We see black: dark concrete opens climate-positive doors

Anyone entering the new training and education center of the MARKGRAF construction company in Kemnath immediately notices that this concrete is different. The dark surface reveals what usually remains invisible—active climate protection. The color is created by green carbon, which is used as an additive in precast concrete elements. This carbon comes from SYNCRAFT reverse power plants and permanently binds CO₂ that was previously absorbed from the atmosphere by trees. The concrete cannot and does not want to hide its origin with color pigments – and that is precisely where its strength lies.

From the forest to the concrete.

Value creation begins regionally: in our reverse power plants, forest residues energy wood are converted into renewable energy and high-quality green carbon. This green carbon—also known as biochar—is particularly high-quality: EBC premium quality, a carbon content of over 90%, and high chemical stability. Compared to fossil coal, it is a true all-rounder – and what's more, it is obtained from renewable raw materials.

Together with the Berlin-based company ecoLocked , this green carbon is processed into ecoLocked Materials (eLM) – optimized for use in concrete and other building materials.

"The use of eLM in this innovative project marks a decisive milestone. It proves that sustainable construction with CO₂-negative aggregates is possible and offers enormous potential. The next steps are clear: in cooperation with other players in the construction, real estate, and concrete industries, we want to implement further projects in which CO₂ is stored on a large scale," says Hoang Anh Nguyen, Chief Growth Officer at ecoLocked.

_{Image rights: W. MARKGRAF GmbH & Co KG}

Facts and figures about the pilot project

The use of climate-positive concrete was implemented on an industrial scale for the first time at the MARKGRAF Training and Education Center. What exactly that means is explained below.

area of application

• Non-load-bearing prefabricated partition walls

• 2,500 m² gross floor area

Material

• 90 kg of ecoLocked materials per cubic meter of concrete

• 5,300 kg of Green Carbon

• Raw material basis: regional forest residues

climate impact

• 10.68 tons of CO₂ permanently bound

• Over 60% lower carbon footprint of prefabricated components

• Permanent carbon sink (1,000+ years)

Technical advantages

• Improved early strength

• Optimized workability

"For three years, we have been testing the use of new concretes, material compositions, and construction methods in several projects in order to offer our customers innovative and, at the same time, practical methods for reducing CO₂. (...) With this pilot project, we have demonstrated that biocarbon is not only a scalable technology for decarbonizing precast concrete elements, but also works under real-world conditions." Dr. Thorsten Opel, Innovation Manager at MARKGRAF

More than concrete: Green Carbon concrete into a CO2 sink

This project is more than just a pilot. It shows that the construction industry can not only reduce emissions, but also actively create CO₂ sinks.

Why the project is groundbreaking

• Industrial scale under real production conditions

• Technical performance at least on par with conventional concrete

• Visible sustainability

• Economically integrable into existing processes

• Closed regional cycle

Versatile applications of green carbon

Its use in concrete is just one of many examples. The possible applications are diverse. More detailed information on this can be found in the blog article "Green Carbon: The climate-positive all-rounder. " Briefly summarized in bullet points, the areas of application include:

• Construction industry & road construction
• automotive industry
• Steel industry & metallurgy
• Agriculture & farming
• Animal husbandry & feed
• Water & wastewater treatment

_{Image rights: W. MARKGRAF GmbH & Co KG}

Building innovations together

The project in Kemnath shows how climate-positive innovation comes about. And that great things can only be achieved by working together:

• SYNCRAFT supplies high-quality green carbon from reverse power plants

• ecoLocked develops CO₂-negative building materials from this

• MARKGRAF brings the technology into industrial practice

This interplay shows that climate protection is effective when innovation, technology, application, and the market work together.

Strong partnerships for climate-positive construction

In addition to ecoLocked, we are also working with other innovative companies to further develop climate-positive building material solutions. In the field of sustainable concrete and building material technologies ,CarStorCon® Technologies is one of our partners. Although CarStorCon is not part of this specific pilot project, we are united by the common goal of establishing green carbon as an industrially usable material—because with their Clim@Add® additive, concrete and asphalt applications become carbon sinks. This is well worth mentioning, because as in all matters relating to climate protection, "together" is the keyword that will take us forward.

"The high quality and consistency of green carbon from our reverse power plants enables us to create CO₂-binding building materials with climate-positive added value," Marcel Huber, CEO of SYNCRAFT.

Something to build on: concrete with a climate twist

The construction industry accounts for around 11% of global CO₂ emissions. Projects like this show that emission sources can be turned into permanent carbon sinks. The black concrete with the green influence symbolizes a new building culture—one that doesn't hide climate protection, but makes it visible. True to our motto, we are goingone step further together withecoLocked and MARKGRAF , proving that Reverse is forward.

Image rights: W. MARKGRAF GmbH & Co KG

Sources:

• ecoLocked project page MARKGRAF
  https://www.ecolocked.com/de-de/projects/markgraf-project

• ecoLocked / MARKGRAF Project Communication
  http://ambivation.com/de/2025/11/30/markgraf/

• SYNCRAFT References
  https://www.syncraft.at/blog/
  https://www.syncraft.at/references/