Picked a random generator off home depot: https://www.homedepot.com/p/DEWALT-8000-Watt-Electric-Start-Gas-Powered-Portable-Generator-with-Idle-Control-GFCI-Outl

Picked a random generator off home depot: https://www.homedepot.com/p/DEWALT-8000-Watt-Electric-Start-Gas-Powered-Portable-Generator-with-Idle-Control-GFCI-Outlets-and-CO-Protect-DXGNR8000/307457717 https://www.homedepot.com/p/DEWALT-8000-Watt-Electric-Start-... 11 hours runtime at 4kW == 44kWh capacity. 44/7.5 gallon tank == 5.8 kWh per gallon. Lets say your EV has average efficiency of 3.5 miles per kWh, so that’s about 20 mpg off the generator. Apply a 13% efficiency loss while charging (https://www.caranddriver.com/features/a36062942/evs-explained-charging-losses/ https://www.caranddriver.com/features/a36062942/evs-explaine...) and it reduces to 18mpg. Better than a lot of cars still on the road.