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Q & A: hydropower hydrogen

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Most recent answer: 09/22/2009
Q:
If a strong electro static electricity field, can separate hydrogen" and oxygen" from "water" then why can't we build a giant hydro generator at a dam to fuel the countries of the world?
- Todd J. Tocco (age 49)
Rotterdam, N.Y. USA
A:
We have lots of big hydropower generators, relatively clean sources of electricity. The power they generate is used directly as electricity.  It could be used to generate hydrogen by electrolysis, although some of the energy is lost in the process. For most uses there are further losses when the hydrogen is used as fuel, larger than the losses involved in using electricity for the same purposes (such as powering engines). It's possible that with further work on hydrogen storage and fuel cells that it could become more efficient than electrical batteries as a way to carry energy around in vehicles.

At any rate, the total hydropower available isn't a very large fraction of the total demand for power. We need other clean energy sources, and drastic improvements in use efficiency, including eliminating wasteful uses. So you've reminded me to head into the next room and turn off the lights.

Mike W.

(published on 09/22/2009)

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