How's this for a tantalizing possibility: rather than install solar panels on your roof, the lost heat from your furnace could power your home.
That's not yet a product, but a growing number of scientists and clean-tech companies are trying to coax usable energy from smokestacks and other waste-heat sources.
A global push toward energy efficiency is prodding more industrial outfits to reuse heat from their operations that would otherwise be lost to the skies.
Meanwhile, improving thermoelectric technology that converts heat into electricity is being fitted onto everything from car exhaust pipes to furnace flues.
It's … Read more