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Re: [Phys-l] MIT breakthrough in practical water electrolysis



At 12:44 -0700 8/5/08, Roger Haar wrote:

In many ways the interjection of "solar energy" is a red herring in
this news brief and in the article in "Science". As I understand
straight normal electrolysis, H and O are generated. These after
leaving the electrodes they may form H2 and O2, releasing a fair
fraction of the energy needed in the electrolysis. The group form MIT
have improved the efficiency of electrolysis by forming H2 and O2
directly at the electrode which does require less energy than forming H
and O. Additionally, the setup is simpler than the previous systems and
works with a less expensive, less picky and less toxic brew.

It's not a red herring in this sense. The big issue with solar power, especially in homes is what to do when the sun goes down. At certain times of the year, notably in winter, the peak power demands are in the early evening, just after sunset and in the morning, before the sun is high enough to provide much power from the PVs. If you don't have smart metering in your area, or you only get credit for returned electricity at the rate prevalent at the hour it goes back, you end up getting a credit for your returned electricity at a lower rate, or having to store it somehow, and in either event, you will end up buying electricity at the highest rate.

So if the claims being made for this means of electrolyzing water pan out, it will be able to provide the individual homeowners with an affordable storage system that that will enable them to use or resell their electricity at times most favorable to them, or, if the PV system is independent of the grid, provide power to recharge their PHEV or EV overnight.

Thus, although it is clearly not directly related to solar power, it might complement a solar unit very nicely under certain circumstances. That is, if it turns out to be everything that is being claimed for it now, and ends up being relatively cheap to install, and of course it will have to be mated with an equally affordable hydrogen fuel cell. So there is a ways to go before this will become the answer to a polar bear's prayer.

Hugh
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Hugh Haskell
<mailto:haskell@ncssm.edu>
<mailto:hhaskell@mindspring.com>

(919) 467-7610

So called "global warming" is just a secret ploy by wacko tree huggers to make America energy independent, clean our air and water, improve the fuel efficiency of our vehicles, kick-start 21st-century industries, and make our cities safer and more livable. Don't let them get away with it!!
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