Hitting the gas for hydrogen

In some places the future is already here. Take the northern coast of Germany, for example, where the land is flat and the horizon wide. Meadows alternate with fields, and wind turbines and solar modules generate renewable energy. Over the last two years, this region has seen the addition of five white containers that hold electrolyzers from H-Tec Systems. These use locally generated electricity to split water into hydrogen and oxygen. The hydrogen goes on to further use.

While it may sound simple, there is a whole lot more behind it, because here is a piece of the global energy revolution puzzle. Hydrogen produced with wind, water and solar energy is CO2-free – also known as ‘green’. “Green hydrogen could be one of the keys to the energy transition and help industry achieve a breakthrough in decarbonization,” says Uwe Wagner, Global Industry Manager for Power & Energy at Endress+Hauser.

This emissions-free gas has numerous uses in many sectors. It makes excess production of green energy storable. It can be fed into the gas grid. And it can be converted to electricity and heat in fuel cells. In the chemical industry, it serves as a feedstock for producing ammonia and methanol. In the oil industry it’s used in the refining process. Combined with CO2, it makes synthetic methane and synthetic fuels. “And in the steel industry, green hydrogen can replace coal as a reducing agent in blast furnaces that manufacture pig iron,” says Jens Hundrieser, European Industry Manager for Energy at Endress+Hauser.

To date the global demand for hydrogen, currently at 90 million tonnes annually, has been met almost entirely with inexpensive gray hydrogen produced by steam reforming of fossil fuels. Electrolysis currently generates just 0.03 percent. Still, more than 30 countries have adopted or are planning a national H2 strategy. In the EU alone, the goal is to increase production of renewable hydrogen to 10 million tonnes per year over the period 2024 to 2030. Alliances are driving the project forward.

There are plenty of challenges in hydrogen production. “Electrolysis relies on lots of auxiliary systems coupled together and decked out with measuring points for all kinds of parameters that require continuous monitoring. Hence the need for a considerable amount of reliable and precise measurement instrumentation,” explains Andreas Brinner. Then there is the fact that H₂ is the lightest of all gases, with extremely small molecules. “Hydrogen easily diffuses through lots of materials and can cause metals to become brittle,” says Prasanth Sreekumar, Global Industry Development Manager for Gas at Endress+Hauser. “This calls for careful selection of materials, instruments and seals.”

Like many other electrolysis specialists, both H-Tec Systems and ZSW put trust in instrumentation from Endress+Hauser. “We have long relied on measurement technology from Endress+Hauser and value its quality, reliability, precision, media resistance and versatility. The large portfolio gives us many options,” says Andreas Brinner. Other pluses include the instruments’ compliance with functional safety (SIL) and explosion protection requirements. This in turn guarantees a high degree of plant safety. “We can cover a wide range of measurement tasks in our process with the sensors from Endress+Hauser,” confirms Martin Linder, Development Engineer at H-Tec Systems. “What’s also important for us is their straightforward installation and commissioning.”

Both ZSW and H-Tec Systems are currently focused on reducing the cost for green hydrogen in order to make it more competitive. To do that, data is being used to optimize the electrolysis process and increase the power rating of the individual modules comprising the systems. “At the moment we’re making inroads into increasingly larger areas,” reports Emily Pröll. “That means more and more systems in the double-digit megawatt range.”

Another goal is to enable the series production of electrolyzers. This is where H-Tec is working with industry and research partners, within the framework of the German government-funded flagship project H₂Giga, to develop new production processes for PEM electrolysis stacks and electrolyzers. ZSW is also addressing the question of how electrolyzer technologies can be scaled further. “We’re conducting research into materials and manufacturing technologies that will allow implementation on an industrial scale,” says Andreas Brinner. The scientists are also developing a concept for large-scale manufacturing of electrolyzer blocks.

The market is already demonstrating how progress is being made with green hydrogen. Shell has been operating Europe’s largest PEM electrolyzer featuring 10 megawatts of capacity since 2021. And in 2022, industrial gas manufacturer Linde will bring online the world’s largest PEM electrolyzer, rated at 24 megawatts. Several 100-megawatt projects across the globe are also planned. The focus is primarily on regions that have an abundance
of renewable resources for electrolysis: inexpensive energy from solar, wind or hydropower plants, as well as seawater that can be desalinated.

It seems the future is picking up even more steam. Whether the impetus is sufficient depends on more than just investments, new technologies and industry’s willingness to change. “The political frameworks must be right as well,” emphasizes Jens Hundrieser, who recently started representing Endress+Hauser in the European Clean Hydrogen Alliance. Above all, that means one thing: “A global carbon pricing mechanism has to be established. Only then will the energy transition be successful. Only then will the hydrogen economy prevail. And only then can the global climate goals be achieved.”