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Podcast

How to Decarbonize the World’s Biggest Ships

Inside episode 24 of Shift Key.

A container ship.
Heatmap Illustration/Getty Images

Jesse is on vacation until August, so this is a special, Rob-only summer episode of Shift Key.

Shipping is the backbone of the modern economy. At least 80% of all goods worldwide are shipped as ocean cargo, and the global economy rises and falls on the free movement of gigantic ships across the sea. But container ships and bulk carriers burn what’s known as bunker fuel, one of the dirtiest fossil fuels. The international shipping industry generates 3% of global carbon emissions, a proportion that’s projected to rise through the century.

Most proposals to decarbonize ocean freight have focused on using ammonia or other zero-carbon liquid fuels. But Fleetzero, a Bill Gates-backed startup, is trying to use the only technology that it says can get cheap enough to compete with oil: batteries. The Alabama-based company is building batteries big enough to hybridize — and, eventually, power outright — the world’s largest ships.

This week, Rob chats with Steven Henderson, the cofounder and CEO of Fleetzero and a graduate of the U.S. Merchant Marine Academy. They talk about Steven’s history in the oil and gas industry, why batteries will beat liquid fuels, and how to put out a fire in the middle of the ocean.

This episode of Shift Key is hosted by Robinson Meyer, the founding executive editor of Heatmap.

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Here is an excerpt from our conversation:

Steven Henderson: What’s good about batteries, you can step into that, where you can use existing infrastructure and build on it. You don’t need a new fundamental technology to do this. The numbers to do this are not outside the realm of possibility.And if you think about it in terms of global … it’s about one-fifth of what you would need for electric cars and trucks.

So it’s not — yeah, these are big numbers. But if you think about an electric future, this is one of many parts, you know, so this is not going to be the hardest part on the grid. In fact, it’s a bunch easier because you don’t have to go send it across the country, and there are generating capabilities in and around ports, and you can use existing stuff.

Robinson Meyer: I would imagine even switching a ship from bunker fuel to electricity generated by natural gas, which is often just right there would be …

Henderson: Yeah, it’s a huge savings from carbon. And honestly, if you went to coal, it’s still cleaner. Ships, because of just the way they operate, there’s CO2 emissions, but it’s a huge SOx and NOx, it’s a sulfur and nitrous oxides emission. And at least with a stationary coal powered plant, at least in the West, there’s regulations on what you can send out the stack. When you’re in the middle of the ocean, these things, you know, sometimes they’re choking up some pretty nasty stuff.

So it’s an advantage, even if you go from coal. Obviously, we hope that all electricity coming into this is going to be clean over time. But if you suddenly have, oh, I need 100 megawatts of power, and I need to, you know, swap out this power plant — well, what if I need 300 megawatts of power? Now I’m going to build a new power plant, and the economics on that are going to stand on their own, and I can build it clean from the beginning, so I don’t have to scrap the existing infrastructure to make the grid clean.

So that’s why it’s super important to electrify the consumers, and that increased demand on the grid is how you clean up the grid.

This episode of Shift Key is sponsored by …

Watershed’s climate data engine helps companies measure and reduce their emissions, turning the data they already have into an audit-ready carbon footprint backed by the latest climate science. Get the sustainability data you need in weeks, not months. Learn more at watershed.com.

As a global leader in PV and ESS solutions, Sungrow invests heavily in research and development, constantly pushing the boundaries of solar and battery inverter technology. Discover why Sungrow is the essential component of the clean energy transition by visiting sungrowpower.com.

Music for Shift Key is by Adam Kromelow.

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