Dear Karen, Since wind and solar are out of the realm of reality for most of us, we then begin looking at generators. This leads to some questions you need to have answered before you can make a rational decision. Gasoline generators are usually cheaper to buy. However, gasoline is both dangerous and hard to store. It degenerates after about 3 months into a jelly-like substance that does terrible things to an engine.
Propane is more available.
You can have a 500 gallon tank delivered and installed at your site, along with a contract for automatic service by a local supplier. This means that you have to have a generator that comes set up for propane, or have one converted to use propane. Check out the price of having this done by a qualified service installer. It's not hard to do, and is done all the time in some places. Bad for the soil, but not likely to blow up under most circumstances.