BREMERTON, Wash. - Navy contractors are drilling for heat.
Though the ground doesn't warm up the closer you get to the bottom of 350-foot-deep holes, 48 of them will provide enough energy to keep a 264-room dormitory cozy.
Washington Patriot Construction of Gig Harbor began work this week on a $2.6 million ground source heat pump system for Naval Base Kitsap's Bachelor Enlisted Quarters (BEQ) Building 1044. It's part of a $13.8 million project that includes another geothermal system and renovations to 168-room BEQ Building 1001.
The new Building 1044 system will save the Navy $266,000 a year in energy costs and pay for itself in nine to 10 years, said Paul Songe-Moller, energy manager with Naval Facilities Engineering Command Northwest.
A sonic drill rig -- of the type used for digging water wells -- is noisily vibrating, rotating and punching open 6-inch diameter holes. One-inch plastic pipe will be run to the bottom, whip a U-turn, return to the top and continue to the next hole. Antifreeze will circulate through the 35,000 feet of buried pipe.
The ground, whether four feet down or 350, is about 55 degrees. Check your basement and that's probably the temperature there, said Mark Bennett, NAVFAC engineering manager who helped design the project. You have to go down thousands of feet before it heats up.
During winter, the ground will keep the liquid in the pipes warmer than the outside air, and it will be used to warm the inside air. In the summer, it will be colder than the outside air, and be used to cool the buildings.
"Geothermal is misleading to a lot of people," Bennett said. "A geyser brings up thermal energy. This is not doing that."
Eight-story Building 1044 opened in 2004 with a steam heating system. It'll be retained as a backup and for frigid weather, when a heat pump is less effective. The work will be completed in October.
"We'll try to use each technology to its best advantage," Songe-Moller said.
Nearby, 17-year-old Building 1001 will get energy-saving renovations such as low-flow toilets and sink and shower fixtures. Old doors, sinks and counters will be donated to the Habitat for Humanity store. Everything else will be recycled.
"We're not gutting the whole building," said Zerah Florance, quality control manager for Washington Patriot. "We're giving it a face lift, modernizing it to make it a more comfortable place for the sailors to come home to."
Building 1001 will be completed in March.
The Navy's goal is to reduce energy consumption 3 percent per year, and 30 percent from a 2003 baseline.
The Navy installed a similar geothermal heat pump system at Naval Undersea Warfare Center Division Keyport a couple years ago as part of a $15.9 million energy-saving project. The work earned the base a 2012 Federal Energy and Water Management Award. Keyport reduced energy use by more than 30 percent the first year, translating to $2 million in savings.