Experts on the way forward: New materials are the backbone of the green transition

Natural gas pipelines are made of steel, typically with a coating that ensures long life. Thus, it is a challenge to use them for transporting hydrogen, despite what many might imagine. Illustration: Force Technology

“There is a reason it’s called the Stone Age, the Bronze Age, and the Iron Age.”

This is what Mikkel Agerbæk, director of the Materials division at the Danish Technological Institute, claims.

“Every time humanity has taken a significant technological step forward, it happened through the use of new materials. And that’s how it’s going to happen this time as well,” the director says, referring to the green transition.

Therefore, Danish companies must think in terms of materials if they do not want to risk being overtaken by competitors, he points out.

“Right now, it’s crucial that companies stay up to date with developments. Framework conditions are changing rapidly these years, and new requirements are constantly being added. So there’s reason to look at one’s products and material choices and see if they can be made smarter,” Mikkel Agerbæk says.

According to him, it is important to be aware that we are in the middle of a transformation that requires new materials if we are to develop all the technologies that will bring us to the goal of the coveted 70 percent reduction in CO2 emissions by 2030. This applies, for example, to Power-to-X and the accompanying electrolysis and pyrolysis. It applies to the development of new electrodes, wind turbines, and ship engines. And it applies to the transportation of hydrogen.

Hydrogen in natural gas pipelines?

European transmission system operators (TSOs) dream of using the existing natural gas network to transport hydrogen around Europe, but gaseous hydrocarbons and pure hydrogen are substantially different.

Hydrogen is the world’s smallest molecule with an atomic mass of only 1.008 u, and it can leak out of even the smallest cracks. Just ask NASA, which is struggling with it in its space rockets. Hydrogen is flammable, and if it comes in contact with steel—which natural gas pipelines are made of (however, they are typically coated as well)—it creates hydrogen cracks.

“Using hydrogen in natural gas pipelines is not that simple. The idea is good, but we need to have a good grasp of what the network can handle and whether coating is sufficient. The transport of hydrogen also involves large temperature fluctuations and pressure differences, and all of this places great demands on the materials,” says Trine Nybo Lomholt, program manager of the materials and product testing department at Force Technology.

Force Technology is one of the Danish companies that focus on hydrogen, among other things. They work closely with other companies and universities, and the Danish company has just received EUDP funding to—together with the Danish Gas Technology Centre—become a Danish test centre for materials to handle hydrogen.

Force Technology is also working on the use of neutron radiation for the detection of hydrogen and analysis of materials, which is exactly what the neutron scattering facility ESS in Lund will be used for in a few years.

According to Trine Nybo Lomholt, compressors, pipelines, and tanks are some of the elements of the green transition that require a new approach in terms of the selection of materials:

“Our experience is that at the moment, people are hedging their bets when choosing materials—and risking that the green transition becomes much more expensive than necessary,” she says.

“For example, it’s not necessary to use high-strength steel to store a wide range of future fuels of the future. You can probably just use coating to solve the problems,” says Trine Nybo Lomholt, who feels that there are many new takes on surface treatments these years.

The problem of ammonia

The need for new materials is also pressing in several other areas. Developments in Power-to-X in particular interfere with the manufacture of electrodes, where the choice of materials is crucial for the production of, for example, hydrogen and methanol.

Several shipping companies have also begun to look at alternative fuels such as methanol and ammonia, which require new materials in the engines, such as replacing the copper alloys in the piston bearings.

“Copper and ammonia are a bad combination, so the engineers have to find new approaches—and if you change a part in an engine, then you typically also have to make new adjustments. So we will see a lot of these adjustments, which have to do with new material choices in particular,” Trine Nybo Lomholt says.

Keep an eye on 3D printing

At both Force Technology and the Danish Technological Institute, there is also another large area that concerns material researchers, namely the growing need for rare-earth elements and the desire for independence from monopolistic supply chains or individual countries such as China.

That agenda also plays into the desire to create a more circular economy, which both Mikkel Agerbæk and Trine Nybo Lomholt highlight as one of the most important focus areas for materials technology in the green transition—together with Power-to-X:

“We produce up to 20 million tons of polyurethane per year, which we can’t recycle. We can’t keep doing that. We have a huge task ahead of us in designing the right materials and products and ensuring that they can be recycled either mechanically or chemically. This will be the focus of researchers and companies for many years to come,” Mikkel Agerbæk says.

If you were to highlight one particular area that Danish companies should keep an eye on as a vehicle of development in these years—what would it be?

“3D printing. We have been talking about it for many years, but now we can work with so many materials in 3D printing that we can also print with metals. If I were a company, then I would look through my list of parts and see if any of them can be printed on the spot. It's making waves these years, and if you do a bit of poking around, you will stand stronger in the competition,” he says.