This idea is intended to make sustainable concrete suitable for mass production

In August of this year one summer day was hotter than the other. The reasons for this are obvious: too many CO₂ emissions have been emitted in recent decades. The construction and building sector is responsible for 38 percent of CO₂ emissions worldwide.

The cement industry alone accounts for eight percent of global and two percent of German greenhouse gases. The catastrophic consequences associated with global warming prompted the two founders, Leopold Spenner and Robert Meyer, to set up their start-up, Alcemy.

Their idea: a software that should simplify the production of sustainable cement and concrete. "The more sustainable the cements and concretes, the more difficult they are to produce," explains Spenner in an interview with "Gründerszene".

The reason: Concrete is ultimately a natural product consisting of sand and limestone. The quality of these raw materials varies - and this constantly influences the quality of the cement and concrete.

To counteract this and to keep production as simple as possible, factories mix in so-called cement clinker. This substance ensures that the building material becomes solid when water is added. The more cement clinker is used, the stronger the building material becomes.

The downside: Cement clinker is incredibly harmful to the climate. Or more precisely, its manufacture. Limestone and marl are ground, burned at more than 1400 degrees and melted. Millions of tons of CO₂ are released in Germany every year.

So if you do without cement clinker, or at least reduce the amount, you can save a lot of CO₂. However, he then has to establish more precise manufacturing processes in the factories – which in turn is expensive and time-consuming.

According to Spenner, more employees are then needed to carry out additional measurements and tests with the cement - and ultimately also to observe the production in minute detail.

"We try to automate the work steps, which are so time-consuming to do manually, by installing sensors and algorithms directly in the cement and concrete plants and in the concrete truck mixers," says Spenner, explaining his company's software program.

The sensors should always keep an eye on the quality of the building material. Cement manufacturers should be able to receive, monitor and control all the data via an app.

Spenner and Meyer founded Alcemy in 2018. Spenner spent much of his childhood working in his family's concrete and cement works. He later studied industrial engineering at the Karlsruhe Institute of Technology. His co-founder Meyer, who holds a doctorate in neuroinformatics, was previously an AI developer at Flixbus.

The first cement and concrete manufacturers are already using the start-up's software to reduce their share of clinker, including the Upper Bavarian Rohrdorfer Group and the Märker Group from Harburg.

The Berlin cement plant, which produces the building material for the Edge Tower in Berlin, was also very prominent. With a height of 140 meters, this will be one of the largest high-rise buildings in the capital and will be used to a large extent by Amazon. "The concrete that is used there has a very small proportion of clinker," says Spenner.

The prices that Alcemy charges for the software vary depending on the production volume. The cost of a conventional movement is around 50,000 euros. Since it was founded in 2018, VC firms have already invested four million euros in the start-up, including Local Globe and La Famiglia.

The company's goal is to sell its own software to even more cement and concrete manufacturers - also abroad. But the founders need staying power for this, says Spenner. “Change in the industry is extremely slow. It can take ten or twenty years for something new to catch on.”

"Everything on shares" is the daily stock exchange shot from the WELT business editorial team. Every morning from 7 a.m. with the financial journalists from WELT. For stock market experts and beginners. Subscribe to the podcast on Spotify, Apple Podcast, Amazon Music and Deezer. Or directly via RSS feed.