Submitted
2025 Global Climate Challenge

Cyanoskin

Team Leader
Antoinette Nothomb
We are developing the first living algae-based coating that captures carbon directly from the air when applied to building facades. As the algae grow, they absorb CO₂ through photosynthesis, turning the surface of buildings into active carbon sinks. Algae hold incredible CO₂ capture capabilities. Comparably, 30 grams of algae absorb the same amount as a fully grown tree annually.
What is the name of your organization?
Cyanoskin
What is the name of your solution?
Cyanoskin
Provide a one-line summary or tagline for your solution.
Asset light Carbon capture technology through an algae based-coating
In what city, town, or region is your solution team headquartered?
Londres, Royaume-Uni
In what country is your solution team headquartered?
GBR
What type of organization is your solution team?
For-profit, including B-Corp or similar models
Film your elevator pitch.
What specific problem are you solving?
The construction industry is responsible for nearly 40% of global CO₂ emissions, making it one of the most polluting sectors worldwide. In dense urban areas like London, construction sites significantly contribute to localised air pollution, CO₂ output, urban heat, and surface water runoff. Globally, the building sector consumes 36% of energy and emits 39% of energy-related carbon, affecting billions through climate change and poor air quality. In the UK, over 3 million people live in areas exceeding legal air pollution limits, with construction identified as a key contributor. This places pressure on asset owners and contractors to submit to regulatory demands to emit less during construction periods. However, the lack of scalable, low-cost, low-risk carbon capture solutions has left developers with limited options to meet sustainability goals. Current alternatives, such as heat pumps, sustainable cement, or carbon credits, demand high expenses or hold low trust, which the industry cannot afford to take. However, with current regulations in place, all actors are obliged to move in that direction.
What is your solution?
We are developing the first living algae-based coating that captures carbon directly from the air when applied to building facades. As the algae grow, they absorb CO₂ through photosynthesis, turning the surface of buildings into active carbon sinks. Algae hold incredible CO₂ capture capabilities. Comparably, 30 grams of algae absorb the same amount as a fully grown tree annually.
Who does your solution serve, and in what ways will the solution impact their lives?
Our solution is designed to serve asset owners (e.g. Iron Mountain, CMA CGM, Diageo), construction firms (Morgan Sindall, Landsec), and developers (MACE). Currently underserved by existing carbon reduction tools, which are often costly, high-maintenance, or unscalable. Cyanoskin aims to develop a coating removing up to 66.6 kg of CO₂e per litre per m² per year. For larger applications, such as coating a 1,000 m² warehouse façade, we can capture up to 66.6 tonnes of CO₂ annually. Cyanoskin creates zero-maintenance, biophilic spaces that support health and recovery. For councils and industrial sites, it’s a cost-effective way to meet net-zero goals without using extra land, power, or water.
Solution Team:
Antoinette Nothomb
Antoinette Nothomb
COO