LED light bulbs save a lot of money. They typically use 515% of the energy that a normal incandescent light uses. They do not have the mercury that compact florescent lights have. LED lightbulbs also last a really long time compared to incandescent light bulbs. In many cases over 50,000 hours compared to a typical 1500 hour life for an incandescent bulb.
Cost savings for LED lights are calculated based on the savings found over the lifetime of the LED in energy consumption. They do not include the time, effort and expense of replacing an incandescent bulb 30 times or more over the life of a replacement LED light bulb.
For the math inclined here is the assumptions used to determine the cost savings of a LED light:
LED lifetime is based on 12 hours of use each day. Lifetimes are based on manufacturers statistics normally from 30,000 hours to 100,000 hours. Cost of electricity is based on 10 cents per kilowatt hour. This number is not representative for all states, for example California costs are substantially more than 10 cents.
For example: a typical LED 7x1 watt LED bulb replaces a 75 watt incandescent and lasts 50,000 hours. The savings of 68 watts times 50,000 hours equals 3,400 Kwh. At $0.10 per Kwh the savings is calculated at $346. The savings are actually more as this number does not include the cost of time and energy to buy and physically replace an incandescent 25 to 50 times over the life of the LED. That would require more math than we want to write about to right now.
