As the shipping industry looks to reduce emissions, methanol is gaining a foothold as an alternative fuel source.
Maersk has ordered 19 container vessels fitted to burn methanol. Mediterranean Shipping Company (MSC), which last year surpassed Maersk as the world’s largest shipping company, joined the Methanol Institute, the trade association for the methanol industry, signaling an interest in the fuel source. The third-largest global shipper, France’s CMA CGM, ordered six methanol-ready ships. Also, a Bill Gates-founded energy investment firm is backing a Danish manufacturer’s production of methanol-powered fuel cells for ships.
Four parts hydrogen, one part oxygen and one part carbon, methanol is an organic chemical compound. When distilled for fuel, it is a colorless liquid that smells like ethyl alcohol.
Burning methanol emits fewer pollutants than burning gasoline or diesel oil. But it has not been widely deployed as a greener fuel in part because methanol is not necessarily net gain for environmental impact. Methanol is traditionally made from natural gas or coal using processes that release enough greenhouse gases to negate any benefit from switching to methanol as a fuel source.
Methanol can be made from carbon dioxide capture or from biomass, such as agricultural waste or sewage, thus creating a “green” methanol. If made in such a way, methanol is a net win when compared to heavy fuel oil, diesel or any other common marine vessel fuel source. A 2020 working paper from the International Council on Clean Transportation found that methanol from plant biomass cuts fuel emissions by 70 to 80 percent when compared to standard marine gas oil.
For the shipping industry — which is responsible for 3 percent of the world’s gas emissions — one of the primary benefits of methanol is that fossil fuel-burning ships can easily be adapted to use it as a fuel.
“In general, it can come pretty close to a drop-in type for existing engines, with some upgrades to the engines, in terms of making sure that the fuel systems can handle it correctly,” Edward Carr, vice president of operations for Energy & Environmental Research Associates, told Professional Mariner.
This is particularly important for an industry that uses vessels for decades, factoring that long lifespan when ordering new ones. Also, methanol can be stored and transported in the same way as natural gas, so it can utilize existing infrastructure.
“Methanol can be bunkered in things that are very, very similar, if not the same, as current bunker infrastructure,” Carr said. “You may need to change the linings on the tanks and pipelines and the seals on pumps and things like that. But methanol is stable in atmospheric conditions. The question is whether it is economical to replace your bunker fuel with methanol.”
There are a few downsides to methanol for the shipping industry. One is that methanol is less energy dense than other marine fuels. Carr’s firm concluded that conventional marine fuels are 2.15 times more dense. One would need more than twice as much methanol to go the same distance.
This issue is compounded by another major issue: insufficient production of green methanol. Currently, there are only 18 methanol production plants in the U.S. Most are clustered along the Gulf Coast and most production relies on natural gas.
Green methanol is not available at enough ports to create the kind of dependability that shipping companies consider a must, according to Carr.
This is a chicken-and-egg situation: Without an increase of production, shipping companies won’t have adequate sources of green methanol to justify investment in converting ships. Without shippers demanding it, producers don’t have incentive to make more. This is one reason Maersk arranged partnerships with nine energy companies as it awaits its methanol-burning fleet.
Another downside is safety hazards: Methanol flames are almost invisible in bright sunlight and do not trigger smoke detection systems. Ships would need to install infrared detection to safely use methanol.
As global shipping companies figure out how to implement more methanol usage, some naval architects are using methanol-burning vessels to meet local emissions goals.
Elliot Bay Design Group is at work on a methanol power and charging barge, an idea was partially spurred by California regulations requiring vessels to use only shore power or strict low-emissions fuel sources when berthing, Mike Complita, vice president of strategic expansion, told Professional Mariner.
Having ships pile into the dock to plug into shore power is expensive and logistically cumbersome. Battery barges that can go out to charge ships’ electrical systems while they are anchored are limited because of the lengthy time they need to charge themselves. A charging vessel that runs on low-emissions methanol might be a solution, said Complita.
“With this system, we fuel up, we take it out, [and] the ships can come and go; they can rotate,” he said, “and we can keep the vessel working constantly without needing to return to the dock frequently. So, it’s a lot cheaper than a shore-based application or an all-battery application and provides equal or close to equal the environmental benefits.”
The barge will be equipped with methanol reformers that convert methanol into hydrogen, which will then run through fuel cells to create electricity. Complita is also overseeing EBDG’s methanol-powered towboat project currently underway for Maritime Partners. That vessel is slated to be finished later this year.
“I believe methanol will be the choice of the future for a number of reasons,” he said. “Largely, due to its safety and relative ease of handling and relative ease of production. That gives it a leg up over most of the other competing alternative fuels.”