THE WATTAGE ON BLACKLIGHT INCANDESCENT LAMPS IS TOO LOW TO PUT OUT ENOUGH BTU'S(HEAT) TO BE USEFUL. CLEAR LAMPS PUT OUT MORE BTU'S THAN FROSTED, FLUORESCENT SCREW-IN BULBS DON'T WORK EITHER...THEY ARE ONLY FOR LIGHT NOT HEAT. WATTAGE IS WHAT ALWAYS MAKES THE DIFFERENCE...THE MORE WATTS, THE MORE...