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ALTERNATIVE SOUCE OF ENERGY
Alternative souce of energy are derived from sources that donot use upnatural resources and donot harm the environment.
There are no.of alternative source of energywhich damage to the environment caused by the fossil fuels.Today most of the energy is provided through the fossil fuel such as coal & gasoline but because of their diminishing reserves,high prices & most important their damaging effect on the environment,the alternative source of energy is being develop.
For the protection of the environment there are different alternative source of energy :
Alternative Sources of Energy in an Energy Conservation and is owned by Laurence O'Sullivan.
ABOUT THE FUEL CELL
As we know that prduction of electricity by thermal plants is not a efficient method for proper production as it cause pollution. In this type of plants the chemical energy of the fossil fuels is first used for converting water into high pressure steam and then used to run a turbine to produce electricity .Galvanic cell helps us to convert chemical energy into electricity and it is highly efficient.The galvanic cell are design directly to convert energy of combution of fuel like hydrogen ,methane ,methanol etc .into electrical energy .These are known as Fuell cells.
Fuel cells use a chemical reaction, rather than combustion ,to produce electricity in a process that is the reverse process of electrolysis. In the electrolysis process & electric current applied to water & produces hydrogen & oxygen by reversing this process hydrogen & water are combine in the fuel cell to produce electricity and water.
TYPES OF FUEL CELL
Fuel cells are now being treated as a family of technologies which contains five primary types, based on the type of "electrolyte" which is used. Each has the specific characteristics that may make it better for some applications than the others.
Polymer Electrolyte Fuel Cell (PEFC) or Proton Exchange Membrane Fuel Cell (PEMFC) - The electrolyte in this type of fuel cell is an ion exchange membrane made of some type of polymer that is a good conductor of protons. This type of fuel cell runs at low temperatures (usually around 80-degrees Celsius), with electrical efficiencies of about 45%, and it is use as the primary candidate for automotive, small stationary, and portable power applications. PEMFCs require very pure hydrogen as the fuel.
Phosphoric Acid Fuel Cell (PAFC) - The electrolyte in this type of fuel cell is phosphoric acid, & it is concentrated to 100%. PAFCs have an operating temperature of about 100-220 degrees Celsius, with an electrical efficiency of about 37-42%. Buses and stationary applications are currently use PAFCs.
Molten Carbonate Fuel Cell (MCFC) - The electrolyte in this type of fuel cell is usually a combination of alkali carbonates, retained in a ceramic matrix. The MCFC operates temperature at 600-700 degrees Celsius. The high temperature enables the end user to utilize both the electricity and the thermal energy which is generated by the fuel cell, resulting in the electrical efficiencies of more than 70 percent. MCFCs are well-suited to large-scale stationary applications, and are currently being demonstrated for powering buildings. High-temperature fuel cells can more easily be use a wide range of fuels without using a "fuel reformer."
Solid Oxide Fuel Cell (SOFC) - The electrolyte in the SOFC is a solid, nonporous metal oxide. At the temperatures over 650 degrees Celsius, the SOFC can utilize a hydrocarbon fuel directly, without reforming, similar to the MCFC. Also similar to the MCFC, the SOFC generates both electricity and usable thermal energy. High-temperature SOFCs are being demonstrated for stationary power applications, while low-temperature SOFCs are also used for automotive applications.
Alkaline Fuel Cell (AFC) - This was one of the first modern fuel cells to be developed, and was used to provide on-board electric power for the Apollo space vehicle. The electrolyte in this fuel cell is Alkaline (KOH). AFCs require pure hydrogen and pure oxygen as the reactants. The operating temperature for this type of fuel cell is around 200 degrees Celsius.
Other Types of Fuel Cells - There are other types of fuel cells that are relatively newer to the family of fuel cells. The Direct Methanol Fuel Cell (DMFC) is very similar to the PEMFC, but it is able to directly utilize liquid methanol at the anode. There is also a Regenerative Fuel Cell, which contains a membrane that can both electrolyze water into hydrogen and oxygen and, with the flick of a switch, recombine the two elements, producing electricity and water. In a Metal Air Fuel Cell, zinc pellets and an alkaline electrolyte are circulated through the fuel cell stack and are combined with oxygen from air to create electricity, heat and zinc oxide (in a solution of potassium zincate). The zincate can be regenerated in a separate process into fresh zinc pellets.
Fuel cell technologies have the power to change the way we make and use energy. As a power technology, they provide a unique combination of features and benefits:
1>Fuel cells are 2-3 times as efficient as internal combustion engines for the vehicle propulsion.
2> Fuel cell power plants can achieve energy efficiencies over the 80 percent.
1> South Coast Air Quality Management District found that a fuel cell power plant running on natural gas and emits 98% lessnitrogen oxide than the District's own tough standard .
2> Fuel cells can take the automobile out of the climate change debate.
3> Fuel cell power plants are so clean, some cities have exempted the technology from air which permits the requirements.
4> A program to install eight fuel cells at wastewater treatment plants around New York City expects to eliminate nearly 170 tons of regulated emissions and more than 9,000 tons of carbon dioxide, and reduce fuel oil consumption by 3,000 barrels a year.
5> Able to use domestically-produced fuels.
Fewer Moving Parts
1>Don't worry about losing power during electrical storms.
2>High quality power for businesses that lose millions of dollars per hour when the power goes out.
