Gravity, Shmavity

The "gravity powered lamp" that a lot of people blogged about recently is only theoretical and will not work as described:

So you need to lift a 4000 kilogram mass 1.5 meters to run this for 4 hours, and that's assuming a 100% efficient generator. Either that or you need to lift the 50 pound mass 57600/(22.7*9.8) = 259 meters. Either way, you need something on the order of 175 times more energy than they have available.

"Inventor's" response:

If there's any question as to the legitimacy of the competition now, I have offered to graciously concede the 2nd place win, as well as any winnings. My job now is to figure out a better design, plain and simple. I made an estimation based on feedback I got during the design process, and that estimation was shown to be incorrect.

via Swallowing the Camel