About the only options I know of are:
1) LED lamps/bulbs -- From what I understand the tech has finally advanced enough to make them worthwhile. Note, however, that the bulbs will cost quite bit more than the fluorescents -- but they will also use less energy and emit less heat.
2) Increase the air circulations via fans.
3) Install/create vents in the "roof" of your enclosure so the heat can escape.
A photo of your "orchid enclosure" would be helpful.