What Geistware said. An onboard glow driver is a battery wired to a glow plug connector that you can permanently attach to your engine's glow plug. There's usually a switch wired in that you set up on your throttle pushrod so the glow driver gets "switched" on at 1/3rd throttle and lower. Your problem would require having it "on" all the time though, so I'm not sure how long the onboard battery would last.

Much easier, and cheaper to try some aluminum foil around the head.
Dennis-