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What’s behind the electrolyzer craze for green hydrogen?

Separating hydrogen and oxygen atoms grows as fuel for trucking and other industries

Cummins is among several companies pursuing electrolysis to make green hydrogen. (Photo: Cummins Inc.)

Making hydrogen today is a pretty dirty business. But that is changing as more companies seek ways to decarbonize the economy. 

One increasingly popular approach is applying renewable energy sources to centuries-old electrolysis to split molecules of hydrogen — the most abundant element in the universe — from its bonds with oxygen.

An electrolyzer separates water into oxygen and hydrogen, effectively the opposite of a fuel cell, which uses water and electricity to separate hydrogen and oxygen, creating water vapor as the only emission. In an electrolyzer, water is pushed through a stack with electricity. That pulls apart hydrogen and oxygen atoms. 

Producing emissions-free hydrogen is attracting federal and state incentives at unheard of levels. It bodes well for fuel cell electric vehicles. Especially long-haul trucks that could travel up to 1,000 miles on a single fill-up of liquid hydrogen. We’re not there yet, but the potential is greater than ever.

Companies embrace electrolysis

Companies are embracing the prospects. Cummins Inc.’s New Power division expects $3 billion in annual revenue from electrolyzers by 2030. Tier 1 automotive supplier Robert Bosch plans to invest up to $591 million in electrolyzer components by the end of the decade. German manufacturers ThyssenKrupp and Siemens Energy already make electrolyzers.

Fuel cell electric trucks expect to penetrate the U.S. market in small numbers by the second half of the decade. Even in the more mature seven leading European markets, they will not match the total cost of ownership of diesel trucks before 2030, according to research from the nonprofit International Council on Clean Transportation (ICCT).

But electrolyzers using renewable energy — solar and wind — along with generous incentives could match the cost of steam methane reforming (SMR), which accounts for more than 95% of the world’s hydrogen production. 

SMR costs about $1.50 to produce a kilogram of hydrogen. With a production tax credit and low-cost power, the price for electrolysis could drop from about $5 per kilogram. 

“We’re just at the cusp where we’re really going to see quite a bit of momentum, some of it being driven by the infrastructure bill, as well as the Inflation Reduction Act,” said Alex Savelli, Cummins managing director/Americas for hydrogen technologies. “But as the industry works to scale up, you’re going to see costs being at parity or more competitive than gray hydrogen.”

Centuries-old technology

Electrolysis was discovered in 1800, the same year Alessandro Volta invented the electric battery. Other chemists tried connecting their poles in a container of water. They found the current flowed through the water, separating hydrogen and oxygen at the electrodes, according to the Iberdrola Group, a global renewable energy developer.

A lot of electricity is needed for electrolysis, so it is expensive. Containing costs requires access to cheap electricity, such as a deal Nikola Corp. cut with Arizona Public Service to buy solar-generated electricity for 2 cents per kilowatt hour. The average price is twice that, Savelli said.

A complete electrolyzer system includes the stack, pumps, power electronics, a gas separator and other components such as storage tanks. 

Leveraging existing pipelines

Electrolysis probably won’t replace SMR, where high temperatures cause a reaction between natural gas and steam to produce carbon monoxide and hydrogen, so-called gray hydrogen. But electrolyzers making green hydrogen from renewable energy sources could run in the same pipelines — to a point.

“One of the things you can do is to leverage the natural gas pipeline infrastructure,” Savelli said. 

Blending up to 20% hydrogen is doable. More than that would require repurposing the pipeline because corrosion results from the presence of too much hydrogen.

“I think it’s necessary to have both technologies play out in the future and see what happens,” said Salim Youssefzadeh, CEO of WattEV, who researched hydrogen production before choosing to build high-power battery-electric infrastructure in California. 

“Maybe there’s different areas where hydrogen would be more economical, whether it’s on long-haul freight or some other area.

Cummins is all in

Cummins’ work in electrolyzers received an incidental lift with the $290 million purchase of Canada’s Hydrogenics in September 2019.

“The main target was access to fuel cell technology and the PEM [proton exchange membrane] technology that they had,” Savelli told FreightWaves. “They were also in the electrolyzer business. But the main point for us was the fuel cells.”

Hydrogenics helped Cummins launch fuel cell-powered passenger trains with Alstom in Germany. But the prospects of making green hydrogen fit the company’s Destination 2050 goal of carbon neutrality across all its products.

Hydrogen is used in refineries to remove sulfur from gasoline and in the chemical industry for producing fertilizers and ammonia. Volvo Construction Equipment employs hydrogen to make fossil-free steel for its trucks.

Three kinds of electrolyzers

Cummins manufactures three kinds of electrolyzers — Alkaline, PEM and the more nascent solid oxide electrolyzer. For trucking, PEM electrolyzers make the most sense, Savelli said.

“One of the greatest things we’ve been able to do with some of our engines is to increase power density because we went from mechanical fuel systems to electronic fuel systems,” he explained. “With PEM electrolysis, the power density you can get from a smaller footprint is almost analogous.”

As a hydrogen producer, Cummins could supply its hydrogen-fueled internal combustion engine planned for 2027. It already counts two large installations — an Air Liquide facility in Quebec, Canada, and a larger solar-powered PEM operation in Juno Beach, Florida, with Florida Power & Light. The plant consists of five electrolyzers capable of producing 10.8 tons of hydrogen per day.  

It is also adding electrolyzer production at an existing facility in Minnesota.

“We want to be both on the production side of hydrogen, as well as in helping people on the consumption,” Savelli said. “And the consumption would be either with fuel cells or it could be with a hydrogen ICE engine.”

Manufacturers differ in approaches to making hydrogen

Hydrogen production through electrolyzers and other methods has been part of startup electric truck maker Nikola’s business plan from the beginning. 

Volvo’s fuel cell joint venture with Daimler Truck, called cellcentric, leaves hydrogen production to others.

“We don’t need to step into that field ourselves,” said Lars Stenqvist, Volvo executive vice president of group trucks technology. “We don’t have that much of an opinion on electrolyzers for production of hydrogen.”

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Click for more FreightWaves articles by Alan Adler.

Alan Adler

Alan Adler is an award-winning journalist who worked for The Associated Press and the Detroit Free Press. He also spent two decades in domestic and international media relations and executive communications with General Motors.