Summary
Tracy Dahl is passionate about developing sustainable solutions. His work as a professional motorcycle mechanic eventually led him to tinker with solar power. He and his wife have spent 25 years living off-grid. “I have forgotten what a utility bill looks like,” he said. When his mechanical expertise landed him a job as a snowmobile mechanic in the Antarctic, he saw an opportunity for renewable energy there as well.
Project
Dahl began working in polar research programs in the mid-1990s. Knowing how well solar could power his life back home, he was surprised that scientists weren’t taking greater advantage of it in the Antarctic. “Even though the wind was blowing all the time, and the sun was shining, there was very little renewable energy being used,” he said. “It became my goal to get more renewable energy into the program.” Dahl’s career as the first renewable energy expert on the Earth’s southernmost continent began. He recalls that, at first, it wasn’t an entirely welcome transition. Even with the known drawbacks of dirty, expensive diesel generation, it was predictable and familiar. Eventually, he started to win teams over by getting some small solar systems into the field.
“What really turned it around was when the researchers started coming back home saying how great it was to not deal with the dirty generators that needed frequent repair,” he said. “They wanted more renewables.” Some additional Department of Energy funding really got the ball rolling and Dahl and his colleagues were able to do some larger projects. In 2000, he was asked to join a program in the Arctic. He switched poles and continues his work there today.
Solution
Throughout the past couple of decades, Dahl has done a variety of wind and solar projects including systems with a single solar panel, charge controller and battery; vehicles with DC and AC power; chalets at research stations; and complex projects like large autonomous power and communication systems with remote-control monitoring that run lidar, radar and other research equipment in some of the harshest, most remote locations on the planet.
He works closely with researchers to fully understand their needs, then designs systems according to their requirements and constraints. Different projects demand different solutions, but over the years he’s found that Morningstar products are always up for the challenge. “Morningstar’s been around for quite a while,” he said. “I was using their charge controllers in the Antarctic in the late 90s and I’ve probably used every model that Morningstar makes at one point or another ever since,” Dahl says that Morningstar charge controllers are his go-to solution because—in addition to their price point—they can withstand the difficult, condensing environments that often take out power electronics. He’s especially fond of the controllers’ maximum power point tracking (MPPT) capability.
“In a high-altitude, low-temperature environment with reflective snow cover, the MPPT works incredibly well, providing about 20% to 25% more energy capture than pulse width modulation (PWM) controllers,” he explained. “The cold weather pushes the panel voltage way up, but that doesn’t mean anything unless you can turn it into amps through the MPPT. I have actually measured it out side by side and it’s astonishing how much better it works in these environments.”
Dahl will occasionally incorporate energy storage with absorbed glass mat or lithium iron phosphate batteries due to their greater energy density. He’s also a fan of KiloVault-brand models with internal heaters. He finds success in placing batteries in coolers within lightly insulated buildings, discovering this “in a box, in a box, in a box” approach keeps out the cold. Dahl developed a clever solution using a multi-azimuth method. By facing one solar module south, one east, and one west, he can capture energy as the sun circles the sky, particularly during high summer.
“What really turned it around was when the researchers started coming back home saying how great it was to not deal with the dirty generators that needed frequent repair,” he said. “They wanted more renewables.” Some additional Department of Energy funding really got the ball rolling and Dahl and his colleagues were able to do some larger projects. In 2000, he was asked to join a program in the Arctic. He switched poles and continues his work there today.