The Danish construction sector accounts for approximately 10% of national CO2 emissions, while increasingly stringent building regulations place greater emphasis on reducing embodied carbon. Conventional lightweight aggregate clinker blocks (LWCB) rely on lightweight aggregates, making it difficult to achieve significant reductions in their climate impact. CHARBLOCK aims to develop, document and demonstrate a carbon-negative LWCB by replacing lightweight aggregates with biochar. The project will identify the optimal biochar replacement rate and validate architectural applications.
The project combines laboratory research, industrial-scale production and architectural design. Different biochar types and pre-processing methods will be evaluated to identify the optimal mix design, followed by mechanical and fire-resistance testing. The most promising solution will be scaled to industrial production and demonstrated through digital and physical architectural applications. The project will also document material performance through a life cycle assessment (LCA), assess market uptake and support dissemination alongside project management.
CHARBLOCK will deliver a carbon-negative LWCB validated at industrial scale, supported by full material documentation, a life cycle assessment (LCA) and digital and physical demonstrators. If fully implemented in Denmark, the solution has the potential to reduce CO2 emissions by up to 70,000 tonnes annually. The project strengthens Danish leadership in carbon-negative construction and creates new market opportunities for biochar producers and block manufacturers.
