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dpurdy

Fuel Cells - Electrochemical Power - 0 views

www.fuelcell.no/principle_history_eng.htm

history

shared by dpurdy on 03 Nov 11 - No Cached
  • The best known early fuel cell experiments were performed in 1842 by the British physicist and lawyer, Sir William R. Grove (1811-1896)
  • Due to easily accessible and large amounts of oil and the invention of the combustion engine (Carl Friedrich Benz and Gottlieb Daimler), fuel cells were forgotten until the middle of the 20th century. In the US Apollo space programme, fuel cells exhibited their first renaissance in the 1960’s. 
  • Fuel cell development has been slowed down by a fear of hydrogen as a fuel. It is commonly believed that hydrogen is an extremely explosive and dangerous gas. Most of this belief was founded in 1937, when the hydrogen-filled zeppelin “Hindenburg” caught fire and crashed in Lakehurst, USA.
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dpurdy

Historical Overview - 0 views

www.pvresources.com/...historicaloverview.aspx

solar history

shared by dpurdy on 20 Sep 13 - No Cached
  • 90 years ago - in 1921 Albert Einstein was awarded a Nobel Prize for explanation of the PV-effect. 70 years ago - in 1941, the first silicon monocrystalline solar cell was constructed. 60 years ago - in 1951, the first germanium solar cells have been made.
  • 1958, the same company introduced a solar cell with 9 % efficiency. The first radiation-proof silicon solar cell was produced for the purposes of space technology in the same year. On 17th March, the first satellite powered by solar cells, Vanguard I, was launched. The system ran continuously for 8 years.
olearydev99

Fuel Cells are not Pollution Free: Where Will the Water Go? - 0 views

www.roperld.com/...fuelcellspollution.htm

fuel cell pollution

shared by olearydev99 on 12 Mar 13 - No Cached
  • olearydev99 on 12 Mar 13
     
    "When hydrogen combines with oxygen to produce water in a fuel cell the hydrogen is taken from a tank carried in the vehicle and the oxygen is taken from the air (as it is in gasoline-combustion vehicles). The reaction is 2 H2 + O2 -> 2 H2O . So, for every 2 hydrogen atoms taken from the fuel tank, 1 oxygen atom is taken from the air. An oxygen atom is about 16 times more massive than a hydrogen atom, so the water molecule is 9 times [(16 + 2) / 2] more massive than the 2 hydrogen atoms used to make it."
dpurdy

How do Photovoltaics Work? - NASA Science - 1 views

science.nasa.gov/...solarcells

solar history convert

shared by dpurdy on 08 Mar 13 - No Cached
  • Photovoltaics is the direct conversion of light into electricity at the atomic level. Some materials exhibit a property known as the photoelectric effect that causes them to absorb photons of light and release electrons. When these free electrons are captured, an electric current results that can be used as electricity.
  • When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity. This electricity can then be used to power a load, such as a light or a tool.
  • bolendev99 on 08 Mar 13
     
    " Solar cells are made of the same kinds of semiconductor materials, such as silicon, used in the microelectronics industry. For solar cells, a thin semiconductor wafer is specially treated to form an electric field, positive on one side and negative on the other. When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity. This electricity can then be used to power a load, such as a light or a too"
  • dpurdy on 12 Mar 13
     
    "The photoelectric effect was first noted by a French physicist, Edmund Bequerel, in 1839, who found that certain materials would produce small amounts of electric current when exposed to light. In 1905, Albert Einstein described the nature of light and the photoelectric effect on which photovoltaic technology is based, for which he later won a Nobel prize in physics. The first photovoltaic module was built by Bell Laboratories in 1954. It was billed as a solar battery and was mostly just a curiosity as it was too expensive to gain widespread use. In the 1960s, the space industry began to make the first serious use of the technology to provide power aboard spacecraft. Through the space programs, the technology advanced, its reliability was established, and the cost began to decline. During the energy crisis in the 1970s, photovoltaic technology gained recognition as a source of power for non-space applications."
phinneycha99

