Integrating variable renewable energy from wind farms into power grids presents challenges for system operation, control and stability due to the intermittent nature of wind power. One of the most promising solutions is the use of Compressed Air Energy Storage (CAES). The main purpose of this paper is to examine the technical and economic potential for use of CAES systems in the grid integration. To carry out this study, two CAES plant configurations: Adiabatic – CAES (A-CAES) and Diabatic - CAES (D-CAES) were modelled and simulated by using the process simulation software ECLIPSE. The nominal compression and power generation of both systems were given at 100MWe and 140MWe respectively. Technical results showed that the overall energy efficiency of the A-CAES was 65.6%, considerably better than that of the D-CAES at 54.2%. However, it could be seen in the economic analysis that the breakeven electricity selling price (BESP) of the A-CAES system was much higher than that of the D-CAES system at €144/MWh and €91/MWh, respectively. In order to compete with large scale fossil fuel power plants, we found that a CO2 taxation scheme (with an assumed CO2-tax of €20/tonne) improved the economic performance of both CAES systems significantly. This advantage is maximised if the CAES systems use low carbon electricity during its compression cycle, either through access to special tariffs at times of low carbon intensity on the grid, or by direct coupling to a clean energy source, for example a 100 MW class wind farm.
- Adiabatic compressed air energy storage
- Diabatic compressed air energy storage
- Process modelling
- Capital cost estimation
- Techno-economic analysis