I use a 100 watt MVB during the day which is on a timer and provides heat and basking opportunities. If the temp drops too low, I've got a CHE on a thermostat. If during the day the temps drop, the CHE kicks on. And at night it provides the heat and darkness needed for proper slumber.
The only light we have found so far that hurts tortoises yes are the coil type or compact fluorescents, that I know of anyway. A good combo to use is what Ken mentioned. Unless you can get your tort outside for natural uv a few times a week then you may need both.
Can you show us a picture of the enclosure, state its dimensions and the species and age of the tortoise you have? This info will help others give you a better answer.