The DAC-Battery project aims to develop and demonstrate an integrated system that captures atmospheric CO2 while simultaneously providing grid-balancing services through hydrogen production, storage and consumption. The project is based on the hypothesis that combining a novel, passive, membrane-assisted Direct air capture (DAC) system with a reversible alkaline fuel cell/electrolyser (H-Battery) can significantly reduce the levelised cost of CO2 capture to USD 250/tonne, well below current DAC costs. This dual-functional system is expected to close the price gap between sellers and buyers in carbon credit markets, enabling large-scale deployment of DAC.
The project involves the development and integration of two core innovations: a passive, membrane-based DAC unit and the H-Battery. The DAC unit will be scaled from a TRL 3 prototype to a TRL 5 pilot system. The H-Battery will be scaled from TRL 2 to a 2 kW TRL 4 stack capable of switching between electrolysis mode – regenerating the DAC sorbent and producing hydrogen – and fuel cell mode – generating electricity from stored hydrogen. These components will be integrated and tested for compatibility, performance and durability, with system-level modelling conducted using EnergyPRO to simulate real-world operation under Danish energy market conditions. The project also includes techno-economic analysis, policy evaluation and stakeholder engagement to support market readiness and alignment with national climate goals.
The DAC-Battery project is expected to deliver a TRL 5 prototype that integrates CO2 capture with hydrogen-based energy storage, targeting a CO2 capture cost of USD 250/tonne. It will enable flexible grid services, support renewable energy integration and contribute to Denmark’s 2045 climate neutrality goals. The system offers a scalable, economically viable solution for carbon removal and energy storage, with strong commercialisation and job creation potential.
