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To: DUMBGRUNT
I'd like to know details. Is it legit?

I know people who complain about solar and/or battery backup but didn't do the math ahead of time and are, therefore, unsatisfied. And I'm sure it's possible that the complaint is legit.

For example, the grid in my neighborhood has been down twice this morning (once before the sun came up), and it's a drizzly rain day (currently about 850W coming in through solar). I don't know why: it didn't storm, maybe a car hit a power pole. And my inverters are set to drain the batteries until 30% charge left before pulling from the grid. In a grid-down situation pull from the batteries until 20% charge left. The difference (10%) gave me a 9kWh storage buffer (10% of the 90kWh battery stack is 9kWh). About 5% to 7% loss when converting DC to AC power and call it about 8kWh before I have no power (with multiple back-to-back days of rain not charging my battery stack all the way, thus pulling from the grid at night until the battery stack was 30% charged this morning). Thus, I told my wife that until the grid came back up, no getting in the hot tub this morning or running other heavy appliances we can hold off on. That 8kWh in reserve gave us plenty of power for our more essential things. In other words, I know the strengths and weaknesses of the system.

If yesterday had been a sunny day (and fully charged our battery stack while providing all the power we needed in the home and charging the EV) and we had sunny weather for today, I would have told my wife to run whatever appliances she wants.

4 posted on 12/02/2025 6:56:20 AM PST by Tell It Right (1 Thessalonians 5:21 -- Put everything to the test, hold fast to that which is true.)
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To: Tell It Right

People are not interested in doing all that mental work for something they take for granted. (Engineers excepted, of course.)


6 posted on 12/02/2025 7:20:08 AM PST by smokingfrog ( sleep with one eye open (<o> --- )
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To: Tell It Right

There is a niche market here — a wall thingie that does this thinking for you. After market.


9 posted on 12/02/2025 8:05:35 AM PST by bobbo666
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