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Low Energy Lighting

posted 7 Feb 2010, 09:22 by Toby Roscoe   [ updated 14 Feb 2010, 01:14 ]

The technology behind low energy lighting has has moved on a lot over the last  few years, and so has the way they look. In fact, whatever type of bulbs you use to light your home, office, or factory, there is an energy saving equivalent that is stylish and provides the quality and temperature of light you are looking for. 

The most common type of energy saving light bulbs, called Compact Fluorescent Lamps (CFLs for short), use up to 80% less electricity than a standard bulb, but produce the same amount of light. This is possible because a standard light bulb converts only about 20% of the energy it uses to light, 80% is wasted as heat. CFLs typically pay for themselves in just a few months.

Light Emitting Diodes (LEDs for short - picture right) are revolutionising fashionable downlighting for domestic and commercial applications. Many people confuse ‘low voltage’ with ‘low energy’. Ceiling mounted downlights use a stepdown transformer to convert 220 volt (or 110 volt in North in some places) alternating current (normal mains power) to 12 volt direct current (similar to vehicle electric systems). This process is inherently inefficient as the transformer wastes energy as heat. The 12V halogen bulbs in the socket also waste 80-90% of the energy they use as heat. 

LED downlights, however, are 90-95% efficient as they stay very cool, and are efficient at turning electricity into light. Because they use very small quantities of energy, the number of transformers can be reduced, making an ongoing energy saving for every transformer removed from the system.

The summary is that low energy lighting can reduce greenhouse gas emissions and the lighting component of your energy bill by 80 to 90%. They save you money, fight climate change and show people that you care about the future, all in one wise purchase. 

More from Wikipedia on CFL's:

compact fluorescent lamp (CFL), also known as a compact fluorescent light or energy saving light (or less commonly as a compact fluorescent tube [CFT]), is a type of fluorescent lamp. Many CFLs are designed to replace an incandescent lamp and can fit into most existing light fixtures formerly used for incandescents.

Compared to general service incandescent lamps giving the same amount of visible light, CFLs use less power and have a longer rated life. In the United States, a CFL has a higher purchase price than an incandescent lamp, but can save over 30 US$ in electricity costs over the lamp's life time.[2]Like all fluorescent lamps, CFLs contain mercury, which complicates their disposal.

CFLs radiate a different light spectrum from that of incandescent lamps. Improved phosphor formulations have improved the subjective color of the light emitted by CFLs such that some sources rate the best 'soft white' CFLs as subjectively similar in color to standard incandescent lamps.[3]