Watt Tube

January 28th, 2008 admin Leave a comment Go to comments

Watt Tube

Energy saving with LED fluorescent tubes

There are millions of general service fluorescent tubes in the market place today, until recently these were considered the most energy efficient lighting solution available. The downside to this for of lighting is that each tube contains a small amount of mercury vapour, a toxic Heavy Metal. This can provide not just a health risk when the tubes are broken, but can also accumulate in landfills before entering the water table or causing further pollution.

Fluorescent lamps use electricity to excite mercury vapour inside the glass tube and always require a ballast to regulate the flow of power through the lamp. A starter is in the circuit to heat the contact ends of the tube that ionizes the mercury vapour creating UV light. The inside of the tube is coated with a phosphor material that glows when exposed to the UV light produced by the mercury inside the fluorescent tube.

Recent developments in SMD (Surface Mount Diode) LED technology have now meant that LED based fluorescent tubes are now a reality. LEDs are a more efficient form of lighting product consisting of small chips of conductive material that release light when a current is applied to them. They contain no filaments and can produce up to 25 times more light per watt than conventional light bulbs.

LEDs require far less energy in their manufacture than fluorescent tubes, and only 3% of the energy they will consume over their life expectancy is consumed in their manufacture, and they are also produced from non toxic materials. The tubes are made from polycarbonate, a material that is more robust and durable than glass, so accidents will not require special cleanup procedures.

While LED technology is more expensive than existing fluorescents at face value, they will last up to 10 times as long, while consuming 65% less energy. In most general purpose lighting applications they additional cost of the LED technology will more than pay for itself within the first 18 months.

The only drawback is the tighter beam angle of the LEDs, while some tubes are manufactured from a polycarbonate light diffusing material, others have a narrow focus which may not be suitable for replacing existing tubes. Many fluorescent fixtures are designed with reflectors that help to distribute the light from the tubes evenly in their intended environment. This is a problem similar to what was faced when compact fluorescents began replacing incandescent light bulbs, this is a problem that will soon be overcome and allow faster adoption of this emerging lighting technology.

About the Author

Mike Brunt is a director of Specialized Lighting Concepts a New Zealand leader in LED lights and emerging lighting technologies.