On Wednesday, June 27, 2012 6:11:03 PM UTC-4, Wayne. B wrote:
On Wed, 27 Jun 2012 11:59:03 -0700 (PDT), wrote:

On Wednesday, June 27, 2012 2:05:53 PM UTC-4, Wayne. B wrote:
On Wed, 27 Jun 2012 09:10:22 -0700 (PDT), wrote:

Another problem not addressed is the battery stores and sources DC, but the power grid is AC. So now we'll have to convert that with big power stations that take DC and convert it to AC. DC motors turning AC generators?

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Absolutely not - high efficiency solid state power inverters.

Being an electronics guy, I thought about inveters... just wondered if you could scale one up enought to power 200 homes, as he says his ultimate big battery will do. Assuming 200 amps per house, that's 40,000 amps. That's one hell of an inverter. And another big heat source, even with the high efficiency.

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There are solid state switching devices that will handle huge amounts
of power with efficiencies in the 90 to 95% range. That's a lot more
efficient than a typical motor-generator set. Of course heat is
related to the amount of conversion loss so higher efficiency means
less heat. I worked in a reserch lab at Cornell University back in
the late 1960s where we had a multi-million watt solid state inverter
for powering the magnet ring of a particle accelerator. The
electronics were not that exotic even then.

I don't doubt it, but that was intermittant duty, and not really mission critical. We're talking about 10 million watts (give or take) and 24/7/365.
5-10% of that is a LOT of heat to dissipate. That particle accelerator could go down for a week and it was not that big of a deal.

This is all cool stuff. We'll get there, where "there" is, one day.