That doesn't make any sense to me. It's December, you are in the Netherlands, you are using CFLs, and you were having temperatures over 100F? Are there any things possible heating your closet besides your light? I live in Arizona, temperatures reach over 110F in summer, and I've been able to keep temperatures in the mid 70s using only a fan and my air conditioner. Maybe you need some sort of exhaust up higher in the room to pull the heat out of the room all together. That's the only thing I can think of, that the room has no way for the heat to escape and its simply building up.