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Name: Alex S.
Status: Student
Age: 15
Location: N/A
Country: N/A
Date: September 2002

I have heard that the most efficient energy source effectively harnessed by man is nuclear fusion, with an efficiency of something like 0.7% mass-energy conversion. And that the most efficient energy source in the known universe, matter-antimatter annihilation, works at an efficiency of 100%.

Why the huge discrepancy if both works upon the principal of mass-energy conversions? Also, is there another energy source mechanism that works with an efficiency between that of fusion (.7%) and antimatter (100%)?

Matter/Anti-matter annihilation is a special reaction between a particle and its anti-particle. Nuclear fusion is the conversion hydrogen into helium (approximately -- it's more complex than that) which is not the same as the latter. The difficulty in both cases is the engineering problem of harnessing that energy to produce useful energy in a controlled fashion. That problem has not been solved.

Vince Calder

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