I've run my Honda Eu1000i on Eco mode charging batteries, and 6 to 7 hours on .45 gallon of gas seems to be about my regular consumption rate, if charging with it for an hour first thing in the morning, and topping the battery off with solar the rest of the day. Charger is a Switch charger power supply unit rated at 30 amps and set at 14.8V.
This set up lets the generator do the quick and dirty part of the charge cycle, the 50 to 80% section. The solar does the 80 to 95-98% SOC section.
I do warm my generator up for 3 or 4 minute before I turn on the Power Supply Unit. Important if you want your generator to last, to warm it up properly before putting it under heavy load.
