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.
> 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.
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.
It is way too much power cause the thing is constantly being charged every time the sun shines and it is pretty hard to use 300ah in a campervan while you're sleeping.
The benefit of LiFePO4 over those AGM batteries, is that you can go to zero. It is worth every $ for that and for the weight savings (in a campervan).
Highly suggest checking out Will Prowse on YT. He's a great resource.
People hardly realize (or straight up don't realize) that once you're in the tropics even the notions of summer and winter start to get fuzzy. Consider: if you're on the equator then you can go from "summer" to "winter" in only a few steps. Obviously, near the equator solar is a no brainer.
And of course the opposite is true, once you're inside the arctic circle solar is basically pointless because there literally is a period of no sun lasting anywhere from several days to several months. Of course not too many people live inside the arctic circle so it's not too much of an issue.
Even between these extremes though, the usability varies a lot.
Solar is never likely to be as important in the UK as it is for the US, but even so it seems it can be helpful because solar generation is at its highest during the summer when wind generation (over a quarter of UK total generation) is lowest.
Mine doesn't have an internal heater, so I make sure to keep it disconnected from the solar panels when it is cold out.
I live in a warm weather area so it was worth the cost difference for me at the time. Worst case, I can just get a simple 12v heating pad for it.
[0] https://www.relionbattery.com/knowledge/how-do-lifepo4-batte...
Worldwide, the ground itself, a few feet down, stays at about 50F year-around ~~ regardless of outdoor temperature. Locally, summer heat-pumping could be directed underground in some places. Reverse in winter.
Pumping heat from where it's stored is a lot less expensive than transporting and burning fuels. We do need to get better at it.
Even here in Montana, the heat going out in the beginning of winter for a few weeks was not really as obnoxious as some of the really hot days with no AC I've seen.
I've often read that the solution to this is to get "deep cycle" marine batteries.
Have you thought about micro wind turbines? I wonder if those would provide some power in the winter just to charge phones and laptops.
It depends what latitude you are whether the (societywide) heating load in winter or the AC load in summer is greatest. And that breakpoint is moving north all the time.
It is quite dramatic how much cheaper and longer lasting the panels are, though.