There is another aspect to distributed power which I don’t think has been adequately discussed:

The reliability of distributed power should be much better than centralized plants in the event of calamities. Floods, tornadoes, hurricanes, earthquakes, and yes terrorist attacks. Just when power is most needed in the areas which are hit, to aid in recovery efforts. It won’t be available. Outages would still occur with distributed power but they wouldn’t be universal. Often this impacts the availability of water too. Where water must be pumped to users. This makes fire control difficult.

Of course it’s not the generators themselves which are usually taken out by these calamities, but part of the distribution network. At least distributed power would eliminate the long distance power line portion of this venerability.

I know It’s impossible to put a precise dollar value on this sort of thing. But It’s got to be worth something.