When your business involves particle accelerators shooting electrons out at nearly the speed of light, gigantic supercomputer models of thermonuclear explosions and light sources a billion times brighter than the sun, reducing greenhouse gas emissions might rank low on your list of priorities.

But the U.S. Department of Energy's national laboratories have long pursued energy efficiency projects alongside their energy and defense missions since their inception during World War II. The idea is to blend resource conservation into developing cutting-edge science. The approach has been to refine how they use their fundamental resources -- indoor space, warm air, cold water and electrons. The goal is to do more with less.

Now further spurred by President Obama's 2009 executive order, the labs are formalizing how to balance these seemingly contradictory objectives: to produce national security innovations while contending with a shifting climate using revenues from a wobbly economy.

"It makes sense to smart people to [pursue energy efficiency], and we have a lot of smart people that work here," said Devin Hodge, sustainability program manager at Argonne National Laboratory outside Chicago. "Everybody wants to go to the prom with sustainability."

Under Executive Order 13514, federal agencies and divisions are required to reduce their fossil fuel consumption, their energy intensity -- energy consumed per square foot of office space -- and their emissions while acquiring energy from renewable sources and alternative fuels. The order also sets targets like requiring agencies to cut water consumption 26 percent below 2007 levels by 2020, to recycle half of all nonhazardous waste by 2015 and to ensure all federal buildings designed after 2020 achieve net-zero energy consumption by 2030.

These targets are pretty ambitious for run-of-the-mill office parks, let alone science facilities that do everything from engineering crops to designing nuclear reactors. And with new research and a strong push for inventions to pull the United States out of its current economic rut, many labs are expanding, with new machines, offices and workstations to handle their broadening mission. But by cutting back while moving forward, will the end result be to stand still?

Grappling with a $28M electricity bill

At Argonne, facility managers are pushing for sustainability with one central goal in mind: reducing the lab's contribution to climate change. "Every single goal that we have, even water reduction, amounts to energy reduction, which amounts to greenhouse gas reduction," Hodge said.

These emissions aren't limited to carbon dioxide. Sulfur hexafluoride, an anti-arcing gas used in high-voltage electronics, is used in many sections of the lab. One pound of the gas is equal to 23,900 pounds of carbon dioxide in global warming potential. Argonne used 5,500 pounds-mass of sulfur hexafluoride in 2008, the most recent data available.

According to Hodge, the lab installed equipment to control fugitive emissions of this gas in devices like circuit breakers and electron microscopes. Now it capture 99 percent of these emissions and recycles them.

The buildings that house the offices, computers and lab benches also present opportunities for energy reductions. Many were constructed in the 1940s and '50s, well before green building standards and LED lighting. "The technology was sodium vapor bulbs and incandescent lights," Hodge said. "You could change all those out now, and it's really inexpensive and they have really quick paybacks."

Several of these buildings have been modified so that heating, ventilation and air conditioning (HVAC) systems were retuned from their original specs to better deal with how the buildings are currently being used while incorporating more energy-efficient controls, motors and ductwork.

At Lawrence Livermore National Laboratory near California's San Francisco Bay Area, HVAC systems are the largest energy consumers on the facilities side, according to Noah Goldstein, scientific lead for site sustainability at Livermore. The lab sprang from an old Air Force base, and operators are also working to modernize its aging buildings, trying to chip away at its $28 million annual electricity bill.

Putting Ph.D.s on bikes

But unlike Argonne, which is under DOE's Office of Science, Livermore is run under the National Nuclear Security Administration, so its mission is focused more on national defense.

However, Goldstein said reducing emissions and energy consumption is a critical component of the lab's function. "The concept of sustainability is ingrained into our mission," he said. "The United States can exist in a low-carbon future, making it [energy] independent and secure." To this end, the lab operates and is constructing several buildings to meet the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) standards.

Using smart thermostats, Goldstein said, these buildings can more effectively handle the region's weather. "We have days where you need heating in the morning and air conditioning in the afternoon," he said.

LEED-certified buildings have also risen up at Brookhaven National Laboratory in Long Island, N.Y. "We have made tremendous gains in reducing the energy intensity of our overall usage here," said Lanny Bates, assistant laboratory director for facilities and operations at Brookhaven. The new facilities have benefits beyond lower electricity and water bills. "We can do better science in newer buildings," Bates said.

Labs are also cutting their carbon footprints by targeting how people get around their massive campuses. Brookhaven provides E-85 ethanol fuel, biodiesel and compressed natural gas for vehicles to get to and around its 5,000-acre site. Argonne has a bike sharing program to get around its sprawling 1,700 acres. Hundreds of orange and yellow bikes roam Livermore's 640-acre site, as well. The labs are also investigating strategies for carpooling and shuttling to reduce emissions from commuting. "We're doing a lot of small projects that amass to big reductions," Hodge said.

