Summer Energy Savings Much Higher Than Expected; Thermal Energy Storage Unit Ready for Operation

California State University San Marcos saved more than 338 megawatt hours of electricity by shifting to a four-day, ten-hour per day work-week during June, July and August, officials have announced. Tom Blair, director of facility services at the campus, said the savings "exceeded our most optimistic estimates." A megawatt hour is approximately enough energy to power 1,000 homes for one hour.

During the ten-week summer schedule, which ran from June 11 to August 17, Blair said the campus was able to close all but one floor of one building on Fridays and Saturdays, resulting in savings far in excess of the five megawatts per day Blair estimated before the program began. "I was a little surprised at what we could save," Blair admitted. "I thought the campus was already pretty efficient."

Summer 2001 was a trial run, testing how a special schedule might work for next year, Blair said. In 2002, the campus will be operating under a new contract with its major energy supplier, Enron, and is expected to be paying higher prices. In addition, two new campus buildings will be completed and in operation. Both the new Science Hall II and the Arts Building have high energy requirements. "We anticipate significant load increases," he predicted.

The summer schedule was part of a conservation program that also involved raising temperatures in campus buildings and reducing energy use for lighting and office equipment. Other savings came from reconfiguring the cooling system within campus buildings, Blair said. The changes included changes to pump systems and control valves that provide more consistent cooling. However, Blair reminded that "I can deliver the cooling more efficiently, but I'm not able to cool it any more." State regulations require that buildings be cooled to no less than 78 degrees and heated to no more than 68 degrees.

Another significant factor expected to conserve energy and save the campus money is the Thermal Energy Storage unit, which has been completed and is expected to go into service within a week, Blair said. The unit holds 1.6 million gallons of water that is chilled overnight and used to cool campus buildings during the day. By cooling the water at night, when energy use is low and kilowatts cost less, the campus saves money. "We anticipate a savings of about $170,000 each year," according to Blair. The $875,000 project was funded by a grant from the California Public Utilities Commission.