Is there anything special I should be looking for in a generator when it is being used as backup and battery charging for solar off-grid? I'm considering a Generac Guardian 8000 Watts (propane), year-round, eastern Ontario. It would likely be set to auto-start when the inverter tells it the batteries are nearing 50%.

One issue is whether it's worth the money to pay a few thousand bucks more for something like a Koehler or Onan with half the rpm (1800) and thus a longer life. But I'm not sure what else to look out for.

Thanks,
...Terry

You might also consider diesel. How many hours/year do you expect?

Yes, diesel has the advantages of quiet motor due to lower RPM, longer life for the same reason, and cheaper fuel. It has the disadvantages of manual refueling and higher cold-weather risk, and I haven't seen any around here that are self-standing winterproof (not requiring building a shed). I expect perhaps 4 hrs/week for the cold half of the year, plus an hour per month maintenance during the other half-year, thus only about 110 hrs per year. However this is a fairly rough estimate. What do you conclude from that, Jon?
...Terry

At that low hours, your choice makes sense to me. Seems a shame to burn that propane and let the heat drift away though - maybe you could capture some of it. Or look at micro CHP systems.

If there is an adjustment for how long between the engine starting and when the electrical load is applied, I would set it high - let the engine warm up some before it sees load. And use synthetic oil.

Terry;

I have a 15000 w Generac propane generator that I am well pleased with


jonr;

when power goes out there is a 10 second delay before auto start, then a 10 second warm up before load is applied.