It is an appointment that visibly brings joy to the political leaders present. The Minister of Economy, Robert Habeck (Greens), and the Prime Minister, Daniel Günther (CDU) participate in the first symbolic inauguration ceremony of a climate-neutral cement plant in Lägerdorf (Schleswig-Holstein). The Holcim plant is expected to produce no more emissions by 2029, the first plant of its kind in Germany.

In principle, cement production has not changed for centuries: limestone powder is heated in a kiln together with clay, sand and iron ore to a temperature of 1,450 degrees Celsius, and then the resulting so-called clinker is ground with plaster to form cement. However, this process releases huge amounts of CO2, which is also a problem because humanity uses an extremely large amount of cement. Cement production accounts for between seven and eight percent of global CO2 emissions.

In and out

In Lägerdorf, new oven technology from Thyssenkrupp subsidiary Polysius aims to make the manufacturing process much cleaner. In the process called “pure oxyfuel”, normal ambient air is not added to the combustion, but chemically pure oxygen is added. The CO2 produced during combustion is also pure, at least in the chemical sense.

The big advantage: chemically pure CO2 can be separated relatively easily. Instead of escaping uncontrollably into the atmosphere, CO2 can be stored underground (the so-called “carbon storage” process) or reused for other industrial processes, such as the production of carbonated water in the food industry. This is expected to save 1.2 million tonnes of CO2 each year.

Habeck's little coup

The Minister of Economy also used his speech as a small blow or as motivation, depending on your point of view. On the west coast of Schleswig-Holstein, the region of greatest expansion of wind energy, you can see that green electricity is becoming a geographical advantage, says Habeck, also from Schleswig-Holstein. The “oxyfuel” process requires large amounts of electricity, which should ideally be environmentally friendly; Only then is the process climate neutral. “And this is a message we can hear in Germany, where people are hesitant to move forward with the expansion of renewable energy.”

Compared to southern Germany, Schleswig-Holstein has two advantages for the green industry of the future: on the one hand, the availability of abundant green electricity. And, on the other hand, the proximity to the North Sea, where a large part of the captured CO2 will be stored underground.

Open questions

“Of course we will not be able to do without CO2 in the future,” stressed Schleswig-Holstein Prime Minister Günther. Likewise, not all CO2 emissions can be prevented. Therefore, in addition to storing carbon dioxide, he also advocated continuing to use greenhouse gas. In order to continue using CO2, which will also be captured at the Holcim plant, a reasonable infrastructure is needed and there are still some tasks ahead for the state and federal government.

In fact, some questions remain unanswered. Expensive pipelines would have to be built to transport the CO2. It is also unclear how competitive green cement will be in terms of price. According to Holcim, the new process will be ten to twenty percent more expensive than the old one.

“We see that a lot is being done”

But what happens after the opening ceremony? “We have basically completed the planning and now we will start mainly with the administration building,” explained Holcim CEO Thorsten Hahn. Then the renovation itself should begin. Eventually around twenty new buildings will be built on the factory site. The new furnace will also be built next to the old furnace. Once completed, the old one will be dismantled, Hahn says.

In January 2023, the EU pledged funding of 109 million for the conversion to a climate-neutral production facility. The company itself claims that it is investing an amount of three-figure millions.

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“At Holcim we see that a lot is being done for nature conservation,” said Alexander Schwarzenlose of the Schleswig-Holstein Nature Conservation Association. However, he would like to see a clear commitment to renaturalization. The renaturalization of soil used for chalk extraction in particular leads to increased biodiversity.

The German Federation for the Environment and Nature Conservation also criticized: According to the BUND, the cement plant needs three and a half times more energy and fifteen times more cooling water after renovation. The planned extraction of chalk, with which Holcim wants to secure its supply of raw materials for the next 100 years, is also destroying forests and grasslands on former wastelands. Therefore, the BUND calls for effective climate compensatory measures.