July 2010

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« He came, he saw, he left muttering... | Main | Away from Criticism »


Lee Felsenstein

I hope that JD Baldwin does not think that I claim that a laptop cannot run at all on a battery charged by a hand crank. The question is how long the laptop (or any load of a few watts) will run on a charge generated by how much cranking against how much resistance. I have published my calculations in this blog - nothing any critic has said here has contradicted them.

Please, if you feel that I am wrong, address the calculations. Your statements should be reviewed by someone with basic electrical engineering or physics skills (it doesn't take much).

The crank power issue is dead now, as witness the statement 1) above. I am working on development of a pedal-powered generator which can generate 60 - 70 watts of power over extended periods of time. There has been recent progress on this and I will report on it when I have permission fromothers who are involved.

J D Baldwin

A laptop batteries can be recharged by a hand crank. Also a clockwork 'battery' system could power a low end laptop, as below:

On a BBC program - "tommorows world " late 1980s/early 90s they had Trevor Bayliss of the windup radio fame on. Where he had slightly modified one of his radios with power out up socket on the back. Guess what, he plugged a laptop into the socket and it worked.

Jecel Assumpcao Jr

Just a small clarification: the $20 textbook number often cited is how much the Brazilian government currently spends each year per child in textbooks (several per child). So if the Laptop can replace all books for five years in a row with no extra costs it would break even.

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About Lee Felsenstein

  • Based in Silicon Valley, Lee currently does electronic product development, due diligence, expert witness assistance as well as speaking engagements and participation in conferences such as the O'Reilly Emerging Technology conferences. The most unusual places he has spoken were at the Waag in Amsterdam and a squat in Milan, Italy. He was named the 2007 "Editor's Choice" in the Awards for Creative Excellance made by EE Times magazine. He holds 12 patents to date.