Light Emitting Diodes (LEDs) are a solid-state light source that has unique properties that make it ideal for efficient and solar powered lighting applications. Although most people think of LEDs as indicator lighting, one type of LEDs is specifically designed for general illumination applications. [More on LEDs http://en.wikipedia.org/wiki/Light-emitting_diode]
As the technology has become more robust, reliable and efficient, LED lighting is becoming more commonplace in everyday life. LEDs for illumination, when properly integrated into a light fixture, or luminaire, should achieve over 80 lumens per watt of efficiency (7x more efficient than a light bulb) and a life of over 60,000 hours (> 12 years). The technology means that in more and more applications the light source lasts as long as the light fixture! [More on LED lamps: http://en.wikipedia.org/wiki/LED_lamp]
Sol exclusively uses LEDs as the source for illumination in our street, parking lot and area lighting systems. The reason for using LED lies in the basic physics of the device. LEDs:
- • Emit light in a controlled directional way,
- • Emit light efficiently and
- • Have extremely long life when properly engineered into a luminaire
Although LEDs are not right for every lighting challenge, in solar lighting LEDs provide excellent efficacy (light efficiency measured in lumens/Watt) and allow the use of precision optics to direct light in precise, repeatable patterns to maximize pole spacing.
LED lighting is a diverse field, it spans traffic lights, to televisions to light bulbs. The types of LEDs used in each application are unique, so Sol only selects high-flux LED lighting for illumination. Use of 5mm style or high brightness LEDs for electronics will result in lower light output and unattractive color shifting. Our approach is to select the highest quality LEDs, follow the guidelines of the International Illuminating Engineers Society (IES), test our luminaires to the LM-79 standards and purchase the actual LED from leading suppliers. [More on LM-79 testing standards for LEDs http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/lightfair8_...
As with any new technology, features and benefits of LEDs need to be weighted. For instance, bluish-white LEDs are more efficient than warm-white LEDs, but most people find warm white LED lighting more appealing. In outdoor lighting, opinions are mixed so Sol has selected an “outdoor-white” color temperature of about 5000K to furnish high color rendering (colors appear to be their true color) and deliver a white light that is a fair balance between less efficient warm colors and very cold blue. In the end, factors like CCT (correlated color temperature), efficacy, CRI (color rendering index), etc should all be considered. Sol provides all of its testing data (LM-79 reports) for public review and understanding for a fair comparison on the technical data sections of our website.