School excels in lighting controls

When Sidwell Friends School in Washington, D.C., upgraded its Middle School building, the administration decided that in order to live up to the school's Quaker ideal of environmental stewardship, the building would be transformed into a $21 million LEED Platinum certified facility. Sidwell was able to attain that rating due to a host of sustainable design features, including the EcoSystem lig...

By Consulting Specifying Engineer Staff June 1, 2008

When Sidwell Friends School in Washington, D.C., upgraded its Middle School building, the administration decided that in order to live up to the school’s Quaker ideal of environmental stewardship, the building would be transformed into a $21 million LEED Platinum certified facility. Sidwell was able to attain that rating due to a host of sustainable design features, including the EcoSystem lighting control solution from Lutron, Coopersburg, Pa.

As the facility manager, Steve Sawyer was given an additional mandate: He was told the Middle School building (grades 5—8), built in 1950, must set an example for environmental consciousness, exceeding the eco-friendly standard of other secondary schools in the country.

Sidwell Friends School is the first secondary school to receive the LEED Platinum designation and the first structure of any type to achieve that certification in the District of Columbia. Ground was broken in June 2005 and the project was completed in September 2006.

The project was a combination of renovation (37,000 sq. ft) and addition (39,000 sq. ft). It incorporates many sustainable lighting design features, including:

  • Lutron’s EcoSystem lighting control solution. Installed throughout the building, the controls provide energy-efficient fluorescent lighting, integrating daylight sensors, occupancy sensors, and dimming ballasts.

  • Light shelf. Installed into the fa%%CBOTTMDT%%ade, the shelf transmits daylight deep into the building while shading the corridors from direct sun.

  • Western red cedar cladding, suncreens, and high-performance windows. Exterior walls of the addition and third floor of the existing building make use of these features.

  • Photovoltaic panels. These generate 5% of the overall building’s electrical load.

On average, lighting accounts for about 55% of an educational facility’s electricity use, according to the U.S. Energy Information Administration. Lutron maintains that typically the Eco-System lighting system can cut a building’s lighting energy use as much as 60%, but Michael Saxenian, Sidwell’s assistant head of school and CFO said that, “overall, with our more efficient lighting system, better use of daylight, and the resulting reduction in air conditioning load, the school expects to reduce total energy use associated with lighting by 92%. Because of that, EcoSystem is a core component of Sidwell Friends School’s strategy of using lifecycle payback to finance more efficient energy systems.” Representatives at the school said the model has not been measured since the school’s opening to gauge the prediction and actual performance.

The EcoSystem lighting control solution senses changes in lighting needs based on the amount of natural light entering the building throughout the day, and reacts dynamically to those changes by modifying the learning environment in ways intended to improve productivity and reduce energy costs. The connection between a building and the productivity of its occupants has been gaining acceptance through numerous studies dating back to the 1920s.

Sidwell officials say the installation of Lutron’s EcoSystem lighting control solution was part of a larger strategy to achieve student productivity gains from improved exterior lighting.

Sawyer said EcoSystem’s personal control flexibility—what he calls its “user-adjustability”—has been a popular feature in the school. “Teachers have a full range of choices when it comes to overall lighting levels and the use of uplighting or downlighting,” Sawyer said. “If the teachers are using a smartboard or a projector, the students have no problem seeing the information. If the students are at a computer, the lighting level is easily adjusted so there’s no glare. It really helps create a classroom environment that’s most conducive to learning.”

The building’s “report card” bears impressive numbers: Lighting energy consumption is expected to be cut by 92%, and overall energy use has been reduced by 55%.

Information provided by Lutron, Coopersburg, Pa.

AT A GLANCE

Engineers from Bruce E. Brooks & Assocs., Philadelphia, installed Lutron’s EcoSystem lighting control solution at Sidwell Friends School.

EcoSystem reacts to natural daylight entering the building using environmental sensors, dimming ballasts, and controls. The system integrates daylight harvesting, occupant sensing, tuning, and personal override controls.

EcoSystem also includes plug-and-play components that communicate via lowvoltage wires. As building needs change, EcoSystem may be reprogrammed without recircuiting.

EcoSystem typically reduces a building’s lighting energy use and costs by 60%.