About LED technology:

LEDs are chips of semi-conducting mineral compounds created by depositing two thin layers of materials onto a substrate, one with an excess of electrons and the other with a deficiency of electrons. The flow of electrons from one to the other generates a miniscule electric current causing photons (light) to be emitted.

Advantages of LEDs:  

• produce substantially more light per watt than incandescent bulbs, theoretically generating the luminosity of a 40-watt incandescent bulb, using only 3 watts of power.
• are designed to focus their light. Incandescent, fluorescent and halogen bulbs require external reflectors to direct light.
• are solid state components, so are difficult to damage with external shock. Fluorescent, incandescent and halogen bulbs are easily broken.
• have an extremely long life spans. Their ETTF (Estimated Time To Failure) has been estimated to be between 100,000 and 1,000,000 hours. Fluorescent bulbs typically are rated at about 30,000 hours; incandescent and halogen light bulbs are rated at 1,000-2,000 hours.
• light up very quickly.
• do not get hot.
• do not contain mercury, while compact fluorescent bulbs do.