How does Wattage relate to light output?
Wattage is a measurement of the electricity usage of a bulb. Lumens is a measurent of the total light output of a bulb. The efficiency of a bulb is calculated by comparing the light output to the energy usage. The efficiency of a bulb is similar for light bulbs of the same type, so you can expect that by switching from a 100W to a 150W regular incandescent bulb that you will get about 50% more light. However, If you switch from a 60W regular incandescent bulb to a 60W halogen bulb you may actually get more light, because halogen bulbs are more efficient.