Could be diesel or propane either way wouldn’t have been hard to design a box for it to sit in so that the fumes could still go outside.
After an apocalypse like that it’s unlikely that solar or wind would be very viable it would most likely be nuclear winter so that would stop both as solar is not going to get any sunlight and a windmill is going to require excessive maintenance to stay functional in that.
The better bet would still be battery bank but battery bank with generator that way you’re not just wasting electricity since a generator is a demand-based response but still uses a set amount of fuel no matter what just to run you use the generator to charge up the battery Bank and then use the batteries only turning on the generator when they need to recharge















Meanwhile i have a linux server that’s currently running individual LXC containers for hosting
Snipe-it, zammad, paperlessNGX, wiki.js, rustdesk server, firefly III, flare, among a few other things. And it’s barely using 6GB total. Less than windows sitting at desktop these days. It’s pathetic how bad windows has become.