Energy and kids - 1 views

www.kids.esdb.bg/solar.html

solar how converted

shared by phinneycha99 on 26 Oct 12 - No Cached
  • phinneycha99 on 26 Oct 12
     
    "Photovoltaic cells, like batteries, generate direct current (DC) which is generally used for small loads (electronic equipment).  When DC from photovoltaic cells is used for commercial applications or sold to electric utilities using the electric grid, it must be converted to alternating current (AC) using inverters, solid state devices that convert DC power to AC. "
geczyluk99

Benefits and Challenges - 0 views

www.fueleconomy.gov/...fcv_benefits.shtml

fuel cell co2

shared by geczyluk99 on 22 Oct 12 - No Cached
  • Fuel cell systems are not yet as durable as internal combustion engines, especially in some temperature and humidity ranges.
  • FCVs are currently more expensive than conventional vehicles and hybrids. Manufacturers must bring down production costs, especially the costs of the fuel cell stack and hydrogen storage, to compete with conventional technologies.
  • collignonaut99 on 12 Mar 13
     
    "FCVs are currently more expensive than conventional vehicles and hybrids. Manufacturers must bring down production costs, especially the costs of the fuel cell stack and hydrogen storage, to compete with conventional technologies."
rutaemi98

How Fuel Cells Work | ClearEdge Power - 1 views

www.clearedgepower.com/...how-fuel-cells-work

transported fuel cells

shared by rutaemi98 on 22 Oct 12 - No Cached
  • About the size of a refrigerator, the ClearEdge Plus fuel system hooks up to your natural gas supply and through its fuel processor, draws the hydrogen molecules out. Then, through an electrochemical process that combines the hydrogen molecules with oxygen, the unit generates up to 5kW of electricity for use throughout your entire home and allows you the control to select specific critical circuits you want to remain "up" even when the grid is "down."
giumarraant99

Hydrogen Fuel Cell | Yale Office of Sustainability - 1 views

sustainability.yale.edu/hydrogen2

pollution use how

shared by giumarraant99 on 22 Oct 12 - No Cached
  • At 250 kilowatts, the fuel cell produces 40-50% of the electricity for the Environmental Science Center. Its electricity production alone is 47% effective, and the addition of heat recovery allows for up to 60% efficiency
  • While designed to run on pure hydrogen, Yale’s fuel cell is actually powered by natural gas, 80% of which is usable hydrogen. The fuel cell takes in natural gas and water and produces water, electricity, and hot air.
  • giumarraant99 on 22 Oct 12
     
    Explains what this energy source is best suited for and how this energy source reduces other forms of pollution
brockwaymck99

Reducing the Cost of Fuel Cells - 0 views

oilprice.com/...ng-The-Cost-Of-Fuel-Cells.html

cost hydrogem

shared by brockwaymck99 on 22 Oct 12 - No Cached
  • Most folks don’t realize the depth of the economic problem that fuels cells pose for mass adoption.  Often there are price quotes running in the tens or hundreds of thousands of dollars.  That’s because the catalysts of choice are the noble metals platinum or palladium.  These are very rare metals, more so than gold and have considerable market presence already in the automotive field.
dpurdy

http://ec.europa.eu/research/energy/pdf/hlg_vision_report_en.pdf - 1 views

ec.europa.eu/...hlg_vision_report_en.pdf

hydrogen uses future co2

shared by dpurdy on 26 Oct 12 - No Cached
    • slentzkel99
      slentzkel99 on 26 Oct 12
       
      Report on hydrogen economy potential 
  • dpurdy on 26 Oct 12
     
    Challenges Producing hydrogen in the large quantities necessary for the transport and stationary power markets could become a barrier to progress beyond the initial demonstration phase.  Uses: Fuel cells will be used in a wide range of products, ranging from very small fuel cells in portable devices such as mobile phones and laptops, through mobile applications like cars, delivery vehicles, buses and ships, to heat and power generators in stationary applications in the domestic and industrial sector. Future energy systems will also include improved conventional energy converters running on hydrogen (e.g. internal combustion engines, Stirling engines, and turbines) as well as other energy carriers (e.g. direct heat and electricity from renewable energy, and bio-fuels for transport). 
smithree98

