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How to Charge Your Cellphone Using Wasted Heat
Ilya writes "Companies such as BMW are investing in Thermoelectric Generators to make their cars more efficient by replacing the alternator. Thermoelectric Generators convert wasted heat from the engine into electrical power. This green instructable shows how you can use the same technology right now at home to harvest expelled heat from home appliances to charge your cellphone and other gadgets. Also features a lego racer powered by the roaring flames of a tea candle."
I read the article in Car & Driver the O.P. is referring to a while ago (if it's not already obvious the automotive company he is referring to is BMW). At least in automotive applications, it begs the question, is it worth the effort? The extra parts, weight, and cost you'd have to add to a vehicle would probably cause you to break even in terms of MPG or dollars per gallon. The situation is similar with diesel engine options, the extra initial cost of the diesel optioned vehicle is often times just not worth it, despite the MPG advantage.
Everything starts somewhere.
512 MB RAM, 20 GB disk, 200 GB transfer, five datacenters. $19.95/month.
It's vastly more efficient, and probably less expensive, to redesign the Dryer/Air Conditioner/whatever to waste less heat in the first place. So I'm not really disagreeing with you, but I feel that it's a bit more of a feel good effort than an actual relevant solution.
Yes, since we can't solve the problem in one step, we should never proceed
To restate your premise:
Given that the average American drives 8500 miles per year, spending one day a month bicycling to work isn't going to make a damn bit of difference.
Additionally, such waste heat might not actually be "free" - depending on some of the implementation details.
The engine works by generating heat and then converting it to mechanical motion while dissipating that heat to a cold sink. If you don't "waste" that heat by sending it to a cold sink then the engine operates less efficiently.
Again, it depends on the details - the energy might be "free," or it might just rob the engine of power just as an alternator does. You can't get around the laws of thermodynamics, though...
P.S. Ever heard of google?
Please, it's a fairly esoteric piece of knowledge and this is as good a forum to ask it in as any. A bit of civility wouldn't kill you.
All intents and purposes. Not intensive purposes.