LED vs CFL – Game ON in Side-by-Side Comparison
Working with Molex Electronics, the ZEBRA Alliance, Oak Ridge National Labs, with fixtures provided by Ultralights and Solid State Luminaires, we created a side-by-side comparison between CFL and LED in two identical homes. One uses 100% CFL lighting, the other 100% LEDs. The LED house uses Molex Transcend modular products, which incorporate 4W Seoul Semiconductor Acriche 120VAC LEDs to control costs. While the CFL home was designed by a lighting showroom, the approach in the LED home included redressing lighting design to reduce and elliminate glare, focus on delivering light where it is needed, and producing more attractive spaces that also save energy. The end result is a 70%+ savings over the CFL home. The LED home has less than 0.4W/s.f. of connected lighting load. So little energy is connected, that the entire home could have been wired to a single 15A circuit breaker (920W).
The purpose of this project is to operate both homes with controls that simulate occupied operation over 18-24 months. Over that time the performance of the two homes will be monitored using a sophisticated array of sensors and data aquisition. Lighting is just one small part of the total effort, which includes building materials, HVAC, window glazing, and roofing system performance. There are four total homes, all with identical geographic orientation, within a block of one another. The other two utilize fluorescent lighting, but are different in many other ways, including architectural design.
Below are a few of the rooms of the houses to give you an idea of how the combined approach worked out. As one can see, the difference in appearance is noticeable. At the task level, the LED house provides twice the horizontal illumination on kitchen counters and dining table, matches the CFL in the game room and office (not shown here), and provides a more comfortable light everywhere, as the light sources produce no objectionable glare. So, regardless of the LED employed not being a leading edge lumen/watt producer, the savings remain significant, while the end product – delivered illumination – both attractive and comfortable. This is an approach that will eventually set LEDs up as the preferred light source in residential application – not matching CFL glare bombs, but delivering an improvement in lighted quality as well as energy saving.
For those attending the LEDs 2010 conference this month (Oct 25-27) in San Diego, I will be presenting this project with some background and more detail there. Stop by and say hello if you are in the area: