I have two of the hydrofarm on/off thermostats that I can use for that purpose probably... I read on this forum awhile back that pulse/dimming stats don't work with a generator? We had no power for 2 weeks after hurricane Sandy but had intermittent generator power so it'd be good to have an on/off backup if that's true...
ETA: I guess I should mention that the generator we used isn't a whole-house generator.