WASHINGTON (Army News Service, July 31, 2012) -- The Army's energy chief continues to press home the need for energy efficiency saying that stewardship of water and power resources begins with behavioral changes by Soldiers, from the top down, not solely with investments in technologies and new equipment."Now to put it all in perspective, the Department of Defense makes up about 80 percent of the federal government's energy use," said Katherine Hammack, assistant secretary of the Army for installations, energy and environment, before members of the Association of the U.S. Army. "Of that, the Army is the largest facility energy user, electric energy user and that's because we have the most bases and most buildings."Hammack said the Army represents 20 percent of DOD's total energy use. She also said that in 2011, Army energy expenses totaled $5 billion, which is a $1 billion increase over the prior year.Some of that increase is due to things outside Army control, Hammack said. Included in that is the volatility of the fuels market."The fact is, costs are something we cannot control, but we can control our use," Hammack said. "Energy secure installations must be highly efficient with reduced electrical loads made possible through energy measures and behavioral change."Hammack cited how in the wake of the March 2011 tsunami in Japan, all military bases and major industries that run largely off nuclear power plants were asked to reduce their energy consumption by 15 percent. She said that within two weeks and through behavioral change, Army bases had reduced their energy consumption 18 percent and by summer's end, consumption was down by 23 percent.While Soldiers need to have situational awareness about their energy usage, both on and off post, the secretary said installation energy security will also mean developing new technologies and renewable energy sources to go with energy efficiency."An energy-secure installation is one that's able to do its mission when all else in the surrounding area might go down," the secretary said. "That requires smart investment in renewable energy and energy efficiency because the lowest cost unit of energy is that unit you don't use."Installations must be equipped with a smart grid that's able to prioritize and match loads with supply which will also allow installations to move power from generator to generator or building to building, she said.One example, she said, was Fort Irwin, which had partnered with the local utility. To curtail the likelihood of a brown-out or black-out situation, the utility will get in touch with the 642,000-acre California installation and request the post cut energy consumption by 25 percent."The installation can do that and they know how and have a protocol to do that," Hammack said. "Not only have they reduced their costs, the utility rebates them and last year about $400,000 was rebated because they were able to prioritize, match loads and drop loads in response to the market or utility request."Hammack said base load power like that at Dugway Proving Ground in Utah rely on generators powered by diesel, "but where it should come from is renewable energy sources -- geothermal, solar, wind, biomass from wood chips."Hammack said there are even more opportunities that the Army is exploring.SOLDIER POWER"Soldier power" refers to the power a dismounted Soldier requires in the field. Hammack said that as the Army loads up Soldiers with new technology, they are also being loaded up with heavy batteries to provide the needed power. Those batteries, she said, mean increased weight."We're working on ways that we can distribute power and manage recharging -- some of those solutions are solar-based rechargers and some of them are fuel cell rechargers which will give the Soldier flexibility and adaptability," she said.She said as the Army modernizes, helicopter engine designs are being looked at to see how efficiently they burn fuel."A new drop-in engine in the works is going to have 25 percent less fuel consumption, yet double the horsepower and it fits into the same area as the current engine," she said. "That means this helicopter will be able to increase its payload and travel a further distance on the same volume of fuel, that's about energy efficiency and increasing mission effectiveness."Hammack said the Army was also working on how to reduce water consumption in conjunction with reducing fuel and electrical consumption. She said that 61 percent of the U.S. is under drought conditions, most of that in the southern half of the country, where most Army installations are located which makes those communities the largest water users.