Hydrogen Fuel-Cell Vehicles - Is Hydrogen the Fuel of the Future? - 1 views

environment.about.com/...fcv.htm

hydrogen fuel all benifits

shared by smithree98 on 15 Mar 12 - No Cached
  • The benefits of ditching fossil fuels for hydrogen are many, of course. Burning fossil fuels like coal, natural gas and oil to heat and cool our buildings and run our vehicles takes a heavy toll on the environment, contributing significantly to both local problems such as elevated particulate levels and global ones such as a warming climate. The only by-product of running a hydrogen-powered fuel cell is oxygen and a trickle of water, neither of which will cause any harm to human health or the environment.
  • But right now, 95 percent of the hydrogen available in the United States is either extracted from fossil fuels or made using electrolytic processes powered by fossil fuels, thus negating any real emissions savings or reduction in fossil-fuel usage. Only if renewable energy sources—solar, wind and others—can be harnessed to provide the energy to process hydrogen fuel can the dream of a truly clean hydrogen fuel be realized.
  • They concluded that we’d lower greenhouse gas emissions more by driving gasoline/electric hybrid cars than by driving fuel-cell cars run on hydrogen from coal. Hydrogen made using natural gas would fare a little bit better in terms of pollution output, while making it from wind power would be a slam-dunk for the environment.
  • ...4 more annotations...
  • many reasons, ranging from safety to cost to lack of demand.
  • Another problem is the lack of hydrogen refueling stations
  • replacing the fossil fuels responsible for global warming and various nagging forms of pollution.
  • they are spending upwards of $1 million to produce each one due to the advanced technology involved and low production runs. Toyota hopes to reduce its costs per fuel-cell vehicle to around $50,000 by 2015
  • smithree98 on 22 Oct 12
     
    says most things about hydrogen and what it does
stamperdyl98

Environment « myFC - 0 views

www.myfuelcell.se/...environment

hydrogen environmental

shared by stamperdyl98 on 15 Mar 12 - No Cached
  • Through the use of hydrogen together with fuel cell technology it is possible to achieve a radical decrease in local pollution of carbon dioxide, nitrogen oxides and particles from the transportation sector. Although the production of hydrogen from fossil fuels affects the environment it is an advantage that the carbon dioxide emissions can be separated already on the production site. This becomes evident when hydrogen is used as vehicle fuel, avoiding pollution from every individual vehicle.The only emission from a fuel cell reacting with hydrogen is pure water. The environmental gains are high, provided that pollution in the hydrogen production process is kept low. A fuel cell is approximately twice as energy efficient as a combustion engine if used in a regular car. The effect is that, using the same amount of energy, a fuel cell car can drive twice as far as a car with a combustion engine can.
plattjak98

How Hydrogen Fuels Cells Work - 0 views

inventors.about.com/...Physics_Illustr_2.htm

hydrogen how

shared by plattjak98 on 13 Mar 12 - No Cached
  • The hydrogen fuel cell operates similar to a battery. It has two electrodes, an anode and a cathode, separated by a membrane. Oxygen passes over one electrode and hydrogen over the other. The hydrogen reacts to a catalyst on the electrode anode that converts the hydrogen gas into negatively charged electrons (e-) and positively charged ions (H+).
  • plattjak98 on 13 Mar 12
     
    The hydrogen fuel cell operates similar to a battery. It has two electrodes, an anode and a cathode, separated by a membrane. Oxygen passes over one electrode and hydrogen over the other. The hydrogen reacts to a catalyst on the electrode anode that converts the hydrogen gas into negatively charged electrons (e-) and positively charged ions (H+).
rutaspe99

Hydrogen Power and Fuel Cells - Renewable Energy World - 3 views

www.renewableenergyworld.com/...hydrogen

fuel cell

shared by rutaspe99 on 19 Mar 12 - Cached
  • Hydrogen Energy Hydrogen is the simplest element. An atom of hydrogen consists of only one proton and one electron. It's also the most plentiful element in the universe. Despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on the Earth - it's always combined with other elements. Water, for example, is a combination of hydrogen and oxygen (H2O).
  • Hydrogen Energy Hydrogen is the simplest element. An atom of hydrogen consists of only one proton and one electron. It's also the most plentiful element in the universe. Despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on the Earth - it's always combined with other elements. Water, for example, is a combination of hydrogen and oxygen (H2O). Hy
  • Hydrogen is also found in many organic compounds, notably the hydrocarbons that make up many of our fuels, such as gasoline, natural gas, methanol, and propane.
  • slentzkel99 on 22 Oct 12
     
