Jim:
A short comment on using any power source without a governor to drive a generator. While it will work, it will not maintain a constant voltage or frequency under varying loads. I am 69 years old and have watched people build “tractors,buzz saws, water pumps etc” over the last 60 years using car or truck engines. Usually with very little luck. A tractor has a decent governor and will maintain a near constant RPM from about 10 % to 100 % load. Old tractors often used oil pressure to control RPM, don’t know about the modern ones as mine was built by Case in 1964 and still works great. A lot of Ford 8Ns still in use were built before that. Many people have used a snow blower and it indicates how a good governor works. The unit runs at nearly a constant RPM as you use it and the load varies from near 0 % as you approach the snow, to near 100 % of its usable output as you go into the snow bank. If the governor is disconnected or fails, the unit is unusable for all reasonable purposes.
The major reasons for using a PTO generator are all given in the link, low RPM motor with excellent governor, used often so fuel and engine are fresh, easily portable as it usually is on a 2 wheel cart attached to the tractor, and you have a power unit that can be used for many purposes every day.
My personal choice is a 20 or so HP unit, compact, low noise, fuel efficient, reasonable cost, available in diesel or gas, can be used in the woods or for small scale farming now and for any number of things if TSHTF. – JDT
JWR Replies: Thanks for your comment. Until you mentioned it, I hadn’t remembered that constant RPM (via a governor) was crucial. Home lighting, pumps, and traditional refrigerators/freezers are relatively flexible on input voltage, but most home electronics are not. Unfortunately, with each passing year, more electronics creep into what were heretofore purely electrical appliances. Even some brands of mundane chest freezers and washing machines now have electronic circuitry including microchips. This has three major drawbacks: 1.) Vulnerability to EMP, 2.) Greater difficulty for individual owners to do their own repairs, and 3.) The requirement for relatively “clean” input power in a fairly narrow input voltage range. The latter is something that many generators cannot provide.
On a related note, SurvivalBlog reader “Poikilo” mentioned that some of the new hybrid trucks on the market (such as the Chevy Silverado Hybrid) can also in effect be used as a generator. The question is: Are the truck’s 110 VAC outlets sourced directly from an AC winding on the hybrid engine generator, or are they powered by an inverter that draws on the vehicle’s batteries? I’d be curious to know what sort of load those 110 AC outlets could handle.