I was looking back at reddit posts (while deleting them), and I realized I’d written a book worth of stuff about this topic. I would write it all again, if it is helpful. But for a brief synopsis of “how it works”, here is what one does:
Assess power needs - look at your living standard and catalog all the devices you power, and estimate the time they operate - power is measured in watts, and time in hours. Multiply to get watt-hours; then divide by 1000 to get kilowatt hours. Compare with your utility bill.
Excellent idea with the freezer to fridge conversion.
I thought of hooking up the washing-machine directly to my solar-thermal hot-water system to save energy, but apparently that is very difficult to control and the washing-machines made for it are indeed very rare and super expensive. But I guess that is only a problem in the slightly colder climates.