According to one article, fresnel lens cut from a rear-projection TV
can reach 1200F to 2200F.

http://99mpg.com/blog/pluggingintothesun/
about 1/5 of the way down, with the headline:
"Old Rear projection TV lens makes solar furnace"

If it's on the internet, it must be true, right?

Finding a junked rear-projection set might be do-able.
Even with a manually aimed lens, and given enough patience for the
weather to co-operate, this might be a nearly-free way to slump the
glass, and it is still available for any future water-boiling and
cooking in the event of an electrical doomsday event.

I never figured that harvesting free energy would be easier than just
plugging something in to the wall, but this project requires
temperatures above what most consumers would ever WANT in their homes.

My tight budget constraint is liking this:
Scavenge a lens from a discarded TV.
Buy a roll of magnet wire and a few dozen diodes.
build an oscillator to drive the inductive loop,
a supercap, and a small pic from the scrapbox.
a few pieces of "art glass" and a roll of copper tape.

Not bad at all. I'll have to go looking for a rear-projection TV
that I can scavenge a lens from.

Lyle
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