[ngreen]

Cool.

I think $140 sounds reasonable. I am on the Chemical Engineering Car team and the fuel cell car kits were prevalent at competition a couple of years ago. Since then they've made them illegal because they can be ran nearly unmodified, and make the competition unfair to those with completely team built cars. A few team still run fuel cell, but they manufacture them themselves (including the proton exchange membrane). The team that won nationals this year, Puerto Rico Mayaguez, built a fuel cell for their car.

To be dangerous, the hydrogen would need to be at proper concentration between the LFL and UFL, and require an ignition source. With proper precautions this shouldn't be a problem. I haven't seen problems with hydrogen at our competition, however, the green machine competition uses larger tanks and more hydrogen than the chemEcar.

On another safety note: Last year at nationals a car exploded during its run. It was using a chemical reaction to generate pressure and using PVC as a pressure containing device. Bad idea. Luckily, this year major rule changes required proper pressure containing devices, gauges, check valves, and proof your car won't blow up when you put it on the line.

edit: $140 is reasonable, albeit high, for the car type kits (experiment kits). For the fuel cells they are using it would be higher.