During a special webcast on April 7, Hughes provided a detailed review of one full year’s worth of data demonstrating that the total light management system in the building is exceeding the previous benchmark of 70 percent. Hughes said total light management “represents the single greatest opportunity for energy savings in commercial buildings, whether retrofit or new construction projects.”
With help from the Lawrence Berkeley National Laboratory, Hughes began his presentation with a myriad of statistics about national energy usage, including the fact that buildings account for 71 percent of electricity consumption in the United States and that lighting is the single greatest energy user in commercial buildings.
Hughes said the cost savings yielded by the total light management system adds up to $30,000 per year per floor for the floors where it has been installed. This equates to approximately $1 per square foot per year. He attributed the cost savings to a significant reduction in lighting and cooling load.
Hughes discussed the additional value-add of increased productivity resulting from the improved lighting environment. Assuming a 1% increase in productivity (a conservative estimate), Hughes asserted that the Quantum system paid for itself in less than a year. He also emphasized that this value-add goes on year after year.
The energy consultant stratified his data in a number of different ways, including season by season to take into account differing conditions of natural light and heat.
Last year, Hughes was widely quoted for announcing, “We designed our building to use 1.28 watts per square foot of lighting power. With Quantum™, it’s using only 0.38–that’s 70 percent less.”
During the webcast, he unveiled data showing that the building’s Quantum total light management system equaled or surpassed that figure in each of the past four seasons:
Winter (2008-09): 0.37 W/sq. ft.
Fall (2008): 0.37 W/sq. ft.
Summer (2008) 0.33 W/sq. ft.
Spring (2008) 0.38 W/sq. ft.
The seasonal data reflects a yearly lighting energy savings of 72 percent.
To view the webcast or for more information please visit www.lutron.com/nyt.