Out of all Fuel Cells qwhich do you think is the most promising, reliable, and efficient for a future city?

Question

You see our class is doing a project on building a city and well , fuel cells must be used so which fuel cell do you think is most promising, reliable, and efficient for a future city?

Answer 1

This is not the answer you want, but I can see no logical way to power a city from fuel cells. Fuel cells can not be considered a source of energy, because there is no source of free hydrogen on earth.
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This means that energy must be expended to chemically separate hydrogen, and because of some very basic laws of physics, you will never get more energy out of the fuel cell than what you use to separate the hydrogen.
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This makes the fuel cell the equivalent of a battery - and a very inefficient battery at that. Fuel cells make sense in a spacecraft because much energy can be carried in the form of compressed hydrogen. On earth, it makes no sense because you might just as well take the energy you spent making the hydrogen and use it directly.
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So your fuel cell power system does not answer the question of how to power your city. You still need a power source to make the hydrogen for your fuel cells. And if you have a power source, why bother with the fuel cells?
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To answer your question literally, I recommend a Nickel-Metal-Hydride battery. It is not a fuel cell, but it does the same thing - it stores electricity by moving hydrogen between chemical states. And it does so much more efficiently than any other fuel-cell design.

Answer 2

Why must fuel cells be used? are you sponsored by the US gov/global oil companies? no one else thinks fuel cells must be used in cities.

for transport solutions current battery trchnology eg nano technology Li-ion is far more efficeient than any proposed fuel cells because of the inefficiencies of hydrogen distribution (the small molecuels take up a lot of space and escape easily)

for home electric fuel cells are extreemly inefficient compared to large generators and grid distribution systems; the only possible need for fuel cells is to enable nuclear power stations to produce, and sell, hydrogen at night because nuclear generators can't adapt to demand cycles. It is far more efficient to invest in better lighting and appliances.
eg heat pumps for air conditioning or heating.

basially the problem is not the fuel cells but the supporting infrastructure and mind-set, and there are other better solutions which are more technically promising without locking us into the global industrial growth model.

Answer 3

It is important to note that not all fuel cells run on pure hydrogen. Some run on methanol and others on synthetic gases. Up until recently, the large-scale, stationary fuel cell systems have used phosphoric acid fuel cell technology.

Recently, though, other types of large-scale fuel cell technology such as molten carbonate fuel cells, proton exchange membrane fuel cells (what most people think of as ‘hydrogen fuel cells’) and solid oxide fuel cells have taken away market share. Out of this list, the most promising is probably the molten carbonate fuel cells, which can attain 60-percent efficiency, compared to 25 to 40-percent for other methods.