Saving the Earth via choice of light bulb 1 15-W fluorescent fixture produces as much light as 1 75-W Incan bulb. The fluorescent bulb lasts for 10,000 hours the Incan bulb lasts for 1000 hours The fluorescent bulb costs $15.00 (which is why no one buys them) The Incan bulb costs $0.75 (which is why everyone buys them) Now lets calculate the total cost over the lifetime of the fluorescent bulb assuming a cost rate of 10 cents per KWH. Fluorescent bulb = 10,000 hours * 15 Watts = 150 KWH * 10 cents per KWH = $15 + the cost of the bulb total cost = 30$ Incan bulb = 1,000 hours * 75 Watts = 75 KWH * 10 cents per KWH = $7.50 + the cost of the bulb total cost = $8.25 Now multiply this by 10 = $82.50 So, over a 10,000 hour period, the fluorescent bulb has a total cost of $30 and the Incands have a total cost of $82.50. You just saved 50 bucks as well as 600 KWH of energy. Clearly always use fluorescent bulbs if you are interested in saving energy and money. However, this requires thinking on the long term!