Closing the Gap with Gwen Holdmann

Join host Gwen Holdmann for Closing the Gap: stories from the front lines of the global energy transition, from our front row seat from right here in Alaska.

The Last Coal Mine in Svalbard 12/20/2025

The Last Coal Mine in Svalbard Norway is determined to move away from coal and other fossil fuels entirely, but the town of Longyearbyen in the Arctic outpost of Svalbard is literally built around coal and has identified strongly as a coal town for more than 100 years. This year, the last coal mine in Longyearbyen shut down — not because they ran out of coal, but because the country is deeply committed to trying something else, even if they haven't totally figured out what that something else is yet. Closing the Gap is hosted by Gwen Holdmann. Tony Williams is our producer and engineer. Jennifer Pemberton is our writer and editor. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/39479245

Passive Cooling 10/29/2025

Passive Cooling On this podcast, we spend a lot of time talking about electricity — how to generate it, store it, and use less of it. But the truth is, the bigger share of our energy use often goes to heating and cooling — the invisible comfort systems that keep us alive in the places we choose to live. Humans are unusual that way. Most species adapt to their environment. We do the opposite — we adapt the environment to suit us. It’s how we survive in deserts and tundra, in glass towers and remote villages. Today on the show, we’re talking about passive cooling. We bring you three stories of designs that take advantage of natural temperature differences instead of using up a bunch of energy just to make something cold. Closing the Gap is hosted by Gwen Holdmann. Tony Williams is our producer and engineer. Jennifer Pemberton is our writer and editor. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/38826210

Trash is Treasure 10/06/2025

Trash is Treasure Waste-to-energy systems kill two birds with one stone: they deal with garbage and produce power at the same time. Copenhill in Denmark has been called the coolest power plant in the world, and it’s hard to argue with that. It’s a place where you can ski down the roof, climb up the side, and then grab coffee under the smokestack — all while the building generates heat and energy for the city. At least one Alaskan community thinks Copenhagen might hold the answer for its energy and waste problems — and that’s exactly where this episode takes us. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/38487335

A Nuclear Reactor for Alaska's F-35s 08/20/2025

A Nuclear Reactor for Alaska's F-35s 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/37897075

Nuclear Energy 2.0 is (Still) Upon Us 08/08/2025

Nuclear Energy 2.0 is (Still) Upon Us 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/37740365

Harnessing the Maelstrom 07/19/2025

Harnessing the Maelstrom 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. 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 “”. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/37466035

Big Dam, Little Dam 06/22/2025

Big Dam, Little Dam 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. But back then, we didn’t fully understand how dams could disrupt ecosystems; 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. But hydropower is a very site-specific technology—and there are plenty of ways to make it more environmentally friendly. 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/37106770

Concentrated Solar Power...Can Save the World? 06/13/2025

Concentrated Solar Power...Can Save the World? 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. 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/37003220

Balcony Solar 04/29/2025

Balcony Solar 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/36350390

The Heat Beneath Our Feet 01/18/2025

The Heat Beneath Our Feet You don’t need super high temperatures to harness geothermal energy. Under the right circumstances, a much smaller thermal gradient can be used as well. If we start digging, we’re guaranteed to find heat. It’s getting that heat to the surface where we can use it without spending more energy than we can actually get out of it -- that's the tricky part. We visit South Africa, Denmark, and upstate New York to learn about the not-so-hot geothermal resource that's beneath our feet all over the world. 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/34906090

Touching Magma 12/29/2024

Touching Magma 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/34641375

A Geothermal Primer 12/03/2024

A Geothermal Primer We cover the basics of geothermal energy before diving in to the more extreme versions of the technology in the next few episodes. And where better to kick off an episode on geothermal than with a mini-tour of Iceland — a country that has arguably made better use of geothermal than anywhere else on earth? In this episode, we’ll visit three sites in the southwest near the capital of Reykjavik before winding up in my own backyard in Alaska. 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. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/34641345

A Brighter History with Town Gas 07/31/2024

A Brighter History with Town Gas Before our towns and homes were lit by electricity, we relied on something called town gas for everything from reading lights to cooking. Eventually, town gas in most places was replaced by natural gas, which burned cleaner. But the switch from town gas to natural gas was not a one to one replacement, and it was not trivial. Because town gas, unlike natural gas, is mostly hydrogen. Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/32378407

Hydrogen: Too good to be true? 07/07/2024

Hydrogen: Too good to be true? Hydrogen is the most abundant element in the universe and is the energy source powering our sun. The idea of a hydrogen economy has been promoted for decades. So what’s holding us back? Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/32039662

