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1. marksb+ll[view] [source] 2023-09-13 21:36:01
>>bookof+(OP)
So living on a narrowboat in the UK this is something I have experience with. We have a 335 W panel with an MPPT connected to a 200 Ah 12 V flooded lead acid battery. The battery in reality has a capacity of half that and in the 6 years of seasonality it has probably halved.

A few things :

* you don't need a fridge in winter so you can just turn it off. * charging battery banks / laptops in sunny periods results in the battery bank being useful in times when the weather isn't so kind. * no amount of solar is enough in the deep of winter. * any amount of solar is too much in the height of summer. * pubs are great for charging devices. * lead acid batteries last substantially longer if you only let them drop to half their true capacity and regularly charge them. Yes alternatives exist but there's something to be said for making what you have work for as long as possible.

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2. verisi+Co[view] [source] 2023-09-13 21:52:49
>>marksb+ll
> no amount of solar is enough in the deep of winter

> any amount of solar is too much in the height of summer

I totally agree. I can't understand how it why solar is promoted, when the winter is when you need more energy as you're in more, heating your house, etc. You can't store your summer's energy till the winter.

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3. Retric+Gr[view] [source] 2023-09-13 22:14:42
>>verisi+Co
Rooftop PV isn’t the best plan if you’re north of NYC. The grid can far more efficiently move power from Southern areas that don’t need significant heating in the winter up north. The transmission losses are vastly lower than the gains you get from longer days. And as a bonus you rarely need summer cooling while people south of you do.

However, if you’re in Main and don’t have a ground source heat pump then solar thermal works great. PV is panels are still only 22% efficient and you air source heat pumps don’t work well in ultra cold weather, worse you need batteries for the long nights. But with solar thermal you’re looking at ~90% efficiency for heat collection and ultra cheap energy storage in hot water tanks. You do get less power per m2 of collection area, but that’s offset by needing heat for a longer period.

Off grid solar can work in the surprisingly far north, just expect a significant premium.

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