I’ve noticed when people are using generators to power a tool or appliance, they always directly plug into the generator. Then the generator is burning fuel reguardless of consumption.

How can that waste be reduced? A simple approach would be to plug your tool into a UPS (uninterruptible power supply) which is then plugged into the generator. This would help capture some of the excess energy when you are not pulling the trigger on a drill. Correct?

Possible flaw in this thinking: lead-acid batteries can only be trickle charged. So putting a battery in series only captures a small slice of the energy waste. Better than nothing, right?

I’m asking because I may need to install a generator for a whole house, and it’s not just for incidents. It will run daily in an off-grid house. So I’m trying to work out how to keep the fuel burn at a minimum and also how to fully exploit the available energy when fuel is being burnt (which should generally be during low sunlight times).

(edit) The UPS idea could backfire. IIRC, some UPSs are designed to always draw power from the battery while charging it at the same time. This is a superior design because it ensures that your appliance gets clean power that closely resembles a sine wave. UPSs that directly power the appliance from the mains and only tap the battery when mains go down have the disadvantage of sending potentially quite dirty wall power with surges and brownouts to the appliance. I think the always-use-battery design becomes self-defeating if using the UPS just to avoid generator waste. Correct? Though I’m confused because I don’t quite grasp how a lead-acid battery can charge as fast as it dissapates energy… I would think the charging would be slower than the consumption and power to eventually be lost.