On a bright September day on the harbor in Copenhagen, several hundred people gathered to welcome the official arrival of Laura Maersk.
Laura was not a visiting European dignitary like many of those in attendance. She was a hulking containership, towering a hundred feet above the crowd, and the most visible evidence to date of an effort by the global shipping industry to mitigate its role in the planet’s warming.
The ship, commissioned by the Danish shipping giant Maersk, was designed with a special engine that can burn two types of fuel — either the black, sticky oil that has powered ships for more than a century, or a greener type made from methanol. By switching to green methanol, this single ship will produce 100 fewer tons of greenhouse gas per day, an amount equivalent to the emissions of 8,000 cars.
The effect of global shipping on the climate is hard to overstate. Cargo shipping is responsible for nearly 3 percent of global greenhouse gas emissions — producing roughly as much carbon each year as the aviation industry does.
Figuring out how to limit those emissions has been tricky. Some ships are turning to an age-old strategy: harnessing the wind to move them. But ships still need a more constant source of energy that is powerful enough to propel them halfway around the world in a single go.
Unlike cars and trucks, ships can’t plug in frequently enough to be powered by batteries and the electrical grid: They need a clean fuel that is portable.
The Laura Maersk is the first of its kind to set sail with a green methanol engine and represents a significant step in the industry’s efforts to address its contribution to climate change. The vessel is also a vivid illustration of just how far the global shipping sector has to go. While roughly 125 methanol-burning ships are now on order at global shipyards from Maersk and other companies, that is just a tiny portion of the more than 50,000 cargo ships that ply the oceans today, which deliver 90 percent of the world’s traded goods.
The market for green methanol is also in its infancy, and there is no guarantee that the new fuel will be made in sufficient quantities — or at the right price — to power the vast fleet of cargo ships operating worldwide.
Shipping is surprisingly efficient: Transporting a good by container ship halfway around the world produces far less climate-warming gas than trucking it across the United States.
That’s true in part because of the scale of modern cargo vessels. The biggest container ships today are larger than aircraft carriers. Each one is able to carry more than 20,000 metal containers, which would stretch for 75 miles if placed in a row.
That incredible efficiency has lowered the cost of transport and enabled the modern consumer lifestyle, allowing retailers like Amazon, Walmart, Ikea and Home Depot to offer a vast suite of products at a fraction of their historical cost.
Yet that easy consumption has come at the price of a warmer and dirtier planet. In addition to affecting the atmosphere, ships burning fossil fuel also spew out pollutants that reduce the life expectancy of the large percentage of the world’s people who live near ports, said Teresa Bui, policy director for climate at Pacific Environment, an environmental organization.
That pollution was particularly bad during the Covid-19 pandemic, when supply chain bottlenecks caused ships to pile up outside of the Port of Los Angeles, producing pollution equivalent to nearly 100,000 big rigs per day, she said.
“They have been under regulated for decades,” Ms. Bui said of the shipping industry.
Some shipping companies have tried to cut emissions in recent years and comply with new global pollution standards by fueling their vessels with liquefied natural gas. Yet environmental groups, and some shipping executives, say that adopting another fossil fuel that contributes to climate change has been a move in the wrong direction.
Maersk and other shipping companies now see greener fuels such as methanol, ammonia and hydrogen as the most promising path for the industry. Maersk is trying to cut its carbon emissions to zero by 2040, and is pouring billion of dollars into cleaner fuels, along with other investors. But making the switch — even to methanol, the most commercially viable of those fuels today — is no easy feat.
Switching to methanol requires building new ships, or retrofitting old ones, with different engines and fuel storage systems. Global ports must install new infrastructure to fuel the vessels when they dock.
Perhaps most crucially, an entire industry still needs to spring up to produce green methanol, which is in demand from airlines and factory owners as well as from shipping carriers.
Methanol, which is used to make chemicals and plastics as well as fuel, is typically produced using coal, oil or natural gas. Green methanol can be made in far more environmentally friendly ways by using renewable energy and carbon captured from the atmosphere or siphoned from landfills, cow and pig manure, or other bio waste.
But the world today does not yet produce much green methanol. Maersk has committed to using only sustainably produced methanol, but if other shipping companies end up using methanol fuel made with coal or oil, that will be no better for the environment.
Ahmed El-Hoshy, the chief executive of OCI Global, which makes methane from natural gas and greener sources like landfill gas, said companies today were producing “infinitesimally small volumes” of green methanol using renewable energy.
“Companies haven’t done much in our industry yet quite frankly,” he said. “It’s all hype.”
Fuel producers still need to master the technology to build these projects, he said. And in order to finance them they need buyers who are willing to commit to long-term contracts for green fuel, which can be three to five times as expensive as conventional fuel.
Maersk has signed contracts with fuel providers including OCI and European Energy, which is building in Denmark what will be the world’s largest plant producing methanol with renewable electricity. The shipping company already has clients like Amazon and Volvo that are willing to pay more to have their goods transported with green fuels, in order to reduce their own carbon footprints.
But many other companies are not yet willing to pay the necessary cost for greener technologies, Mr. El-Hoshy said.
The missing piece, said Mr. El-Hoshy and others in the shipping and methanol industries, is regulation that would help level the playing field between companies trying to clean up their emissions and those still burning dirtier fuels.
The European Union is ushering in rules that encourage ships to decarbonize, including new subsidies for green fuels and penalties for fossil fuel use. The United States is also spurring new investments in green fuel production and more modern ports through generous domestic spending programs.
But proponents say the key to a green transition in the shipping sector are global rules that are pending through the International Maritime Organization, the United Nations body that regulates global shipping.
The organization has long received heavy criticism for its lagging efforts on climate. This summer, it adopted a more ambitious target: eliminating the global shipping industry’s greenhouse gas emissions “by or around” 2050.
To get there, nations have promised to agree on a legally binding way to regulate emissions by the end of 2025, which they would put into effect in 2027.
Yet countries have yet to agree on what kind of regulation to use. They are debating whether to adopt a new standard for cleaner fuels, new taxes per ton of greenhouse gas emitted or some kind of mix of tools.
Some developing countries, and nations that export low-value goods like farm products, say that strict regulation would raise shipping costs and be economically harmful.
Proponents of the regulation — including Maersk — say it’s necessary to avoid penalizing those who are trying to clean up the business, and provide certainty about the industry’s direction.
“There has to be an economic mechanism by which you level the playing field so that people are incentivized and not punished for using low-carbon fuels,” said John Butler, the chief executive of the World Shipping Council, which represents container carriers including Maersk.
“Then you can invest with some confidence,” he added.
Still, Maersk acknowledges that green methanol is unlikely to be the final solution. Experts say that the fuel’s reliance on finite sources of waste, like corn husks and cow manure, mean there will not be enough to power the entire global shipping fleet.
In an interview, Vincent Clerc, the chief executive of Maersk, said that the entire maritime sector was unlikely to ever be powered predominantly by methanol. But Maersk had no regrets about moving some of its fleet from fossil fuels to methanol now, then adopting new technologies as they become available, he said.
“This marks a real systemic change for this sector,” Mr. Clerc said, gesturing toward the vessel piled high with 20-foot containers in front of him.
Eric Leveridge, the climate campaign manager for Pacific Environment, said his group was glad that Maersk and other shipping companies were moving toward more sustainable fuels. But the organization is still concerned that “it is more for optics and that the impact is potentially being exaggerated,” he said.
“When it comes down to it, even if there is this investment, there’s still a lot of heavy fuel oil ships on the water,” he said.