AC Propulsion had a Power Point slide where they compared the efficiency
of various "fuels". Their standard was an EV with the equivalent of 50
MPG. A similar vehicle, powered by hydrogen produced from reformatted
natural gas and fed into a fuel cell, was the equivalent of 30 mpg while
hydrogen produced by electrolysis was the equivalent of 12 mpg.
There a number of technical problems with fuel cells:
1) A fuel cell life expectancy was about 2,000 hours. Since my average
driving speed is 30 mpg, I would have to replace my fuel cell every 60K
miles. Therefore, a different fuel cell construction technique would
have to be used.
2) A pack of battery or electrolytic capacitors or an ICE was needed to
aid in acceleration. Therefore, a faster way of transferring the
"proton" through the electrolyte is needed. Think of a proton as a
person needed to run through air as opposed through water or molasses.
3) The storage of hydrogen to go 300 miles in a Toyota Camry needed 3
specially carbon wound tanks where the internal pressures reached 700
bar. A bar is 14.7 pounds per square inch. This equates to 5 tons per
square inch in a "2 ton" vehicle. Catastrophic failures would be
catastrophic. The hydrogen, therefore, needs to be stored in a
molecular sponge where the hydrogen freely flows in and out of storage
without much energy inducements. One real scheme required 800 degree
Fahrenheit temperatures to release the hydrogen from storage.
Given the number of technical problems that need to be solved, I don't
see hydrogen fuel celled vehicles coming into common use anytime soon.
_______________________________________________
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
http://lists.evdl.org/listinfo.cgi/ev-evdl.org
For EV drag racing discussion, please use NEDRA
(http://groups.yahoo.com/group/NEDRA)
