Applied 'green' research teaches cadets about ins, outs of renewable energy

  • Published
  • By Don Branum
  • Air Force Academy Public Affairs
U.S. AIR FORCE ACADEMY, Colo. --  A Defense Department-funded initiative in the Electrical and Computer Engineering Department here offers cadets a chance to get their hands dirty by making the environment a little cleaner.

The program, which has received $270,000 since 2009 from the Office of the Assistant Secretary of Defense for Research and Engineering, is designed to teach cadets about renewable energy, including its benefits and limiting factors and how best to employ it in a field environment.

Last year's capstone computer engineering project involved the installation of a mobile solar power system, which currently sits on the roof of Fairchild Hall.

"It was built as a prototype of a mobile system," said Al Mundy, an electrical engineering instructor. "It's not mobile at the moment: It's lacking the wheels. But it could be moved if we wanted it to be."

The system's energy input is small compared to Fairchild Hall's overall needs -- it's the data that holds real value, said Mundy.

"All of that data is brought back into the lab," he said. "Cadets can see what happens when it snows or when light is shining across panels."

The solar panel formed part of this year's capstone project, which involves a small, quiet all-terrain vehicle donated from the special operations community. Solar energy is a good alternative to a diesel generator for both noise and cost reasons, Mundy said.

"Diesel is noisy and very expensive in a deployed environment, and it requires a lot of maintenance," he said. "Here, it's a closed system. The only thing we have to maintain is keeping the brakes clean."

The vehicle presents challenges of its own as well: The Academy received it in what one might call "well-loved" condition. Cadets had to familiarize themselves with the vehicle, even reverse engineering parts of it when they found the quality of existing engineering documents lacking, Mundy said.

"One of the things we teach is that good documentation is important," he said. "Now the cadets are seeing what happens when that's not the case."

Renewable energy isn't always available: The sun doesn't shine 24 hours a day, and it's not always windy enough to power a wind turbine, said Lt. Col. Andrew Laffely, the Electrical and Computer Engineering Department's director of plans and programs. But even with drawbacks, the DOD has compelling reasons to look into alternative energy sources.

"The cost of fuel is very expensive in Afghanistan and Iraq," in large part because transporting the fuel to bases costs a lot of money and carries a high risk, he said. "Even little things we can do make a big difference in terms of how we can operate. This helps our (soon-to-be) lieutenants be realistic in terms of what's achievable with renewable energy."

The vehicle is not designed for long-range operations, so the power generation system will have to be portable as well. That, Mundy said, will be the focus of next year's capstone project.

"Teams will build a trailer so the vehicle has a completely mobile type of storage," he said. "The trailer can provide power to whoever needs it."

In order to complete the project, next year's capstone class will have to get smart about smart grids. The first step, Mundy explained, is setting up a microgrid.

"So the cadets need to find out, how much solar area or how big a wind turbine it would take to charge the vehicle's batteries," he said. "If we can do that on a standalone basis, that builds a microgrid."

Microgrids allow electrical engineers to manage power on a small level: in this case, a single vehicle or a small fleet. A cadet-operated microgrid would need to balance the supply of renewable energy with demand from the vehicles or from other energy consumers on base. The engineers can then network their microgrid with the base's main power grids or with other microgrids on base to create a smart grid, which allows the smaller power networks to share energy.

"For a smart grid, you have to ask, 'Can I plug it into the main power grid?' It's about the communication of energy data," Mundy said.

At project's end, Laffely said, cadets come away with more than just a better understanding of renewable energy.

"I was deployed last year, but the year before that, the capstone project was a wind turbine generator for a Humvee, and the cadets had a ball," Laffely said. "Hands-on learning and experimentation is really valuable. Cadets this year have gotten their hands dirty and really taken ownership, and that's what I want to see them do -- get into the practice of being computer, electrical or system engineers."