But these big reductions have to offset big energy users and even bigger facility expansions. High-Energy Mission-Specific Facilities -- the supercomputers, accelerators and colliders that are the main reason for some sites -- are scattered throughout the country. They make up a huge chunk of energy and water use at the national labs. Such devices have always been a part of the labs' mission, like the centrifuges and gas diffusers used to enrich uranium under the Manhattan Project, though now the scale is much larger.

Argonne's Advanced Photon Source (APS), for example, uses more than half the lab's electricity, consuming 150,000 megawatt-hours of electricity out of the lab's total 267,000-megawatt-hour annual usage in fiscal 2011. The ring-shaped facility spans 3,622 feet in diameter and provides the most powerful X-rays in the Western Hemisphere to more than 5,000 researchers in physics, biology and chemistry.

Bringing in still bigger machines

"That is a great machine that allows us to do some really good research for this country, but it uses a lot of electricity," Hodge said. "So our challenge is to reduce as much electricity and energy usage that won't impact our mission."

The Relativistic Heavy Ion Collider at Brookhaven, which can produce temperatures greater than 7 trillion degrees Fahrenheit, is its largest energy user, according to Mark Toscano, Brookhaven's energy manager. The collider is used to study the universe after the Big Bang.

At Livermore, half its power goes to its supercomputers, which run around the clock ready to simulate how plumes of radiation or toxins may spread from a leak to give responders a change to prepare, as they did following the March 2011 accident at the Fukushima Daiichi nuclear reactor in Japan. "Since we can no longer test nuclear materials, we simulate what nuclear explosions can be," Goldstein said. The supercomputers are also used to model climate change and weather.

On top of all this, the labs are poised to expand. The Obama administration allotted $126 million in its 2012 budget proposal to develop exascale computing, which involves calculating more than 1 quintillion floating point operations per second (flops), almost 1,000 times more powerful than some existing supercomputers. Hodge said he expects such a facility at Argonne would double the lab's energy consumption. "That's a real difficult thing when we're trying to reduce our greenhouse gas emissions that go with our electricity," he said.

Brookhaven is slated to decommission its National Synchrotron Light Source, its most popular machine, by 2015 and replace it with a $912 million facility that is 10,000 times brighter. Earlier this month, Livermore benchmarked its new supercomputer, Sequoia, at 16.32 petaflops, making it the fastest supercomputer in the world by a wide margin. The machine runs on almost 1.6 million liquid-cooled cores and consumes 7,890 kilowatts of power.

Shrinking the appetites of these hungry machines poses a unique challenge for the labs. "Those don't fit the typical energy consumption model," Hodge said. "You can't go and say, 'Hey, turn down the APS a couple notches.' It has to run at its full power."

Recycling waste heat

Nonetheless, managers at Argonne are finding ways to turn energy lemons into lemonade. "In the APS, because of that beam, we generate a decent amount of waste heat," Hodge said. "We reuse that waste heat in the buildings."

Researchers at Brookhaven schedule their usage during off-peak times and parts of the year when electricity is cheaper, running their synchrotrons and supercomputers during the winter and spring when prices are lower and scaling down over the summer. The collider runs for 20 weeks out of the year. "We cut our electrical load in half during peak summer months," Toscano said.

For Brookhaven's new light source, the main housing and its support buildings will be LEED certified. Bates said the spaces will be tuned to operate at higher temperatures so they can be cooled with ambient air.

Livermore's supercomputers are tweaked to use less energy for a given amount of processing power and are making improvements with each iteration. Sequoia uses one-third less power than Japan's K computer, now ranked second in the world. "We've gotten a hundred times more efficient," Goldstein said. "We've also reduced the space by two orders of magnitude, as well."

Facilities also need to craft ways to pay for these upgrades. "We can't simply go and spend a million dollars to put cool roofs in," Goldstein said. Since funding is allocated in Washington, D.C., and paybacks and savings don't necessarily come back to the labs, many are financing their projects internally.

"We take projects we've done in the past, and we quantify their savings," Hodge said. "We document all that and send it to our [chief financial officer's] office. During the payback period, they use the theoretical savings from that project and pay it back to us using a fund to pay for new projects."

Using these tactics, science and sustainability are no longer either-or propositions for the national labs. "If we are able to reduce the energy costs, we get more research productivity," Bates said. Though energy consumption may go up, when labs select renewable energy sources, generate electricity on-site and cut waste, overall emissions can still go down.