How common chemicals could help clean up global shipping

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I’ve been thinking a lot about boats lately, and not just because it’s been hot in New York for days and hopping into any body of water sounds incredibly refreshing right now. 

I’ve actually got boats on the mind because there was just big news in global shipping from the International Maritime Organization, the UN agency in charge of regulating the vessels that carry everything from tennis skirts to EV batteries around the world. On July 7, the IMO agreed to new climate goals, setting a target date of “by or around 2050” to clean up the industry’s act and reach net-zero emissions. 

This is a big deal for the shipping industry, which didn’t have any broadly accepted target before. But as we all know, a goal is more of a starting point than an end. So let’s take a look at the technology that companies might turn to as they chase net-zero shipping. 

Starting small

Aside from the net-zero target, a crucial piece of the IMO agreement is a set of checkpoints along the way to 2050. These aren’t binding, but the IMO did set a target to cut emissions 20% by 2030, and 70% by 2040. 

Those checkpoints could be critical in spurring industry to take action, said Madeline Rose, who was present for the IMO proceedings and is a senior director of climate at Pacific Environment, an environmental group. 

I was especially intrigued by that first checkpoint, because 2030 is coming up fast. (Fun fact: The first day of 2030 is actually closer to today than the last day of 2016 is.) And a 20% emissions cut for an industry that’s often called hard to decarbonize sounds like a lot. But digging into it, I was surprised to learn that there are actually several fairly straightforward avenues the industry could take to reach this target, and likely with time to spare. 

In fact, just slowing down ships could be enough to achieve that 20% cut in greenhouse-gas emissions. Faster ships require more fuel than slower ships, even when traveling the same distance. And other technology options are on the table too, like new fuels and devices like sails or special rotors that can harness the wind to boost ships. That trifecta could actually add up to a nearly 50% decrease in emissions by the end of the decade, according to one study from environmental consultancy CE Delft. 

I wrote all about these near-term measures that shipping could take, so check out my story for more on that. In the meantime, let’s set our sights further toward the horizon and consider what shipping might look like in 2050. 


Slowing ships down, adding wind assistance, or even adding coatings to make boats more slippery in the water will all cut down on the amount of fuel used. But that isn’t how we’re going to reduce greenhouse-gas emissions to zero. That’s because even as you get more efficient, you’ll still be using fossil fuels that produce the climate-warming emissions.

So in the longer term, shipping will have to find more fundamental ways to clean up its act, like finding new power sources. 

Batteries will find their way into some ships, but they’ll probably be limited to shorter voyages, because most batteries today would be too bulky and heavy to carry enough energy for the longest trips.

One study, published last year in Nature Energy, estimated that journeys of up to 1,000 kilometers (620 miles) could be economically serviced by battery-powered ships today. If batteries continue to get cheaper and pack more energy into a smaller package, that could soon stretch to 3,000 kilometers (1,860 miles) (or even longer, if environmental costs are taken into account and ships can be designed to carry more weight). 

But for the longest routes, we’ll likely still need to rely on fuels. 

One option is ammonia, which I’ve written about before. This chemical, today used as a fertilizer ingredient, could power ships in two different ways. It could be used in combustion engines, since as a non-carbon-based fuel it doesn’t produce carbon dioxide when burned. Ammonia can also be used as a way to store and transport hydrogen, which could then be used in fuel cells to power electric ships. Check out my story from last year for all the details. 

Other companies are looking to methanol as a potential green fuel. There’s still carbon in it, so it does produce carbon emissions when burned, but the fuel can be produced using renewable electricity and carbon dioxide pulled from the atmosphere or from biological sources, so the balance of emissions could be low, or even zero. 

Shipping giant Maersk recently announced that it gathered enough bio-methanol for a maiden voyage from South Korea to Denmark. Availability of bio-methanol and other low-emissions fuels is still a bottleneck in the industry, but the company has ordered over a dozen methanol-powered ships. 

I’ll be following work on these alternative power sources, so stay tuned for more from me. And for the record, we’re closer to 2050 than we are to 1996. 

Related reading

Check out my story about how the shipping industry can start making emissions cuts right now. 

Ammonia is a popular candidate for global shipping, but the fuel has some potential roadblocks to overcome first. I wrote last year about these two sides of the ammonia coin. 

Ships might not be the only thing powered by methanol: in China, some companies want to use it to power vehicles. My colleague Zeyi Yang reported on that trend in the fall

Another thing

Syracuse, New York, could soon go through a time of immense change. The city is marked by poverty—and it will soon be home to four massive chip factories, which will cost a total $100 billion to build. My colleague David Rotman took a deep dive into what this could mean for the area, and what an influx of funding from the US federal government will mean for other cities across the country. Give it a read here.

Keeping up with climate

Over 60,000 people died because of Europe’s summer heat waves last year. Italy, Spain, and Portugal saw the highest mortality rates. (New York Times)

→ I wrote last year about how changing summer heat patterns will likely bring more air conditioning to the continent, and why that might be a problem. (MIT Technology Review

A decades-old coal-fired power plant in North Dakota is getting retrofitted with a carbon capture system. The project will cost over $1 billion, and it could be a major test for the technology. (Inside Climate News

Toyota announced ambitions to get solid-state batteries into cars in 2027. But this is far from the first time the automaker has made promises about the technology. (Financial Times

→ If they make it into EVs, solid-state batteries could speed charging times and boost vehicle range. (MIT Technology Review)

A test of an enhanced geothermal system in Utah hit a big milestone, connecting deep tunnels drilled underground. Enhanced geothermal projects could help bring renewable energy to places where traditional geothermal isn’t accessible. (Deseret)

There’s a pot of money at the Department of Energy with hundreds of millions of dollars in it, and the office wants to use some of it for public transit. (Bloomberg)

The Biden administration just approved a massive offshore wind farm. It’s off the coast of New Jersey and could power as many as 380,000 homes. (Grist)


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