Business Lighting Solutions (BLS) has reported that its LED-based Ecofluro T8 tubes have been used to replace more than 2100 fluorescent tubes at an Auckland, New Zealand facility that houses Air New Zealand's engineering operations. Schneider Electric partnered with BLS on the solid-state lighting (SSL) retrofit that Schneider projects will deliver greater than 50% energy savings.
Replacing fluorescent tubes with LED-based tubes has remained a popular concept due to the sheer number of such lamps installed globally. BLS sales director Paul Stoddart said, "Fluorescent bulbs, which are used by most New Zealand businesses, contribute to around 40% of the average office power bill so by replacing them with LEDs a business can literally halve this cost."
Still, LED-based retrofit lamps haven't proven capable of producing the same level of light output that the latest fluorescent tubes produce according to numerous US Department of Energy (DOE) tests. In May 2011, the DOE published a detailed report of LED T8 tests in a typical office environment. The results found the SSL products draw less power, but also provide less light on the task plane due in part to the fact that the directional LED sources aren't a good match to the troffer fixtures designed for omnidirectional fluorescent tubes.
BLS published photometric data on its website that would indicate the Ecofluro tubes produce greater light output than do the products that the DOE has tested. The summary test data on the company's website is ambiguous, but the detailed report states that a single tube produces 2032 lm. That value is calculated based on intensity measured at 5° increments around the lamp. The LED T8s tested in the DOE study produced 1366 to 1539 lm.
The DOE report concluded that T8s would be a viable retrofit choice in applications where an area was overlit. When asked about the relative lighting before and after the New Zealand retrofit, BLS design and technology director Chris Wheatley said "The light projected on the working plane is +/- 2-5% depending on the color temperature and type of fitting."
BLS is also reporting significantly higher efficacy than DOE tests have documented. The photometric documents on the company's website indicate a lamp efficacy that's over 100 lm/W and system efficacy near that value with some fixtures. A look at the DOE reports show a maximum bare-lamp efficacy of 93 lm/W with significantly-lower system efficacy.
When asked if the DOE had tested BLS products, Wheatley said, "No, to our knowledge they only tested American products and we were not involved. The efficacy of the products tested that I saw were around 70 lm/W whereas we are achieving closer to 100 lm/W. Again this is referenced in the NATA (National Association of Testing Authorities, Australia) accredited photometric reports provided."
LEDs America T8s
BLS isn't the only LED T8 maker specifying better light output and efficacy than DOE test have revealed. For example, LEDs America claims that its SSL T8 tubes deliver 1400 directional lumens while consuming only 14.6W. That's close to 100 lm/W efficacy. LEDs America and its sales and distribution partner Viper Networks have announced increased production of the LED-O products over the next two quarters.
The T8-retrofit market will surely continue to draw the interest of lamp makers and electrical contractors as a significant business opportunity. Moreover, as LED T8s continue to improve, the technology could deliver significant global energy savings.