What is a Fuel Cell? What are its advantages and its Disadvantages?
A fuel cell is an electrochemical energy conversion device that converts hydrogen and oxygen into electricity, heat, and water. It is very much like a battery that can produce electricity while being recharged continuously.
Advantages of Fuel Cells
Basic fuel cells running on pure hydrogen are pollution free, giving off only electricity, water, and heat. The potential for fuel cells to provide zero or near-zero emissions has been a significant force in the development of the technology over the past 30 years, and is drawing increasing attention to the technology today.
* 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) in a complete fuel cell unit are relatively mature and simple technologies that should prove extremely reliable.
* Unlike batteries that must be disposed of once their chemicals are used up, fuel cell reactions do not degrade over time and can theoretically provide continuous electricity.
* Traditional power plants must be large in order to gain efficiency, but fuel cells can achieve higher efficiencies at any scale, making them perfect for small portable, residential, and transportation uses.
* Because fuel cells are clean and efficient at any size, they can be located almost anywhere, including dense urban areas where both air quality and transmission congestion may be of concern. Fuel cells can offer an alternative to building new power lines, while also reducing American dependence on foreign oil. Fuel cells can provide more reliable power wherever electricity is needed, making the whole electric power grid more robust and reliable. Distributed application of small fuel cells will also enhance security of key infrastructures, such as our communication and water systems.
* Economically, fuel cells represent a prudent path to provide the country's electric power because they can be installed quickly, are fuel flexible, and can be put in place incrementally, mitigating the need for more costly and sweeping changes.
Disadvantages of Fuel Cells
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.
Currently, there is no hydrogen infrastructure to supply coast-to-coast delivery of hydrogen fuel. Technologies are being developed to provide alternative fuel storage and delivery methods. SOFCs, MCFCs and PAFCs can internally reform natural gas, providing the perfect solution for industrial use but MCFCs and PAFCs are too large for home and transportation use and SOFCs still have years in development. PEMs and AFCs can use fuel reformers to convert hydrocarbons, such as gasoline and natural gas, into hydrogen, but this technology can lower the overall efficiency of the fuel cell by 1/4 and can release small amounts of pollutants. Onboard fuel storage and conversion solutions are being developed but they are still years from being perfected.