Biogenic CO2 capture into Sustainable Energy Carriers: A novel photosynthetic and hydrogenotrophic CO2 fixation combined with waste nutrient upcycling for production of carbon negative energy carriers

Project Information

COSEC

Grant agreement ID: 101172850

DOI

10.3030/101172850

EC signature date 8 August 2024

Start date 1 October 2024

End date 30 September 2027

Funded under

• Climate, Energy and Mobility

Total cost

€ 3 906 925,00

EU contribution

€ 3 906 925,00

Coordinated by

CYANOCAPTURE LTD
United Kingdom

Periodic Reporting for period 1 - COSEC (Biogenic CO2 capture into Sustainable Energy Carriers: A novel photosynthetic and hydrogenotrophic CO2 fixation combined with waste nutrient upcycling for production of carbon negative energy carriers)

Reporting period: 2024-10-01 to 2026-03-31

Summary of the context and overall objectives of the project

The project responds to the urgent need for scalable and sustainable solutions that can reduce greenhouse gas emissions while supporting the transition to a circular and low-carbon economy. Its overall objective is to develop and validate an integrated biological carbon capture and utilisation platform based on microalgae and cyanobacteria, able to capture CO2 from bioenergy effluent gases while simultaneously using waste-derived nutrients and converting the resulting biomass into valuable energy carriers and co-products. The project addresses several key challenges at once: the high cost of carbon capture, the need for more flexible and decentralised CCUS solutions, the competition for sustainable biomass resources, and the demand for technologies that can support the decarbonisation of agriculture, industry and transport.

The project pathway to impact is built around a closed-loop concept in which CO2, nutrients and residual streams are reused as efficiently as possible. Microalgae cultivation is being optimised to improve CO2 fixation and biomass productivity under real operating conditions, including flue gas exposure and wastewater use. The biomass is then converted into biogas and biocrude, while residual fractions are explored for further valorisation. This approach is expected to contribute to the development of cost-effective CCUS value chains, strengthen Europe’s technology leadership in biological carbon capture and utilisation, and support the Green Deal, REPowerEU and net-zero objectives through low-carbon fuels, resource efficiency and circularity.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the reporting period, the consortium made substantial progress in developing the technical basis of the COSEC solution. On the capture side, reactor optimisation studies improved mixing, light utilisation and process control in raceway systems, while online monitoring tools were validated to track performance under outdoor conditions. Several microalgal and cyanobacterial strains were screened and tested for resilience to flue gas and nutrient-rich effluents, and the most promising strains were identified for further scale-up and outdoor validation.

On the conversion side, biomass characterisation showed that ash content remains a major technical constraint for hydrothermal liquefaction, and batch as well as continuous HTL tests were used to define suitable operating conditions. The results showed that higher temperatures and shorter residence times improved biocrude performance, although further improvement of biomass quality is still needed. Anaerobic digestion trials showed stable methane production with unprocessed biomass, and the thermophilic system delivered slightly higher performance than the mesophilic one. Preliminary upgrading studies have also started, including the evaluation of HTL biocrude for hydrotreatment and the use of hydrochar as a catalyst support for renewable hydrogen-related applications.

In parallel, pilot-scale integration work progressed through process flow definition, equipment design, and preparation for permitting and site implementation. Overall, the project has already delivered clear scientific and technical results, while also identifying the main bottlenecks that must be addressed to enable robust scale-up.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The project has generated results that go beyond the state of the art in several ways. First, it has demonstrated that microalgae raceway systems can be improved through hydrodynamic modifications, adaptive control and real-time monitoring, enabling higher CO2 fixation efficiency without increasing energy demand. Second, it has shown that waste streams can be used as nutrient sources, supporting a more circular and economically attractive cultivation model. Third, it has advanced strain selection for robustness under industrially relevant conditions, combining high lipid content with tolerance to flue gas and nutrient-rich effluents.

The project has also shown that downstream conversion performance depends strongly on feedstock quality, particularly ash content, which has important implications for future biomass specification and process design. The combined work on HTL, anaerobic digestion and upgrading provides a more integrated understanding of how algal biomass can be converted into energy carriers and co-products. Further uptake will depend on continued pilot-scale validation, better feedstock standardisation, access to scale-up investment, and continued work on upgrading, materials integration and techno-economic assessment. Strengthening market readiness and regulatory alignment will also be important for future deployment.