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New thermoelectric generator converts vehicle exhaust heat into electricity, boosting fuel efficiency
(www.inceptivemind.com)
This is a most excellent place for technology news and articles.
I doubt this will ever become any useful at all. 50 Watts is nothing compared to what the car engine outputs at high speed. Even a small engine has some 35kW, i.e. 35000 Watts.
I could see it maybe being used as an emergency back up alternator, just enough to keep lights on and engine firing (with storage) to get you to safety.
Do alternators fail that often?
Nope. It does suck when they do.