Have chickens in a few weeks. No pigs this year cause the baby is coming and been slammed on the house. Might try to pick some up in a couple weeks to process it early next year even if small.
Ecoflow are good. I have a jackery which is decent. Works well for my needs but if you can put it somewhere where noise isn’t an issue, I would get a gas powered one. I would bet your heater would run through a solar generator. What’s the wattage usage of it?