I have not left the garage on this one. I did run the roof top unit for about 25 minutes but cooler weather might not have had the compressor running. Microwave seemed fine on heating a cup of water.So from recent comments another battery in series would possibly give say half an hour on a/c? In all reality my usage with the generator has been the microwave or tv or coffee machine. Our travel has been mostly in fall-spring and in parks at night. Very little a/c use.So this still might be a compromise, but looks like a win/win for us.