    Hydrogen is also found in many organic compounds, notably the hydrocarbons that make up many of our fuels, such as gasoline, natural gas, methanol, and propane.
  • rutaspe99 on 12 Mar 13
     
    A fuel cell combines hydrogen and oxygen to produce electricity, heat, and water. 
smithree98

Fuel Cell Advantages and Disadvantages - 1 views

www.futurecars.com/...hydrogen_fuellcell_cars2.html

hydrogen fuel benefit advantages disadvantages cell

shared by smithree98 on 19 Mar 12 - No Cached
  • Conceptually, replacing the current oil-based infrastructure with hydrogen would cost billions, maybe trillions, of dollars. Although abundant in the universe, hydrogen is fairly rare in our atmosphere, meaning that it has to be extracted (for example through electrolysis, as explained above) and currently, the process is cost prohibitive and inefficient. Its production at energy plants creates excessive carbon dioxide. When it burns, a hydrogen flame is virtually invisible; coupled with the gas’s propensity for escaping, in small amounts, almost any tank, there are concerns about explosions. On the plus side, hydrogen is so light it typically is dispersed in the air very quickly. On-board storage is a major issue; a hydrogen tank would currently be too large for a car. It is a very flammable gas (think of the Hindenburg), which further adds to the on-board storage problems.
  • smithree98 on 24 Oct 12
     
    advantages and disadvantages of hydrogen fuel cells
dpurdy

Fuel Cells - Electrochemical Power - 0 views

www.fuelcell.no/principle_mainpage_eng.htm

hydrogen how

shared by dpurdy on 03 Nov 11 - No Cached
  • Fuel Cell Principle A fuel cell is an electrochemical energy converter. It converts chemical energy into electrical energy by two separated electrochemical reactions. In a hydrogen-fuelled polymer electrolyte membrane fuel cell (PEMFC), hydrogen is oxidised to protons and electrons at the anode. Protons migrate through the membrane electrolyte to the cathode. As the membrane is an electric insulator, electrons are forced to flow in an external electric circuit. At the cathode, oxygen reacts with protons to produce water, which is the only waste product
dpurdy

HowStuffWorks "How Fuel Cells Work" - 0 views

auto.howstuffworks.com/...fuel-cell5.htm

Hydrogen cost infrastructure

shared by dpurdy on 03 Nov 11 - Cached
  • CostChief among the problems associated with fuel cells is how expensive they are. Many of the component pieces of a fuel cell are costly.
  • InfrastructureIn order for PEMFC vehicles to become a viable alternative for consumers, there must be a hydrogen generation and delivery infrastructure. This infrastructure might include pipelines, truck transport, fueling stations and hydrogen generation plants
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charlesjos00

Definition of a Solar Cell - History of Solar Cells - 0 views

inventors.about.com/...solar_cell.htm

solar

shared by charlesjos00 on 26 Sep 13 - Cached
  • A solar cell is any device that directly converts the energy in light into electrical energy through the process of photovoltaics. The development of solar cell technology begins with the 1839 research of French physicist Antoine-César Becquerel. Becquerel observed the photovoltaic effect while experimenting with a solid electrode in an electrolyte solution when he saw a voltage develope when light fell upon the electrode.
dylan purner

HowStuffWorks "Photovolatic Cells: Converting Photons to Electrons" - 0 views

science.howstuffworks.com/...solar-cell1.htm

convert solar

shared by dylan purner on 24 Sep 13 - No Cached
  • Photovoltaic cells are made of special materials called semiconductors such as silicon, which is currently used most commonly. Basically, when light strikes the cell, a certain portion of it is absorbed within the semiconductor material. This means that the energy of the absorbed light is transferred to the semiconductor. The energy knocks electrons loose, allowing them to flow freely.
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