak in shallow pools heated by the earth, engineers are developing technologies that will allow us to probe more than 10 miles below the earth's surface in search of geothermal energy. We invite you to study the timeline of the recent history of geothermal energy in the United States."
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Ancient Egyptians built places to live that allowed stored energy from the sun during t... - 0 views

www.diigo.com/...g solar history roman ancient energy sun heat heated convert
shared by hayespay99 on 12 Mar 13 - No Cached
  • Ancient Egyptians built places to live that allowed stored energy from the sun during the day, and a heat release during the night. This kind of architecture heated homes at night while keeping the temperature low during the day. Egyptians also used the sun as part of their mummification process, using the sun to dry dead bodies. The Egyptians used a form of passive solar power. 3rd Century B.C., Greek soldiers with the help of Archimedes, focused light on a Roman fleet by using mirrors,
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EnergyBC: Tidal Power - 2 views

www.energybc.ca/...tidal.html tide form convert history
shared by dpurdy on 12 Mar 13 - No Cached
  • his is somewhat balanced out by long plant lives of 100 years for the actual barrage structure, and 40 for the equipment, as well as low operating costs.
  • An estimate is given by researcher Eleanor Denny. Denny estimates that in order for a facility to be profitable, its capital cost should be less than €530,000 (~$700,000 USD) per MegaWatt which with the current technology is not a realistic goal, meaning that so far the industry produces negative net benefits.50
  • Canada's Race Rocks site, where a single turbine generator converts 65 kW of energy, cost $4,000,000.54 This figure was met with $3,000,000 investment from project partner EnCana's Environmental Innovation Fund, and a grant of just under $1 million awarded to Pearson College and their partners in the project.
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  • This plant produces about 100 times the power generated at Race Rocks. An investment of around €8.5 million ($11 million USD) made SeaGen a reality.
  • The environmental impacts of tidal barrage include hampered fish migration, forced water level changes on the basin behind the barrage, reduced salinity in the basin due to low quantities of ocean water, and reduced ability of currents to transport and suspend sediments
  • sustainable energy resources produce limited amounts of carbon dioxide emissions
  • , they are, by nature, reliant on the natural environment and therefore are vulnerable to the effects of climate change
  • Brief History of Tidal Power The energy stored in tides been known to people for many centuries. The earliest records of tidal mills are dated back to the 8th Century CE.7 The tidal mills were mainly used for grain grinding and were of similar design to the conventional water mills with the exception of the addition of a dam and reservoir. The industrial revolution increased demand for power but tidal energy never got off the ground, undercut by cheap fossil fuels and other developments which offered easier access to power generation. Existing tidal mills became as obsolescent as pre-industrial water-mills. The first large scale modern tidal electric plant started to operate in La Rance Estuary, St. Malo, France in the 1960s and has been operating ever since. In recent years the search for renewable, non-polluting energy sources and the increase in fossil fuel prices has encouraged renewed interest in tidal power.
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My Library for wind - 0 views

www.diigo.com/my sustainable wind
shared by jack wells on 12 Mar 13 - No Cached
  • 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.
  • jack wells on 12 Mar 13
     
    "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."
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tidal energy steps to electricity - Google Search - 1 views

www.google.com/webhp history tide
shared by butlerlei98 on 11 Mar 13 - No Cached
  • butlerlei98 on 11 Mar 13
     
    "Mills using tidal power can be dated back to 12th century Europe, a technology that followed colonists to the Americas."
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Group items matching "history geothermal" in title, tags, annotations or url - qmstech2... - 0 views

groups.diigo.com/...search
shared by jurektho99 on 22 Oct 12 - No Cached
  • The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity. Geothermal energy is a renewable energy source because the heat is continuously produced inside the Earth. ... Cancel
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Research Report: what are the best uses for solar power - 1 views

ultimate-research-assistant.com/ResearchReport.asp use
shared by troisichr99 on 22 Oct 12 - No Cached
  • A quick search on TreeHugger shows that ' solar power ' most often occurs in connection with producing electricity and only secondarily in connection with solar water heaters
  • Compared to electrically heated Water , Solar Water Heating is 57% of the internal rate of return, the scientists found
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Group items matching "hydrogen potential" in title, tags, annotations or url - qmstech2... - 0 views

groups.diigo.com/...search fuel cells potential
shared by carrowluk99 on 24 Oct 12 - No Cached
  • carrowluk99 on 24 Oct 12
     
    if we fix our problems with price and how we make it hydrogen, we have the potential to generate all of our electrical need using fuel cells 
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Group items matching "change future" in title, tags, annotations or url - qmstech2 | Di... - 0 views

groups.diigo.com/...search biofuel future change
shared by filionmar99 on 24 Oct 12 - No Cached
  • We are working to produce biofuels that are low cost, low carbon, sustainable and able to fulfil the world’s transportation fuel needs on a large scale without compromising food production
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Group items matching "fuel cells potential" in title, tags, annotations or url - qmstec... - 0 views

groups.diigo.com/...search fuel cells location
shared by carrowluk99 on 23 Oct 12 - No Cached
  • carrowluk99 on 23 Oct 12
     
    because there is no source, hydrogen is not limited by its location
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A Basic Overview of Fuel Cell Technology - 0 views

americanhistory.si.edu/...basics.htm fuel cell convert
shared by labrumbra99 on 15 Mar 12 - Cached
  • 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.
  • ...6 more annotations...
  • 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
  • labrumbra99 on 08 Mar 13
     
    "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."
  • ricciardellinick on 11 Mar 13
     
    "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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Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biof... - 0 views

www.pnas.org/...11206.short biofuels costs benefits biodiesel ethanol environmental
shared by tillmanash98 on 15 Mar 12 - No Cached
  • Negative environmental consequences of fossil fuels and concerns about petroleum supplies have spurred the search for renewable transportation biofuels.
  • To be a viable alternative, a biofuel should provide a net energy gain, have environmental benefits, be economically competitive, and be producible in large quantities without reducing food supplies.
  • Ethanol yields 25% more energy than the energy invested in its production, whereas biodiesel yields 93% more. Compared with ethanol, biodiesel releases just 1.0%, 8.3%, and 13% of the agricultural nitrogen, phosphorus, and pesticide pollutants, respectively, per net energy gain. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12% by the production and combustion of ethanol and 41% by biodiesel. Biodiesel also releases less air pollutants per net energy gain than ethanol.
  • ...3 more annotations...
  • Even dedicating all U.S. corn and soybean production to biofuels would meet only 12% of gasoline demand and 6% of diesel demand. Until recent increases in petroleum prices, high production costs made biofuels unprofitable without subsidies. Biodiesel provides sufficient environmental advantages to merit subsidy. Transportation biofuels such as synfuel hydrocarbons or cellulosic ethanol, if produced from low-input biomass grown on agriculturally marginal land or from waste biomass, could provide much greater supplies and environmental benefits than food-based biofuels.
  • We use these criteria to evaluate, through life-cycle accounting, ethanol from corn grain and biodiesel from soybeans.
  • These advantages of biodiesel over ethanol come from lower agricultural inputs and more efficient conversion of feedstocks to fuel. Neither biofuel can replace much petroleum without impacting food supplies.
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