The growing share of intermittent renewable energy, such as wind and solar power, is forcing fossil fuel-based power plants to operate with daily load changes and even with relatively long shut-down periods. This flexible type of operation should also be expected for power plants equipped with CO2 capture and storage (CCS) facilities as such plants will co-exist in countries with a high share of renewables. The flexible operation is being increasingly recognized as a major obstacle to the development and deployment of CCS.

From a technical point of view, the load changes in power plants with CCS are more challenging than in conventional power plants due to the higher degree of complexity and integration between the different sub-systems. Therefore, already well-developed CO2 capture technologies have to be advanced and demonstrated regarding their flexibility potential. A common approach to improve the flexibility of these technologies is to postpone the energy penalty associated to the capture process towards low demand periods.

FlexiCaL aims to develop novel Calcium looping systems able to respond to a wide range of flue gas load changes. The flexibility of dual fluidized bed flexibility and approaches for decoupling of the solid circulation between reactors from the flue gas load to the carbonator will be analyzed in the FlexiCaL project. In addition, a new concept including an energy storage system into the boundaries of the CaL system will be tested.