A simple change being made to military camps in Afghanistan will save enough energy to take an estimated 7,900 fuel trucks off the road over the next year, an Army officer in charge of battlefield energy said this week.
By networking battlefield generators together in 28 basic "minigrids," the Army can use diesel-fed generators more efficiently, taking approximately 545 units offline, said Col. Tim Hill, who directs the Army's operational energy program and oversees basing in Iraq and Afghanistan. Twenty-two of those mini-grids have been built and at least six are planned for this year, according to Hill.
The changes come as military brass increasingly recognize the combat dangers of trucking diesel to far-flung camps and the financial necessity of cutting what was last year a $15 billion fuel bill.
Although the military has not been consistently collecting data on combat fuel consumption, all signs point toward generators as a major energy sink, Assistant Secretary of Defense for Operational Energy Sharon Burke said in June as she released the Defense Department's first battlefield energy strategy (Greenwire, June 15). Such generators provide electricity for everything from air conditioners to computer systems at battlefield camps.
In part because bases need to be able to grow or shrink as troops are moved in and out, camps in Afghanistan were designed with generators attached to each building, regardless of how much energy that building used. Even if two buildings with low energy needs sat directly next to each other, they each had their own generators. Since units operate most efficiently at peak, this created massive waste.
"Part of our issue is we haven't been doing the master planning at any of our forward operating bases," Hill said. "It's been ad hoc, at best."
Building even a crude electrical distribution grid to link generators allows them to share loads and be run more efficiently, he said.
Hill described the systems going in right now as little more than "a wire connecting the generators." Even greater savings will come from the cutting-edge intelligent microgrid systems being tested now, he said.
Such systems, with some capabilities similar to those of a civilian smart grid, are being designed to allow renewable sources to be fed in, energy demands to be prioritized and buildings to be monitored for when unused systems can be shut off.
"We're building an intelligent system that is dynamically monitoring the status of the grid at all times and then making the decisions to either shed or start up sources and either shed or start up loads," said Paul Marks, a senior manager at Lockheed Martin, which has contracts to build battlefield microgrids for the Air Force and Army.
To tackle the ever-changing nature of military camps, battlefield microgrid systems are designed to be able to grow and shrink easily, a quality called "plug and play" by the industry.
If the military decides systems like these are safe and effective, they could cut energy use even more, Marks and Hill say. In demonstrations, the system Lockheed Martin tested for the Army cut fuel use by 30 percent, according to Marks.
To a Pentagon that is facing steep budget cuts and sustained violence in Afghanistan, that poses a rare bit of good news.