It’s time to start thinking about your light bulb purchases in terms of both watts and lumens. Watts measure electricity consuption, not brightness. The measure to consider for brightness is lumens. To save energy, choose the light output you need (lumens) that uses the lowest amount of watts. Follow the lumens link above for a chart that compares typical lumen output between compact flourescent and incandesent bulbs.
Credit: Energy Star article
