Water-Powered Cars: Hydrogen Electrolyzer Mod Can’t Up MPGs

After batting down the hype over startups and DIYers claiming they could run a car on water, PM’s senior automotive editor installs a hand-built HHO kit


Unfortunately, I have to indict their physics. The entire concept of running your car on water is based on bad science. The idea is to use electricity from the car’s alternator to electrolyze water into HHO, a mixture of pure hydrogen and oxygen. This mix is fed into the intake air, where it is burned along with gasoline, thereby increasing your fuel economy anywhere from 15 to 100 percent