Why do we need Fuel Cells?

Usually, society's power come from fossil fuels, which have many disadvantages: production of pollutants in large quantities, limited availability and being the cause of conflicts around the world. Fuel cells have the ability to power cellphones, cars and even houses. Their advantages are specially important for applications that are energy limited. A good example is the power for portable devices, which is limited and needs constant recharging.

Studies have shown that fuel cell systems are capable of providing the same amount of energy as batteries with a smaller system weight and volume, which is a great advantage for portable power systems. Future markets for the fuel cells could be the transportation, portable and stationary sectors. Each market could make use of fuel cells for different reasons.

The portable sector needs fuel cells to power devices for longer periods of time. Convergence of devices is the current trend in electronics, and the amount of power required is the limiting factor. To allow devices run for longer periods of time would foment the development of new, multi-functional equipment. The military is specially interested in fuel cells since they sorely need to increase the amount of time their devices can run before they need to be recharged. Also, for the military, the advantages also include the greater power, lesser weight, less or no noise and lower heat generation.

The transportation market has been looking for alternatives to fossil fuel, since their sources will, one day, end and legislation from different countries are progressing towards further protection of the environment. Some fuel cell types, like the PEM, release only water vapor during working conditions, thus being an alternative for environment-friendly vehicles.

The stationary sector can benefit from the physical versatility of fuel cells, since they can power houses or businesses. These fuel cells are specially important for generators, when more conventional electricity sources aren't available. The end result of this advantage is that money can be saved when power goes down for short periods of time.

Source:

SPIEGEL, Colleen. PEM Fuel Cell Modeling and Simulation Using MATLAB^®. Burlington, MA, USA: Academic Press, 2008. 440 p.

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