28 November 2010

The immense power of sunlight


What's important about the video is not the fact that focused sunlight can melt rock, but that for the demonstration shown, the sunlight used was that which fell onto an area only 2 square meters in area.

As pointed out at Reddit, you can do this at home with a giant Fresnel lens, and you can harvest such lenses from discarded rear-projection televisions.

3 comments:

  1. expatQLDNovember 29, 2010 at 7:59 AM

    Shoot, I just took our old rear projection TV to the tip. If I'd known this I'd of kept the fresnel lense for a home experiment for the kids.

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  2. PeteNovember 29, 2010 at 10:40 AM

    And why aren't we using this to generate copious amounts of electricity?

    ReplyDelete
  3. MinnesotastanNovember 29, 2010 at 12:57 PM

    Pete, I've lost a link I saw earlier this week claiming that if the U.S. had put the same amount of subsidy $$ into solar as we have into oil over the past several decades, we would be solar-powered.

    ReplyDelete