Using a residential PV panel on RV
Hi everyone, Newly registered to the forum here, I've been reading a lot of helpful information here over the past year while doing my conversion though. I haven't been able to find a straight ans...
Forum Discussion
Hi,
I do understand your desire to be minimalist. I mostly boondock.
I love danfoss compressor units, but the makers are claiming 3 amps per hour @ 12 volts. That works out to 72 amp-hours per day.
Remember, if you want the bank to last you don't have 230 amp-hours--you really only have 115 except in dire emergencies where you trade off cycle life for convenience.
Due to the Peukert effect doubling the capacity more than doubles the resources at your disposal.
If you have purchased nothing so far, I'd definitely go to 24 volts and 4 batteries.
Do you plan on giving up the wobbly wide web? If not, how many hours per day will a laptop be running.
By going to 24 volts for the battery bank, you can use a larger higher voltage panel and a cheap controller (do get one that is temperature compensated). The savings may more than pay for the extra batteries. Voltage at 24 means line losses are cut in half on dc wiring.
Once you buy items on one voltage you are pretty much committed. Yes, you can, like 2oldman use a DC to DC converter to move 24 down to 12, but that is an extra cost, and causes some system parasitic losses. And DC to DC converters, as good as they are, are still not 100% efficient.
As batteries age, they loose capacity. Build in enough over capacity, and the battery bank lasts a lot longer.
Finally, it is always better to have too much capacity, than not quite enough.
I do understand your desire to be minimalist. I mostly boondock.
I love danfoss compressor units, but the makers are claiming 3 amps per hour @ 12 volts. That works out to 72 amp-hours per day.
Remember, if you want the bank to last you don't have 230 amp-hours--you really only have 115 except in dire emergencies where you trade off cycle life for convenience.
Due to the Peukert effect doubling the capacity more than doubles the resources at your disposal.
If you have purchased nothing so far, I'd definitely go to 24 volts and 4 batteries.
Do you plan on giving up the wobbly wide web? If not, how many hours per day will a laptop be running.
By going to 24 volts for the battery bank, you can use a larger higher voltage panel and a cheap controller (do get one that is temperature compensated). The savings may more than pay for the extra batteries. Voltage at 24 means line losses are cut in half on dc wiring.
Once you buy items on one voltage you are pretty much committed. Yes, you can, like 2oldman use a DC to DC converter to move 24 down to 12, but that is an extra cost, and causes some system parasitic losses. And DC to DC converters, as good as they are, are still not 100% efficient.
As batteries age, they loose capacity. Build in enough over capacity, and the battery bank lasts a lot longer.
Finally, it is always better to have too much capacity, than not quite enough.
