Efficiency
LED products deliver the same amount of light as conventional products, using as little as 10-15% of the power. A 10 watt light can replace a 56 watt incandescent. In its 50,000 hour lifetime, it will consume about 525 kilowatt-hours, costing about $63. A typical incandescent lasts only 2,000 hours. To match the LED, it would consume 3,250 kilowatt-hours and need to be replaced about 25 times, costing over $465.
The LED method of producing light loses far less energy to heat than do other lighting technologies. It's dramatically more efficient than the vacuum/filament method used in incandescent bulbs - around 85% more efficient.
Even though the bulbs are more expensive, LEDs will save money in the long run, as one is needed, every decade or two, with much less money spent on home lighting, which can account for close to 10% of home electric bills.