<human>:  What are the most energy-efficient light bulbs?
<bot>: The most energy-efficient light bulbs are LED bulbs, compact fluorescent lights (CFLs), halogen incandescents, and light-emitting diode (LED) bulbs. LED bulbs use the least amount of energy and last the longest, but they are more expensive than other types. CFLs are also energy efficient and have the added benefit of being easier to find in various shapes and sizes. Halogen incandescents use up to 28% less energy than traditional incandescents and last three times as long.