3aafea85_lighting___Energy_Saving_Trust__Lighting_technology
[Description] LEDs are simple solid state electronic devices that allow electricity to flow through them in one direction to produce a small amount of light. Bulbs for domestic use contain a large number of LEDs so that a bright enough light is emitted. LED like-for-like replacements for halogen downlighters are now available from specialist suppliers and some retail chains. They are still expensive, but they are the most efficient option and pay for themselves several times over before they need replacing. [Lighting technology] 
LEDs
Energy efficient lighting | Energy Saving Trust
Lighting technology