Page Content 1. UT Extension serves the citizens of Fayette County with educational programs in the areas of Agriculture, Family and Consumer Sciences, Community Resource Development, and 4-H Youth Development.
A large globe light, like around a vanity mirror, that is rated at 25 watts consumes exactly the same amount of energy as a small refrigerator light bulb also rated at 25 watts..  Size as a power ratingThe wattage rating of a light bulb is directly proportional to energy consumed by that light bulb. A light bulb rated at 60 watts consumes 50% more energy than a 40 watt light bulb.
Instructions. Multiply the battery's reserve capacity by 60. With a reserve capacity, for instance, of 120: 120 x 60 = 7,200. Multiply the result by 262.5, the battery's rated wattage: 7,200 x 262.5 = 1,890,000.