Adiabatic Compressed Air Energy Storage (ACAES) is a promising option for low-cost large-scale electricity storage. However, one problematic aspect of current ACAES designs is the requirement for variable pressure high-pressure air storage. Therefore, in this project we will investigate the phase change between liquid and vapour CO2 as a potential cushion to minimize the pressure change in the high-pressure air store during charge and discharge. This will require high heat transfer rates for removing and re-adding the latent heat of condensation and we will investigate both active and passive designs.
The project will involve design, experimental, and numerical work, with the proportion of each depending on the inclinations of the student. Potential project aims include (A) a detailed numerical simulation of the proposed system, including modelling the behaviour of the CO2 cushion and high-pressure air in the store, using the relevant Equations of State. (B) A robust design for the high-pressure air store to facilitate the necessary transfers of latent heat while maintaining air/CO2 separation. (C) Development of a laboratory-scale prototype. (D) Aspects of all three of the previous aims.