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I am curious how much of a difference it makes.

I have 4kw of panels and 15kwh of storage. I only get down to about 80% most nights (I heat with wood and propane).

But my system will charge completely in about 2 hours of full sun. If it took 3 hours it wouldn't make a difference. So I generally don't clean them (well, the rain and snow do that work).

I do remove snow, because that has a very noticeable impact.

Is the difference that you are pushing back to a grid (I am not), so the power all gets used regardless of you being the one to use it?

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I'm off grid, no mains power, and have 8x48v lithium Fogstar batteries in an external rack, since my cabin is small.

On December 21, due to trees, my panels get around 2 hours of full sun, if the universe smiles on me.

I use around 5-6kwh per day, if I use my computer, which I need for work.

This will be the first year with the fogstar batteries, previously had 1x48v generic lithium battery, but last year I used the generator most days from around end of november until March e.g. December consumption was 153kwh, solar generated 62kWh, and generator made up the rest.

This year, thanks to having more storage, we'll be better able to take advantage of sunny days and capture more power. I also have a freezer and washing machine this year :-) Ask me in March how it went.

All of my panels are easy to access, none on a roof, so the effort is minimal and has non-zero power benefits in my experience.

I should add that I am surrounded by trees and the panels accumulate a green tinge quite quickly, plus bird shit.

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> I also have a freezer and washing machine this year

You need a heat pipe between your freezer/fridge and outside. Then it will “function” when it’s colder outside than in your fridge and otherwise sit idle(ish). Sure you’re bringing “cold” into your big warm box (home), you have wood to overcome that. All theory, but it makes sense in my mind!

(Though in most places, it rarely gets colder outside than in your freezer)

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If they are like me, keeping the fridge from freezing during the winter is more energy that keeping the fridge cooling during winter...
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I can see how small efficiencies would matter a lot in that sitation.

When I had 6 100W panels and was trying to keep my laptop (and lights) running off that, then I did a lot more trying to keep them clean. If I was having to burn fuel for electricity, I'd certainly be trying a lot harder to squeeze what I can out the array.

Anyhow, good luck.

I likely am in a similar position. My hope is to get a cistern buried this year so I can have more than 40L of liquid water on hand at any given time... and then maybe even a shower :D Washing myself with a bucket is starting to lose its charm.

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> I clean my solar panels, 7kwh, every monmth or two.

This honestly sounds like a non-trivial strike against installing solar panels, especially if they’re installed on tall roofs.

I definitely wouldn’t want to have to clean them that often, or pay to have them cleaned that often.

If you’re spending only 10 minutes on them, then maybe you don’t have that many, and they’re not up high.

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Roof-mounted solar panels are a necessity in urban situations but they are a maintenance nightmare compared to a ground-mounted array. That has to be accepted as "the cost of doing solar" when there is no other alternative.
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I never cleaned mine. Rain does enough. It's still plenty valuable without minmaxing them.
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Mine are not on a roof.
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On tall roofs there tends to not be much dust.
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