Sustainable construction with biochar: MARKGRAF and ecoLocked cooperate

Innovation rarely happens by accident – it needs space, focus, and above all people who actively drive it forward. One of these people is Dr. Thorsten Opel, Innovation Manager at MARKGRAF and the company’s interface with the startup world. His mission: identifying potential, spotting technologies, and bringing them into implementation together with internal and external partners. In an exclusive interview with Ambivation, Thorsten talks about MARKGRAF’s collaboration with the startup ecoLocked, the advantages of building with carbon concrete – and even about a palpable sense of new momentum in the construction industry.

Thorsten, you are Innovation Manager at the construction company MARKGRAF. The creation of such roles in companies is still a relatively new phenomenon. How did this come about for you?
Innovation is one of MARKGRAF’s central corporate goals. It became clear that day-to-day business often leaves too little time to drive innovative approaches forward. In addition, MARKGRAF is a large company with many departments where exciting ideas emerge but can easily fizzle out without central coordination. My task is to make these ideas visible and put them into practice.

Which tasks shape your everyday work? What role does working with startups play?
Technology scouting and monitoring market competitors are central topics. In addition, there are pilot projects such as the use of robotic systems (e.g., painting robots from Conbotics or HP SitePrint) as well as the cooperation with ecoLocked. I also travel a lot — to conferences and events — to stay at the cutting edge. Another important part of my work is positioning these topics internally: different stakeholders need to be involved, complex interrelationships communicated clearly, and new approaches presented convincingly. This is precisely where cooperation with startups proves valuable, as they provide fresh impulses and drive innovation in areas such as digitalisation and AI.

You were recently featured in the press due to your cooperation with the startup ecoLocked. How did you meet?
We had already identified biocarbon as a strategically important topic and wanted to move in that direction in a targeted way. The first personal exchange with ecoLocked took place at the Klimafestival für die Bauwende 2024 — and it quickly became clear that ecoLocked, with its expertise in concrete technology, is the ideal partner for MARKGRAF.

What convinced you about ecoLocked?
The decisive factor was ecoLocked’s technical expertise in concrete technology. This enabled us to keep the effort for the mix design low. Fundamentally, we are driven by CO₂ reduction — currently, there are hardly any scalable alternatives to decarbonising concrete, which is a major CO₂ driver.

What can you tell us about your current construction project, and how much ecological impact could you save compared to conventional materials?
With the Gerhard-Markgraf Education Centre, we are constructing an in-house training and education centre with three training halls for weather-independent training, an auditorium with stepped seating, and five modular training and meeting rooms. The partition walls of the training halls were modified with ecoLocked material. The CO₂ footprint of the concrete was reduced by approx. 80%, and that of the precast elements (including reinforcement) by approx. 60%. In total, more than 10,680 kg of CO₂ were permanently removed from the atmosphere — a strong signal for climate-friendly construction.

What challenges did you face in this project, and how did you overcome them together?
The biggest hurdle was the approval on a case-by-case basis. Thanks to our experience from the parallel construction of an office building at one of our production sites using carbon concrete precast elements, we had already internalised how to deal with regulatory and technical issues. This project was a milestone: a multi-storey new building, completely reinforced without metal using carbon concrete precast elements — not a single gram of structural steel in the load-bearing structure. Another challenge was integrating the new material into our production process, which required close coordination among all parties.

What distinguishes the biocarbon used from other innovative materials? You tested quite a lot. What’s your conclusion?
Biocarbon enables long-term binding of carbon from biomass residues in concrete. The material can also be integrated into existing processes in the future. Our conclusion: biocarbon is a promising approach that not only reduces CO₂ but also expands the value chain — towards a circular economy in which residual materials are used meaningfully. This allows us to contribute to climate-compatible construction that is technically feasible and economically viable.

The construction industry currently faces many challenges. Which developments still give you reason for optimism?
There is a noticeable sense of new beginnings. Many stakeholders are reflecting on the impact of their actions. Digitalisation, new materials, and circular economy are key drivers. Banks, too, are increasingly focusing on decarbonisation — a strong signal.

What recommendation would you give to companies that are just starting to think about becoming more innovative through cooperation with startups?
Be courageous in collaborating! Startups bring fresh perspectives and speed. Of course, there are prejudices, but reality is often different. Our example shows: the first contact was in November 2024 at the Klimafestival. Today — one year later — we are talking about a successful pilot project whose precast elements have been installed on the construction site since late summer 2025. Those who stay open can achieve real milestones.

Contact
Website: www.markgraf-bau.de

LinkedIn: Bauunternehmung MARKGRAF