Geology Plus: Carbon Capture and Enhanced Weathering 05/28/2024

Geology Plus: Carbon Capture and Enhanced Weathering We explore two carbon capture technologies that are exploiting natural geologic processes. But the companies working on these solutions are taking those natural processes and speeding them up a bit -- giving mother nature a little extra push in order to try and slow down climate change. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/31490327

Deep Under the Corn: Carbon Capture in North Dakota 05/20/2024

Deep Under the Corn: Carbon Capture in North Dakota Not every place has the right geologic settings for long-term carbon storage. But Alaska is one – in fact, Cook Inlet is the best tidewater location for storage on the entire west coast of North America. North Dakota is another. And for North Dakota this isn’t necessarily so much about mitigating climate change, it’s about building a new niche market to offer a service that others are willing to pay them for. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/31490272

A Small Town in Alaska Considers Going Nuclear 05/01/2024

A Small Town in Alaska Considers Going Nuclear Like much of rural Alaska, the town of Nome relies heavily on imported fuels for heating and power. The cost of heating oil here is well over $7/gallon. That’s what incentivizes a lot of Alaska communities to pursue new energy technologies, often well before they are part of the mainstream. Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/31079653

Nuclear Energy 2.0 is Upon Us 04/19/2024

Nuclear Energy 2.0 is Upon Us The U.S. Nuclear Regulatory Commission expects to receive 25 licensing applications in the next five years for a new generation of advanced reactors. But getting any of these designs from the drawing board to reality is going to require overcoming a lot of hurdles and uncertainties. Getting any new technology to market is challenging, but that challenge is even more acute for nuclear because of the complexities and costs that it entails. In this episode we’ll look at how two U.S. nuclear projects are navigating a complicated government licensing process to develop a first-of-its-kind technology that could make a pretty big difference in our ability to decarbonize our global energy supply. Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/30906203

Nuclear Energy: How Safe is Safe Enough? 04/02/2024

Nuclear Energy: How Safe is Safe Enough? Nuclear power is different from other energy sources. When we talk about new nuclear projects, it can still bring up strong and sometimes emotional reactions for people -- more so than with other sources of energy, and those opinions are much more divided across the political spectrum than any other technology. How did public perception change as nuclear moved from a technology of war to the energy solution of the future? And when it comes to energy technologies, or really any technology, how safe is safe enough? Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/30668288

Geothermal technology from Idaho to Iceland 02/27/2024

Geothermal technology from Idaho to Iceland Iceland is a powerhouse when it comes to harnessing the heat and the energy that’s pouring up through the tectonic crack that runs diagonally across the island. Icelanders originally got the idea for geothermal district heating from turn-of-the-century Idaho. But since then, the small nation managed to gather best practices from places like Boise, and then improve on them. And now they have the most concentrated know-how of geothermal energy in the world, and they market and export that expertise globally. Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/30197803

Iceland's recipe for cheap electricity 02/16/2024

Iceland's recipe for cheap electricity Iceland is widely regarded as a global leader in clean energy. Not only is their energy sustainable, it’s cheap, too. They have some of the most affordable heat and power in the world. But it was literally one of the poorest countries in Europe two generations ago. So, how did Iceland get here? What would they say are the most important choices and investments they made along the way? They share their secret recipe with us on this episode of Closing the Gap. Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/30022863

Bam! a Transition 02/16/2024

Bam! a Transition We can start exploring the current energy transition by first stepping back in time to look at the last big one – the one that gave millions of people around the world widespread access to electric power. Rural electrification remains an ongoing process today, particularly in rural and remote areas of the developing world. Getting electricity monumentally changed people’s lives. We'll go back to experience that transformation through the words and voices of those that were part of that struggle in rural Alaska. Closing the Gap is hosted by Gwen Holdmann and produced by Jennifer Pemberton. Music is from Blue Dot Sessions. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/30015863

Introducing Closing the Gap: Stories from the front lines of the global energy transition 02/14/2024

Introducing Closing the Gap: Stories from the front lines of the global energy transition I'm Gwen Holdmann, an energy researcher in Alaska. This podcast is where I share stories from the people I've met and the places I've visited around the world that are at the leading edge of the global energy transition: Geothermal beaches in Iceland, hydrogen-fueled tiki torches in Hawaii, solar-powered villages above the Arctic Circle, and power plants that are capturing their own greenhouse gas emissions and turning them into stone underground. /episode/index/show/3ea56fa7-834a-4cf3-9f0a-896b416c156e/id/29950828

Closing the Gap with Gwen Holdmann

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