Greening the Shipping Industry

Jan 13, 2024

Photo: Shutterstock

The Fletcher School's Rockford Weitz discusses a trailblazing proposal for creating the system needed to decarbonize this very complex industry

In the global race to reduce carbon emissions, some big—very big—players are leading the pack: ships.

Picture massive freighters and container ships—vessels whose engines alone are the size of whole buildings. Maritime shipping, the industry that powers those ships, produces 5 to 7 percent of the world's carbon emissions. Reducing the industry's impact would make an enormous difference in efforts to shrink the global carbon footprint.

Fortunately, shipping industry leaders have shown a keen interest in decarbonizing through collaborations with other stakeholders—governments, the United Nations, the oil and refining industries, ship-building and marine engine-making companies, to name a few. At a 2019 meeting of the International Maritime Organization, the London-based UN body that governs international shipping, key stakeholders committed to cutting emissions in half by 2050 (compared with 2008 levels).

However, the complexity of the industry, its international nature, and the technological and logistical obstacles to reducing reliance on fossil fuels present significant challenges.

"We’re trying to change a system that grew organically over 100 years across 190 jurisdictions around the world," explained Rockford Weitz, professor of practice in maritime studies and director of the Maritime Studies Program at the Fletcher School of Law and Diplomacy. "You don't create overnight green fuel options that can be sourced globally to serve a widely dispersed industry that needs accessible refueling stations—you have to take a systems approach."

To develop that approach, Weitz and a multidisciplinary team of researchers at Tufts are exploring new ways to power ships.

Partnering with the School of Engineering's Eric Hines, professor of practice in civil and environmental engineering, and Andrew Ramsburg, associate professor of civil and environmental engineering, and with Luke Davis, assistant professor of chemistry in the School of Arts and Sciences, Weitz and team have brought to bear on the challenge their expertise, in fields ranging from maritime law and arctic studies, to entrepreneurship and social innovation, to electrolysis and offshore wind energy.

On June 15, Weitz, along with Hines and a host of other experts in research and innovation shaping the future of our oceans, will speak at Tufts’ Bluetech Innovation Day. In addition to expert panels, the event will feature conversations with investors, showcases from companies in the industry, and opportunities to learn about the blue economy in Massachusetts and beyond.

Weitz sat down with Tufts Now to discuss his team's groundbreaking research, which he’ll be presenting at the conference.

The great thing is, the technology already exists; it just hasn't been applied yet in the shipping, gas and oil, or refining industries. The real innovation barrier is one of creating a value chain, or supply chain, that is nonfossil-fuel based. We need to develop a green-fuel value chain that serves shipping companies.

As far as how we create the fuel goes, that comes down to simple chemistry (simple for my colleague Luke Davis, at any rate!). Essentially, you take water—either fresh or salt water—and you use electrolysis to break it down into its component parts. The oxygen goes out into the atmosphere and is good for us living things. To the remaining hydrogen, you add nitrogen, which is conveniently the most abundant element in the air. The result is ammonia, and if you carry out the process with electricity produced using clean energy, then it's green ammonia.

That green ammonia can be used to fuel ships. You can also use methanol, which is similar but a more complex hydrogen-based green fuel. Some shipping lines prefer it to ammonia because it is easier to store and handle. But still, either fuel can be used and both can be produced with existing technologies.

For a century, the shipping industry—based on fossil-fuel ships—has had a partnership with the oil and gas business and the refining business; together, these industries have built the infrastructure for refueling ships in any number of places.

For example, you pump oil out of Saudi Arabia and send it to Singapore. There, it gets refined and the portion of the oil that ships use, bunker fuel—which is very dirty—gets stored. It's convenient to store it there because it's on one of the world's busiest shipping lanes, the Malacca Straits. Ships regularly go through there, so they can refuel easily.

Our idea is to create a new system for green energy that allows all the parts of the complicated supply chain to remain connected. You have to get buy-in from the shipbuilders and engine manufacturers, who are mostly in Korea, Japan, China, for creating the right kinds of engines and vessels. You have to find places to create green ammonia and methanol and space for it to be stored. And you have to make use of shipping lines that will allow a large number of ships using green energy sources to stop and fuel up.

Absolutely. First of all, the Danish shipping company Maersk, the world's largest operator in containerized shipping, raised its hand at the 2019 International Maritime Organization's meeting and said, "We’ll lead the way in decarbonizing by 2050." That gave all the stakeholders the impetus to move forward with a plan.

Maersk is putting billions of dollars into the effort, building eight new container ships that will be ammonia-fueled. To put that in perspective, each ship costs $200 million dollars—that's a $1.6 billion-dollar investment by a private company. Previously, energy producers might have been reluctant to create green ammonia, because they didn't have anyone to sell it to. Maersk is solving that problem, and with encouragement at the UN level and from so many governments—the Danish government, the European Union governments—the way is paved.

Also, Saudi Arabia has stepped up. The biggest oil exporter in the world—they’re going to build the world's largest solar-farm-to-green-hydrogen-system in their desert, and they could ship ammonia to global markets. (If there's one thing Saudi Arabia has in addition to oil, it's sun.) So already you have big industry and major economies investing in this, and it's becoming a multibillion-dollar endeavor.

This is the part I get really excited about. The team I’m working with has come up with a plan to harness wind power in a way that will make it easy to create and store green ammonia, and that will allow ships to refuel along a major route.

Essentially, there are two ways to create green ammonia without using fossil fuels to power the electricity you need for the process: with solar power and with wind power. The latter is a specialty of Tufts—we have a lot of expertise in that area.

My team is saying that you could scale-up offshore wind production in a place that's not near a population center. In the Aleutian Islands off the coast of Alaska, the wind blows 365 days a year, 24/7. It's as good as it gets anywhere on the planet.

So let's build a huge windfarm there. Put in 1,000 turbines—you have to think big. Connect the turbines to an undersea grid that comes up to a floating electrolyzer. You have an almost unending supply of water there in the north Pacific. Get the hydrogen from the water in an electrolysis process, convert it to ammonia, and store it right there, because—and this is the beauty of the whole thing—the Aleutian Islands lie right along a major shipping route. The shortest distance from, say, Seattle or L.A. to cities in Japan and China is north—not directly west. Just like airplanes that fly that route past Alaska when traveling from the U.S.'s West Coast to Asia, ships sail along that route. Well, guess what? They could refuel there.

That's why this idea is so intriguing. Already, ammonia is shipped globally with chemical tankers. In the scenario I described, you’d have so much ammonia, it would exceed the needs of the shipping industry. So in addition to creating it in the Aleutian Islands and giving ships the opportunity to refuel cleanly up there, you also could ship it from there in exactly the way we ship oil and gas now. A ton of different industries could start making an easier transition to green fuel that would be readily available. Also, we’d be creating a lot of jobs in Alaska!

What I really love about this is that it's an interdisciplinary, international, cross-industry endeavor—and it's realistic. It tackles a global-scale problem in a meaningful way. And it's a concrete way for Tufts to contribute to the world's transition to clean energy.