Harvard College Library News: News from around the libraries

HCL Lighting Changes Save Energy

sustainability lighting

Lighting changes throughout the libraries managed by Harvard College Library Operations, including the installation of compact fluorescent lightbulbs, have
helped HCL add to Harvard's sustainability efforts

December 15, 2009 – In recent months, several lights in libraries managed by HCL Operations have been turned off and occupancy sensors installed in other areas, helping the library not only contribute to the green efforts, but save some green as well. The projects, part of HCL’s commitment to sustainability, have helped conserve thousands of watts of electricity, and saved thousands of dollars in utility costs.

“We have done a lot to conserve electricity,” said HCL Operations Director Paul Bellenoit, who helped lead the push for improved energy efficiency throughout the libraries. “We installed occupancy sensors in offices in Houghton, Lamont Pusey and Widener. We have also reduced lighting in some areas, though the reductions won’t affect patrons.”

Related Links


  • Facebook
  • Twitter

Initiated by Bellenoit and Associate Librarian Rebecca Graham, Harvard College Library Sector leaders for the University Green House Gas Reduction Program, the electrical projects are one of a handful of ways the libraries are working to help Harvard meet its sustainability goals, which include a 30 percent reduction in greenhouse gas emissions from 2006 levels by 2016, developing and applying sustainability principles, and implementing green building practices. Operations staff in recent months also fine-tuned the operation of the HVAC systems to reflect the operating hours of the libraries, replaced more than two dozen bottled-water coolers with filtered water dispensers, installed water-conserving bathroom fixtures and even replaced older exit signs with power-saving LED signs.

Though a number of occupancy sensors were added to parts of Widener Library several years ago as part of the library’s renovation, HCL Operations this year added 130 additional sensors in offices in Widener, Lamont and Pusey, each of which results in an estimated 20 percent power reduction per room, said Andy Laplume, Assistant Director for Project/Building Systems Management.

“If you leave your office for more than 30 minutes, the sensor will shut the lights off automatically,” Laplume said. “For many people, that could result in saving two or three hours of electricity every day. It may not be a big savings per room, but when those savings are multiplied by the 130 sensors we have in place, it adds up.”

In certain library areas, such as the microfilm storage room in Widener Library, the sensors are saving even more power.

In addition to the savings, the library will receive several thousand dollars in rebates from NSTAR, as part of the utility’s program to offer incentives for energy-efficiency projects.

In other areas, savings have come from simply turning lights off.

As an example, Laplume pointed to the carrels in the Widener stacks. Every carrel includes a light fixture which points upward and acts as indirect lighting. Until recently, each of the nearly 300 lights was turned on daily at 8 a.m. and left on until closing time, consuming nearly 19,000 watts of electricity per hour. Tests, however, found that the lights have almost no effect on the lighting conditions around the carrels during the day.

“You get plenty of natural light because the carrels have windows,” Laplume said. “Plus, you have the aisle lights and the main corridor lights in the stacks, as well as a desk lamp which can be turned on and off. As a test, we shut off a section of those lights, and you couldn’t tell the difference, so we shut them all off. Now, they only come on at night, and the wattage savings is huge.”

Simply reducing the hours the light are on, Laplume said, cut the electricity consumed by the lights from more than 100,000 kilowatt hours to just over 30,000 kilowatt hours per year, saving the library more than $10,000 in annual electric bills.

Similar changes have also been made in the Loker, Phillips and Stacks reading rooms, with similar savings.

In the Loker Reading Room, 82 lights that circle the ceiling have been turned off, resulting in thousands in savings. More than a dozen similar accent lights, which threw light on the windows above the bookcases in the Phillips and Stacks reading rooms, have also been turned off, producing several thousand more in savings.

Also turned off in the Phillips and Stacks reading rooms are 68 spotlights mounted in the rafters. While not the most expensive in terms of power consumption, the hard-to-reach spotlights were among the priciest in the Library to replace, with annual maintenance costs running nearly $10,000.

“To replace them, we’d have to spend an entire night, with workers on lifts changing all the bulbs in one room, then moving and changing all the bulbs in another,” Laplume said. “Ultimately, though, you could put a light meter on a table, turn those lights on and off, and it would make no difference.”

In June, workers replaced the ring of 14 incandescent bulbs which lit the main stairwell ceiling cove in Houghton Library with cold cathode lighting.

“The new lighting should last for years, and it’s much more efficient,” Laplume said. “The real benefit, however, is in maintenance. Just to change those lights, cost more than $1,500, because we had to erect scaffolding out over the stairs, and we would normally have to replace those lights two or three times a year.”

Other minor changes include turning off half the lights in the tunnel between Widener and Lamont libraries, and replacing incandescent bulbs with energy-efficient compact fluorescent bulbs whenever possible.

Though HCL’s accomplishments in the past are great, Bellenoit said each day brings new challenges and opportunities to save energy, and that he and his staff are always on the lookout for new ways to reduce energy consumption and continue to contribute to Harvard’s Greenhouse Gas Reduction Program.