OK, I understand that we all want a zero-emissions car, but this is getting out of hand. Just this past weekend a woman called up the Car Talk guys to ask if her husband was crazy for trying to modify the family SUV into a water-powered car. Coincidentally, veteran technology query-artist Sam and her boyfriend sent me a note a few weeks ago with a YouTube video they’d found of a newscast interviewing the inventor of just such a car. To their credit, Sam, her man, and the Car Talk caller were extremely skeptical about this seeming solution to our energy and global-warming crises. And with good reason, as it turns out (for the record, a Wikipedia entry debunks the water-fueled car, too, but I thought it a bit dense).
OK, we’ll start with what the water-powered car advocates claims it will do: Generate energy from water. How? First, electrolyze the water. That will split the water into its component elements, namely, hydrogen and oxygen. Then pump that H2 and O2 mixture (known to the Car Talk caller’s husband as “hydroxy” and the fellow in the video as “H-O-H”, but we’ll stick with the common names) over to the engine. Now burn the gasses to move the pistons and thus move the car. The waste product will be water, once again (O2 + 2H2 —–> 2H2O). Water in, water out. Perfect!
Of course, Oyster’s Garter readers are all smarty-pantses (Bet you didn’t know the plural of that word. We’re a full-service operation here at TOG.), so you’re wondering about step 1, with the electrolyzing of the water. “Where does the electricity come from?” I hear you asking. Sadly, that’s the downfall of the water-powered car. The electricity comes from the battery, of course. And where does the battery get its energy? Why, from the battery factory, of course. Well, water-powered car advocates will argue that the battery is recharged from the alternator with the normal running of the car, just like any car battery. But it takes far more energy from the battery to split the water atoms then you get back from burning the component gases (water is very stable and its bonds prefer not to break), so there’s a substantial net loss.
Ultimately, the water-powered car is not actually water-powered at all. It’s battery powered, but very inefficiently battery powered. Of course, given our current experience with fueling our cars from food, maybe it’s for the best that we don’t fuel them with water.
I’ll close with this wonderfully understated line from the Wikipedia entry:
It is theoretically possible to extract energy from water by nuclear fusion, but fusion power plants of any scale remain impractical, much less on an automotive platform.