TOKYO — Long before Japan’s nuclear crisis, U.S. bases were aggressively cutting energy consumption in an effort to become net zero users of Japanese electricity.
Over the past few years, bases have been upgrading heating and air conditioning systems and installing energy-efficient lighting, insulation, double-glazed glass and solar water heaters as part of a military-wide energy efficiency drive. A 2007 federal law requires the military to cut energy intensity — the amount of energy consumed for every 1,000 square feet of indoor space — by 3 percent each year.
Since then, Army and Navy facilities in Japan have reduced their energy intensity by nearly a third. As a result, military officials say the bases are in a good position to help their neighbors cope with expected summer electricity shortages and potential blackouts stemming from earthquake damage to the Fukushima Dai-ichi nuclear power station.
This summer, military officials are encouraging Japan base residents to cut electricity consumption by as much as 30 percent to lessen the strain on local power grids, but they continue to have their eyes on future projects.
U.S. Army Garrison Japan has ordered base energy officials to identify 25 projects each year that include energy efficiency improvements.
More than 1 million kilowatt hours of electricity will be saved each year because of upgrades to Army facilities in Japan during the past 12 months, according to Felix Mariani, who heads the Directorate of Public Works Environmental Division at Camp Zama.
In the coming year, new energy-efficient lighting at the Camp Zama Post Exchange will cut the garrison’s annual electricity bill by $64,000, while another initiative — installing timers on air conditioners — will save $187,000 a year, he said.
At Yokosuka Naval Base, a gas-fired 39-megawatt co-generation power plant that began operating in November 2008 has also led to major energy savings, Naval Facilities Engineering Command Far East Public Affairs spokesman Ronald Inmann said.
Last year, the Navy executed 23 energy-saving projects worth $2.8 million in the Japan region that will save an estimated $887,000 worth of electricity annually, he said.
This summer, workers will install $3.5 million worth of solar panels — enough to power 200 homes — on the roof of the Yokosuka commissary, according to Tom Bowden, Commander Fleet Activities Yokosuka energy manager.
To meet its energy savings goals, the Air Force sets aside $200 million each year for energy-efficiency initiatives, according to Yokota Air Base energy manager Chris Cook.
“Every dollar that we use to pay for energy could have been used to keep a C-130 (cargo aircraft) in the air,” he said. “When we talk about reducing our energy we are talking about more mission capability.”
A $5.6 million project this year to replace “chillers” — parts of the base air conditioning system that cool water — will cut Yokota’s energy intensity by 4 percent and save roughly $1.2 million annually, he said.
All of the projects on the air base have to be economically viable, Cook said.
“We don’t take $2 million to save $500 worth of energy,” he said. “If we spend $2 million we are going to save $500,000 a year.”
Longer-term projects could include a new waste-burning power plant at Yokota, wind turbines at Tama Hills and Yokosuka and solar panels on the roofs of buildings at Army posts in Japan.
The Army estimates it could generate one megawatt of electricity, or 15 percent of the energy it uses on its Japan bases, using rooftop solar panels, Mariani said. The Army has also considered building a trash-burning power plant at Camp Zama, although a better option might involve sending the waste to a similar facility in nearby Sagamihara City, he said.
Ironically, the military may end up powering its bases with the same geothermal energy source that caused the March earthquake.
According to Mariani, the Army and the U.S. Department of Energy have determined that the most cost-effective option for renewable energy on Army posts in Japan is $31 million worth of geothermal power projects that could be built as soon as 2015.