RV Solar Series: How to use the Generator with Solar. The sun doesn’t shine every day so you can’t expect that solar is going to be your only power supply. My solar coupled with a bigger battery bank of the right kind of batteries could bridge multiple cloudy days and return to a full charge in a couple of days. My solar is matched to my batteries to recharge them on a daily basis. This assumes that the sun shines the next day. I must recharge my batteries on a daily basis to maintain their health. I cannot bridge a cloudy period without running the generator.
If you want to make me cry, turn on the generator so you can microwave a cup of water for a minute. Equal to that would be to use my 7000-watt generator to charge the battery. My generator has the ability to produce way more energy than my solar. Unfortunately, my battery isn’t able to accept anywhere near that amount of energy during a short duration. My generator is way overkill to charge the battery.
Using my generator to charge my batteries is not as easy as it may seem.
In fact at maximum, my generator is only using way less than half of the available electricity to charge the battery. To recharge my battery it takes at least a couple of hours. After only a little while, the amps delivered to the battery trail off. When that happens, the generator is still doing little other than making noise and wasting gas. Remember Bulk, Absorb and Float apply regardless of energy source. All last year I recharged the battery on the generator and it was painful.
A possibility is to use the generator first thing in the morning to give the bulk charge a head start. After this let the solar take over for the remainder of the charge. This plan may be an especially a good option on days where the sky is bright, but the direct sun is not expected.
Another possible use that will recharge my battery, is to anticipate needing the generator to create enough power to run the air conditioner. This doesn’t happen very often because I plan my location not to need air conditioning, or at least not require air conditioning very often.
Solar panels love to have direct sunlight but are willing in cloudy days to put out enough juice to top of the battery, and run many of the loads while they are doing so, even without a blue sky.
Always remember lead-acid batteries love to be at 100% charge and suffer if they are not returned to 100% soon after discharge.
RV Solar Series: How to use the Generator with Solar for me the answer is that my generator is a great addition to my ability to create power when it is needed.
Update January 20, 2020, all of the above data assumes operation on lead-acid batteries. Much of this changes when you have lithium batteries. Make sure to follow us on our 2020 electrical remodel of a very power-hungry RV.