LED LIGHTING – HEAT MANAGEMENT FOR EFFICIENCY AND LONGEVITY
Temperature directly impacts the reliability and performance of LED lighting. In a typical LED light fixture heat is generated within the LED chip and it must have some means of escape. The biggest challenge in designing quality LED light fixtures is getting the heat effectively removed from the fixture which allows the LEDs to maintain light quality and longevity. LEDs are very sensitive to heat; as the temperature increases, the life expectancy and the usable light emitted is reduced. LEDs do not generally fail as conventional incandescent bulbs do. They dim out slowly over time. If the heat is not effectively removed from the fixture, the fixture will dim out much faster. For example, a fixture with proper heat sinking may last for 50,000+ hours.
However, if you put the same LED chips in a fixture without proper heat management, the fixture may only last for a few hundred hours before it dims to the point that it is no longer usable and must be replaced.
Effective cooling of LED fixtures begins with a good fixture design which includes a properly engineered heat sink. It is important to realize that not all products currently being sold are properly engineered and thus will not live up to the light output or longevity claims stated by the manufacturer. Many manufacturers are cutting corners by simply installing LED diodes into existing fixtures which are not designed with the necessary heat sinking technology to ensure that they perform to the stated specifications. Since most LED fixture manufacturers buy their LED chips from a separate LED chip manufacturer, they often use the specifications from the LED chip manufacturer without actually testing how they will perform inside the fixture they are installing them in.
Before specifying or purchasing LED lighting products, it is important to verify that you are working with a product that has been properly engineered and a company that is willing to show and explain all of the key features of a quality LED lighting product.
* Some of the information contained in the article above was obtained from an article in the April 2009 issue of LEDs Magazine written by Françoise Von Trapp, who is a contributing editor of LEDs magazine.
German “heatball” wheeze outwits EU light bulb ban
(Reuters) – A German entrepreneur is bypassing a European Union ban on light bulbs of more than 60 watts by marketing his own brand as mini heaters.
Siegfried Rotthaeuser and his brother-in-law have come up with a legal way of importing and distributing 75 and 100 watt light bulbs — by producing them in China, importing them as “small heating devices” and selling them as “heatballs.”
To improve energy efficiency, the EU has banned the sale of bulbs of over 60 watts — to the annoyance of the mechanical engineer from the western city of Essen.
Rotthaeuser studied EU legislation and realized that because the inefficient old bulbs produce more warmth than light — he calculated heat makes up 95 percent of their output, and light just 5 percent — they could be sold legally as heaters.
On their website (heatball.de/), the two engineers describe the heatballs as “action art” and as “resistance against legislation which is implemented without recourse to democratic and parliamentary processes.”
Costing 1.69 euros each ($2.38), the heatballs are going down well — the first batch of 4,000 sold out in three days. Rotthaeuser has pledged to donate 30 cents of every heatball sold to saving the rainforest, which the 49-year-old sees as a better way of protecting the environment than investing in energy-saving lamps, which contain toxic mercury.
(Reporting by Michelle Martin; Editing by Steve Addison) References : reuters.com