I'm not a huge fan of Diesel.
- It has to be pumped out of the tank
- It has a finite lifetime of about 6-12 months.
I'm a little leery about a used cell site backup generator, they are sold for a reason. And it is surprising that there are 0 hours on it, that's enough reason for me to reject it. If it hasn't been exercised periodically, then the gunk isn't blown out and the moisture isn't cleared (allowing rusting)
I'm looking at a 30kW industrial generator
Powering your home, your business, your world. that's only $12,000.
My 60kW has 13 hours on it after just a year of weekly test runs.
Personally, I would frame it up as planning for outages takes preparation, whether it is splitting, drying, and stacking firewood, or arranging for backup electrical supplies. You can put propane in a tank and use it ten years later, if it hasn't leaked out. (Just because it went in, doesn't mean that there isn't a leak, or that a gasket can't go bad. "Trust, but verify.") If you want propane power, do
Gasoline and diesel fuels are different and need care; they aren't shelf stable and you can't just pour them in a tank and expect them to be ok.
- You can buy cans of engineered gasoline, e.g. TruFuel, that can last up to five years, or racing fuel in sealed cans, which can last much longer. Untreated gas from the pump is good for three to six months. If you have a way to rotate your fuel, that is great. Otherwise, plan ahead.
- Diesel fuel is hydroscopic, so you need to either prevent moisture from getting in, or have a process for removing it continuously. It is also a good idea to have your diesel treated with an algicide on a scheduled basis, and get the fuel filtered to help keep the fuel clean and free of gunk. Both are easy to do with a recirculating pump and an extra filter, dosed with algicide when installed.
I have used and bought a number of generators, and while a used generator can be in any condition, ex-industrial, and ex-military generators can be found that were never put into service, and at a big discount to retail. If you are buying from a big company, and the unit is five years old or older, it probably either was surplus to a project, or just hit the depreciation limit, but the devil is in the details. My $0.02 is that if you aren't familiar with the ins and outs of standby/prime power generation, trying to DYI is likely to have a steep, and potentially expensive learning curve.
Generac makes things pretty simple for homeowners, if you can use natural gas or propane. Just do a little checking on who the local installers are, and there is a big difference between residential only and commercial technicians. Like many things in life, some are better than others.
The OP,
@blperk, wrote that they weren't interested in propane or diesel, which leaves solar, hydro, and wind for residential use.
All the best,
BG
