In an enclosed space you're going to want to find a way to exhaust the heat from the top, as heat rises. An intake of some kind will need to be allocated low to the ground to catch cooler air that settles naturally at the lowest possible point. Even if it's a passive intake [ i.e.: just a hole ], it should work. Just work out a way to pull the air out from the top, nearest to the light, and you should be fine.

And, like it's been suggested -- work a light schedule that revolves around lights off being during the day, and lights on at night.