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[Chance]

Originally Posted by wredman

question for you solar guys

How much generator time will you reduce with average conditions of 300 watts of solar every day. Assuming your daily usage will exceed you solar potential.

Not a solar guy but will give you my educated guess.

As with most things, it depends on many factors. But you can make reasonable assumptions and get close to the right answer, which can't be known exactly until you try it.

First, how efficient is solar system -- they are not all equal. If you're talking about 300 watts of nominal panel capacity, and installed flat on roof, I'd guess you might get "about" 1,000 ~ 1200 watt-hours of energy into batteries.

On a 12 Volt system that's roughly 100 Amp-hours. It's really not that much.

So how long would it take a generator to offset 100 A-h? Mostly it would depend on converter capacity, how many batteries are there to accept the charge, and what type of batteries they are. With lithium batteries that accept charge faster, as an example, combined with high-capacity converter, a generator may accomplish the same energy in an hour or so.

With 4 flooded batteries it would take less time than with 2 similar batteries to store the same 100 Amp-hours of energy, etc.; provided converter can deliver current capacity.

Some of the entry level motorhomes have limited converter capacity, and small battery bank capacity, so it could easily take 2 hours, maybe a little more.

In my opinion it could vary a lot, but I can see roughly in 1 to 2 hour range being fairly common.