The multi-million dollar fighter jets that roar over the local tennis court where I coach the high school team is a daily reminder that Fairbanks is home to one of the most strategically important Air Force bases in the world. And now, Eielson Air Force Base is about to make history on a very different front — testing a first-of-its-kind nuclear microreactor.

Closing the Gap is hosted by Gwen Holdmann, edited by Jennifer Pemberton, and produced by Tony Williams.

Back in 2019, Congress directed the Department of Defense to find a site and pilot a small nuclear reactor to enhance energy resilience at military installations. That site is Eielson Air Force Base near Fairbanks, Alaska. Recently the Air Force named a developer for the reactor, so we’re revisiting the story we told back in Episode 5. In future episodes you’ll hear directly from the key people moving the project forward—both the technical lead for the Air Force and the senior commander guiding its integration on the ground. For now, we’re sharing episode 5 with you as a refresher.

Water is 800 times denser than air and when large volumes start moving in a single direction with force and purpose, it becomes virtually unstoppable—whether at sea or on land. And that force represents an opportunity—to harness the power of water in a way that’s different from conventional hydropower. Instead of relying on elevation and gravity, we can capture energy directly from the flow itself. Afterall, the tides are pulled by the moon, creating a rhythm that has been in motion since long before fossil fuels were even imaginable. It’s not just renewable—it’s perpetual. Today on the show -- tidal energy in many different forms.

Closing the Gap is hosted by Gwen Holdmann. Jennifer Pemberton is our editor. Liz Smith and Tony Williams produced this episode. Music is from Bluedot Sessions. Special thanks to David Lane at Neuralsurfer, who let us use his wonderful recording of Edgar Allen Poe’s “A Descent Into The Maelstrom”.

Hydropower comes in many forms, though most people still associate it with big dams. In the heyday of dam building, projects like Grand Coulee Dam and Boulder Dam in the American West were monumental efforts. These were some of the most ambitious and costly construction projects ever undertaken. Back then, we didn’t fully understand how dams could disrupt ecosystems—blocking fish passage, altering sediment flow, and changing entire river systems. But now we do, and as a result, large dams have fallen out of favor in many places. And where the U.S. was once the leader in large scale hydropower, we’re now removing more dams than we’re building.

Today, the biggest obstacles to constructing new hydroelectric projects in the U.S. aren’t just environmental—they’re economic and regulatory. Escalating construction costs and complex permitting processes have significantly slowed the pace of development. But hydropower is a very site-specific technology—and there are plenty of ways to make it more environmentally friendly. In Alaska, for example, we have dozens of what are called “run-of-river” hydro systems. These projects harness the natural flow of water to generate electricity, often without the need for large dams or reservoirs—and without blocking fish passage, which is a big deal in a state where salmon are central to both ecosystems and communities.


Closing the Gap is hosted by Gwen Holdmann and edited by Jennifer Pemberton. This episode was produced by Tony Williams. Music is from Blue Dot Sessions.

We started our series on solar energy at a small scale. This time, we are going big. The Al Kharsaah Solar Plant in Qatar is one of the largest solar farms in the world—capable, at least in theory, of producing enough power to meet the entire demand of the Railbelt electrical grid in Alaska, which serves about half a million residents. But even though Al Kharsaah is large, it’s far from the largest. When Gwen was there last year, it was in the top 20 largest projects in the world. Today, it doesn’t even make the top 30 anymore.

In this episode, we’re going to take a closer look at solar at scale—exploring the limits to scaling up this seemingly unlimited energy source, and the innovations underway today that could define what the solar industry looks like in the future - both in solar photovoltaics like in Qatar, as well as concentrating solar thermal.

Closing the Gap is hosted by Gwen Holdmann and edited by Jennifer Pemberton. This episode was produced by Liz Smith and Tony Williams. Music is from Blue Dot Sessions.

This is the first episode in a series about solar energy, and we're starting really small. In Germany, Gwen learned about these compact personal solar kits you can install yourself -- right out of the box. There, they call it balkonkraftwerk, or balcony solar. Of course she had to buy one when she got back from Europe and try it out on her roof in Fairbanks.

But is the grid ready for this kind of DIY power generation?

Closing the Gap is hosted by Gwen Holdmann and edited by Jennifer Pemberton. This episode was produced by Liz Smith. Music is from Blue Dot Sessions.

A look at the extreme edges of geothermal energy. We'll start with the super hot -- actual liquid magma -- chatting with a couple of visionary Icelanders that have some big ideas about the future of geothermal.

Closing the Gap is hosted by Gwen Holdmann and edited by Jennifer Pemberton. This episode was produced by Tony Williams. Music is from Blue Dot Sessions.