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With the present technology for grid control, widespread, distributed power sources make for an almost unmanageable entanglement of sources and loads. As one who has sat in the “hot seat” of a regional grid dispatching center, I can tell you that nothing gives you more headaches and nightmares than trying to juggle a bunch of small, intermittently-operating generating sources and balance a demand curve that has a huge, voracious baseload component (industrial and large-scale commercial) that must be satisfied, topped by a fluctuating demand that shifts on an almost hourly basis (i.e., residential and lighter commercial demand). One thing that makes modern grid stability possible is the almost continuous availability of intense, large-scale generating assets (mainly nuclear units), and the ability to keep a reasonable capacity margin through spinning reserve. If we replace that with more intermittent, low-intensity sources, grid stability becomes much more problematic. This, BWT, is the difficulty some third-world countries now face, and is why rapidly-developing countries like China and India want to bring large, central-generating plants on line as quickly as possible to meet rising (baseload) demand.

Interesting points, thank you. But I don’t see this kind of thing being used as baseload supply. If a utility can’t manage having a million grid-tied inverters supply intermittent trickles, then that plan will be shut down quickly.

It seems like useful applications for distributed usage — most especially charging spare, removable electric car batteries which I think is what we’ll start seeing.

There’s an interesting recent story of a guy who just got 8-figure funding for a system of battery swap stations where people could swap out their car batteries like you’d swap a propane tank. Pull into it, the attendant takes 3 minutes to swap you out, and you’re good for another 150 miles or whatnot.

Thank you for your contribution. In my comment about politicians (and let me add greenies) not having any clue about the issues of modern power, I was hinting at the issues you were more specific about. Some of these folks think if they can push a few buttons on a solar control unit of a home installation, that it should be easy for a public utility to do the same.

Modeling the US power grid is a challenge even for very learned people with state of the art software and real-time data resources. Indeed, the difficulties in this problem are exactly why a portion of the existing grid fails from time to time. In real life terms, a million KW of public supply and demand is not just 1 KW of supply and demand scaled up.

That's a very useful and interesting analysis, but your objections appear to be based on the idea of "selling back."

If, instead, we take Hazwaste's approach (use the grid as a battery for when there's no sun), then the flow is still one-way, but with a lower baseline demand.