wap wrote: ↑Thu Feb 11, 2021 6:09 pm
Detroit wrote: ↑Thu Feb 11, 2021 5:15 pm
Natural gas for the furnace, electric for everything else. Eventually I'd like to do solar with some sort of battery backup (powerwall or something) which would drop our energy bills to next to nothing.
Full transparency, the bunker is in a

area. All the power lines are buried, and we've only ever experienced one power outage that lasted 2 hours. Our neighbors claim we usually only get one power outage a year, and because of the area

we tend to get priority for fixes so they never last longer than half a day at most.
Right, but if you're "prepping/notprepping" you'll want some real back up, no? I mean, solar as a primary back up that far north is

, no? I know how many non-sunny days we get down here...
And, a half day in the dead of winter or the heat of summer can really suuuuuuuuuuuuck.
Although, your buried bunker should be somewhat protected against sudden, wild temp swings.
I need to go into some of the

behind how the house was engineered and designed.
Built into the hill, facing exactly south with all windows on the south side. The placement of the roof and windows was designed specifically to let sunlight in the house in the winter, but have sunlight hit the roof (buried in the ground) in the summer. A sunny day in the winter it can reach 74 in the living room without the furnace turning on once, even if it's 10 degrees outside (happened last week). And the concrete is heating up, so it retains that heat well after the sun goes down. You're right, the house takes a long time to drastically change temperature as a result.
I wouldn't view solar as a backup but as a primary energy source with the grid as backup. The house doesn't use a ton of energy by nature, so solar with a good battery storage thing could probably be primary most of the time. Because of the sun exposure, solar panels could be as efficient as possible in Michigan, which on our hill somehow ends up getting an

amount of sun compared to Detroit. I think it has to do with our elevation and proximity to water (surrounded by big water) that messes with the clouds and weather patterns. But even when it's somewhat cloudy, the sun manages to get through a bit, our plants in the window sills are going insane this winter.