LEDs have a bright future
Light-emitting diodes (LEDs) haven’t enjoyed heavy usage outside of exit signs and “OPEN” signssmall instances where their energy efficiency and long life offsets a high upfront cost. More frequently, companies looking to save energy have purchased compact fluorescent bulbs (CFLs), which use 40-75 less energy than traditional lighting, and can be purchased for only a couple of bucks. Alternatively, LEDs have usually hovered above the 30 range. That is, until recently.On the New York Times Green Blog on August 11, Leslie Kaufman reported that Home Depot was selling LEDs for under 20 online. The bulbs were not expected to fall under 30 until 2012the year when all bulbs sold in America will be required to be 30 more efficient than current incandescent options.The real cost benefit with LEDs is their lifespan. These bulbs are expected to last over 30 years, and cost only 1.50 in electricity per year. Alternatively, CFLs cost around 3 in electricity a year, and a 60-watt incandescent light bulb costs around 12 a year, while also having a shorter life expectancy. Another issue that has been keeping consumers from switching is the quality of light difference noticed between incandescent bulbs and CFLs. CFLs often have a less powerful brightness when compared to incandescent bulbs. However, with a good-quality LED, you’ll hardly notice the difference.According to Wikipedia, LEDs work by recombining electrons inside electron holes within the device, “releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. An LED is often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern.”In addition to the lowering prices, many state-level programs are offering rebates for companies who install LEDs. One such program is Efficiency Vermont, offering 30 rebates for businesses that install Energy Star-qualified LEDs, and 150 rebates for LED track lighting. Alternatively, Tampa Electric offers an incentive of 175 per kW for lighting upgrades of any kind and 25 for upgrading exit signs to LED.