Ways to increase energy efficiency explored at AEDC

  • Published
  • By Patrick Ary
  • AEDC/PA
ARNOLD AIR FORCE BASE, Tenn. --  It's an unavoidable cost of doing business: in order to fulfill Arnold Engineering Development Center's mission, the base has to consume power - at times, a massive amount of it.

That's why AEDC workers are actively working to lessen the energy use and ultimately the cost of the rigorous testing that goes on in base facilities.

Engineers in AEDC's technology branch, tasked with finding projects for small businesses to invest in, recently got in touch with the Tennessee Valley Authority in an effort to find ways to decrease AEDC's energy footprint.

The AEDC group looking into new technology for Small Business Innovation Research (SBIR) topics reached out to TVA because the company has people who are always looking for new ways to save energy.

"We recognize that we're not energy experts ourselves," said SBIR committee member Will Mallory. "So we looked to TVA and got in touch with them, and they were really happy to come down here and talk with us."

Their initiative is just one of many fueled by AEDC chief technologist Dr. Edward Kraft's desire to find ways of saving energy on base.

"I started an exercise not quite a year ago and said 'OK, what are all the things we can possibly do to offset our energy costs or conserve energy?'" Dr. Kraft said. "In the initial discussions, nothing's off the table. The SBIR policy is one small subset of that."

It's a small subset that is generating a lot of ideas. SBIR assistant program manager Capt. Ashton Hainge says TVA officials are using their expertise to do more than find ways to save energy; they're trying to find energy-efficient projects that can actually be done.

The technology division's immediate focus was on what he calls the "low-hanging fruit" - ideas that give a high return on investment.

"We need more visible successes to inspire us to keep AEDC highly efficient and competitive and show what can be done when we work together," Captain Hainge said.

In the last two months, TVA officials have met several times with base workers to look at ways to save energy and money at AEDC. The big question that emerged from those meetings: How can the base harness some of the energy it expends during tests?

TVA has many industrial customers that use massive amounts of power, but AEDC is different from most because the power usage spikes to high levels during testing.

"We hang at about 20 megawatts base load here, no matter what we're doing," Captain Hainge said. "Then we have these sporadic tests in between that shoot our usage up to 300 megawatts, but they're spikes. They said when you have a spiky system like we have, you need ways of storing energy for those times that you're going to spike, like a battery."

The problem is finding a way to store that energy until the next time it's needed for an energy spike, and it's not an easy one to solve according to Daryl Williams, TVA's senior manager for clean and renewable energy. But just because it's a complex problem doesn't mean it can't be conquered.

"We don't think it's impossible," Williams said.

In fact, TVA and a third party have been working with another industrial customer in the Tennessee Valley that has large amounts of waste heat to try and find some energy harvesting solutions, Williams said. The key is finding a way to store the heat energy.

"We already know how to capture the heat and use it in a power cycle," Williams said. "The problem is what material, what mechanism, what type of ceramic, how big does it have to be to capture that waste heat through duct work, retain it in some type of material - ceramics, metals, whatever - and make it available at a lower temperature for a longer period of time. That's the trick."

There are other ways for saving energy and money that are also on the table.

Biomass energy is generated by burning biological materials. Oak Ridge National Laboratory (ORNL) is in the process of bringing online a new biomass steam plant consisting of a gasification boiler that will use wood chips as fuel.

AEDC and TVA representatives recently paid a visit to ORNL to learn more about it and say the technology could be applied at AEDC because of the vast amount of land.

"You could grow various energy crops that are dedicated for energy production; things like switchgrass or miscanthus," Williams said. "You can grow these dedicated crops for base heating or small power generation."

Solar power is another option, Williams said, because many base roofs are flat and could have panels easily installed to generate power. He said the cost of solar power is going down and is projected to be comparable or equal to coal in the next 10 to 15 years.

But again, the research the SBIR committee is putting in is just one part of Dr. Kraft's strategy for finding ways to rein in AEDC's energy costs.

"They're looking at new technologies no one's thought about, and that's pretty exciting on their end," Dr. Kraft said. "I like to have those great ideas, but just good solid no-kidding engineering would be helpful too."

To that end, Dr. Kraft says ATA engineers are analyzing potential business cases right now to see if there are some that warrant further exploration. And he says the company has already done a good job coming up with ways to save energy in AEDC's day-to-day operations.

"The ATA engineers are very creative guys, and they've figured out how to do things already that don't even cost us anything," Dr. Kraft said. "They just do it. Just looking at our day-to-day processes, they've come up with ways to save energy."

ATA Deputy General Manager Steve Pearson says every design that is produced for an investment project on base is geared toward using less energy and being less expensive to operate. Old air compressors in the base's Engine Test Facility and von Kármán Gas Dynamics Facility were replaced with a more energy-efficient system.

Another example is the Turbine Engine Dry Air Capability (TEDAC) project that will provide dry air for altitude testing in AEDC's Aeropropulsion Systems Test Facility (ASTF). It is scheduled to enter its second phase of construction later this year, and when completed it could provide up to $1 million in energy savings depending on the amount of testing conducted in ASTF.

ATA has also saved energy through process changes and making sure employees are aware of how they can save energy, Pearson said. Those initiatives have saved money and energy without significant investments.

Looking to the future, Pearson says everyone involved realizes saving energy is important and will only become more so, thanks to oil-producing countries with potentially unstable governments and developing nations like India and China that will continue to consume more energy.

"The thing that puts us out of business is probably not going to be budgets," Pearson said. "It's more likely to be the cost of energy. We use a lot of it and if we don't purchase at a reasonable price, the cost to our customers may exceed a threshold they are willing to pay."

In addition to Dr. Kraft and his team's work looking for new initiatives, Pearson said ATA is planning an energy conference in the summer that would bring together TVA, the Department of Energy, ORNL, UTSI and UT-Knoxville to start a dialogue on energy conservation.

"It's pretty exciting, because we have great opportunities," Pearson said. "Keeping our center strong and serving our customers is important to us. We're going to be successful."

The brainstorming collaboration between AEDC, TVA and other possible partners is in the early stages, but everyone involved agrees that there is potential for savings and increased energy efficiency at AEDC.

"It hasn't really materialized, but we definitely are further than we were a month ago," Mallory said. "We're evolving these relationships and everyone seems very receptive."

As for Dr. Kraft, he's ready to hit the road to pitch an idea, hopefully by mid-summer.

"I'm hoping in the next three or four months we have one of those tigers by the tail that we can actually chase some resources with," he said. "We have a lot of work ahead of us, but I'm enthused by the enthusiasm people have out there. And people are thinking, so we're starting to come up with good ideas."