3>Make the grid your backup.
HYDROGEN FUEL CELL
Hydrogen is the most abundant element in the universe and the lightest gas to be known. It is colorless,odourless, tasteless, and nontoxic at room temperature and pressure.
Hydrogen can link today's fossil-based energy supply with the renewable energy of tomorrow..Hydrogen contains more useful energy per pound than any other fuel. This means hydrogen is more efficient on a weight basis than any of the fuels currently used in air or ground transportation.
The main organs of a fuel cell are the negatively and positively charged electrodes, referred to as the anode and cathode. Hydrogen comes into the fuel cell and travels to the anode - -where it is split by the catalyst into protons and electrons. Each molecule of hydrogen has two hydrogen atoms, and the reaction at the anode creates two positive hydrogen ions and two electrons.
The positive hydrogen ions then travel to the cathode through an ion-conductive membrane , where they mix with oxygen atoms. This reaction at the cathode creates the product water.
The water that is produced at the cathode must be removed continuously to avoid lowering the cell efficency. Electrons are carried away along the wires leading to the electrodes to whatever device needs power.
Hydrogen (fuel) is fed into the anode of the fuel cell. Oxygen (from air) is fed into the cathode side. Encouraged by a catalyst, electrons are stripped from the hydrogen atom. Freed of the electrons, the protons pass through the electrolyte, while the electrons are forced to take a different path to the cathode. As the electrons travel their separate path, they create an electric current that can be utilized. At the cathode, another catalyst rejoins the hydrogen atom, which then combines with the oxygen to create a molecule of water.
Use of Hydrogen Fuel Cells to provide power for homes and automobiles will help reduce pollution and fuel costs. There is ongoing research towards reducing the costs associated with Hydrogen Fuel Cells and making the cells more reliable and sustainable. More effort should be placed on investigation and development of Hydrogen Fuel Cell technology in order to improve the quality and cost of living throughout our society. While the cost benefits alone have made Hydrogen Fuel Cells appealing for many people, the health benefits also provide significant incentive for furthering this technology.
FUEL CELL APPLICATION
Fuel cells are obviously used to make electricity, but due to the way they are displayed and discussed in the media, it would be easy to assume that the only use for fuel cells is in cars. But there are actually four main categories -- all of which cover a broad range of uses.
First, there is the transportation application -- which takes the place of internal combustion engines. Many concept cars have already been produced to illustrate how they would work, and some are now going into production. However, fuel cells of the future will also be able to be used in trains, boats, aircrafts, homes and businesses.
Second, there is stationary power applications - which produce electricity in the same way as any other types of power station do. They are easy and cheap to build compared with current methods of producing power -- and would provide an attractive alternative to powering places that the grid doesn' t reach.
There are some remote locations - such as farms, lighthouses and underground complexes that could rely on the use of fuel cells. There's also the possibility for them to be used to supply industrial states or university campuses without the need to be connected to the grid -- so the establishment can regulate and control its own power supply.
Backup power is one of the places where we need advances -- and fuel cells provide the solution. A coal-fired power station can take several hours to get up to speed. Fuel cells have quick start-up -- so whether they' re backing up entire power stations or individual devices -- they will be able to help keep constant power, provided they've got constant fuel.
Finally, they can be used as portable power sources. Battery technology is adequate, but by no means perfect. For the average technological person, laptops, cell phones and MP3 players running out of battery power after just a couple of hours of use is one of the most annoying things possible. Fuel cells, however, can be made to be very similar to normal batteries -- but much longer lasting -- solving one of our current energy problems.
This article has just touched on the possible uses for fuel cells, but as you can see --- they have the potential to entirely take over from current methods of producing energy, and run the planet single-handedly. All we now need is individuals to continue to develop fuels cells, and aid with the transition to the hydrogen economy.
Fuel cells can provide electricity in an almost unlimited number of applications thanks to their modularity - you can build a fuel cell to provide as much power as you need, depending on the application. Fuel cells can provide long run-time power to your cellular telephone, or provide power for the bus you take to work, or the building you work in.
Fact Sheets on Fuel Cell Applications:
- Industrial/Commercial Power Applications
- Residential/Small Commercial Power Applications
- Transportation Applications
- Portable Power Applications
- Fuel Cell Components
The most commonly used fuel cell stack components and materials include:
-Proton conductive membrane
- Gas diffusion layers
- Catalyst layers
- Bipolar plates
- End plates
RESULT & SUMMARY
From the above discussion we conclude that the production of eletricity by thermal plants is not a efficient method for proper production as it cause pollution as it happens only in early times.But now a days galvanic cell helps us to convert chemical energy into electricity and it is highly efficient.As the fuel cell uses a chemical reaction to produce electricity.There it has been also discussed different types of fuel cell.
- Polymer Electrolyte Fuel Cell (PEFC) or Proton Exchange Membrane Fuel Cell (PEMFC)
- Phosphoric Acid Fuel Cell (PAFC)
- Molten Carbonate Fuel Cell (MCFC)
- Solid Oxide Fuel Cell (SOFC)
- Alkaline Fuel Cell (AFC)
- Other Types of Fuel Cells
Their benefits and about the hydrogen fuel cell.As we know that hydrogen is the most abundant element in the universe and the lightest gas to be known.There has been also disscussed about the working of hydrogen fuel cell and also their application & component.