We had 3/8in chains for both of the family diesel & gas generator in a locked shed, and 1/2 miles private drive way with a 5in steel bar gate...The thieves bent the gate post, and some how manage to break through the shed cut the chains and drag the damned generators out of our property.
...It doesn't matter what you have for prevention, because the thieves will find away to steall it if they are desperate enought.
I don't know where you are from, but I sugest a shot gun loaded with rock-salt would be the best prevention.
I'm against guns, but I was tempted to get one if the Canadian gov alow guns. It is fustrating to come home and find your home & belonging is violated, and add ontop of that you don't have electricity or running water due to the lost of the generators.
sorry to hear about it lowtech but I think you're screwed as far as the Canadian gov't changing their stance on firearms. That whole operation was a fiasco and quite a few people are very pissed that the gov't lied when they presented numbers to support their case. Now if folks south of the boarder can retain some common sense and back-bone, it won't be repeated in the US.
aic, as for a method for securing your generator; consider using solid metal strap or angle iron, with a hasp and lock. You can set the lock in a metal housing so that only your fingers can reach in with a key to unlock it. This makes it nearly impossible to use bolt cutters on the lock. Seen this set-up on a gate; while it slowed you down unlocking it the added security caused more then one vehicle to become stuck as they tried to drive around the gate.
as for the shotgun: good intention but nowadays the average citizen has more restricted rights then the criminals. But hey!!!! Big Brother is there to protect you,.....................in several hours.
My suggestion would be to build a concrete with lots of rebar enclosure around the generator. Sort of an outhouse. Just make sure you put up the wall to this outhouse after you install the generator. Also make sure the door on the outhouse is too small to fit the generator through.
I don't know what kind of generator you have, but my parents have one you run off the PTO shaft of a tractor. It's bolted to the garage floor. Maybe you can do something similar and then weld the nuts in place after you tighten them down. But if you don't have a cement floor then this plan won't work.