how many watts is a heat lights
An incandescent lamp is an extremely inefficient light source. According to the Wikipedia online encyclopaedia, a 100 watt bulb is 2.1% efficient. In other words, it produces about 2 watts of light and 98 watts of heat. A halogen lamp is a bit better. For every 100 watts you put in, you get about 3.5 watts of light and 96.5 watts of heat.