Integration of compressed air energy storage with wind turbine to provide energy source for combustion turbine generator

This paper provides a preliminary technical and economic assessment of a proposed wind farm where the wind turbines are coupled directly to air compressors to produce pressurized air. The pressurized air is stored in an underground facility and used as a continuous energy source for a combustion turbine generator system. This proposed system is a departure from the conventional approach of Compressed Air Energy Storage (CAES) where the air compressor is driven by grid power during off-peak periods and compressed air is discharged to drive the combustion turbine during high-peak demand periods. As part of the technical evaluation, a set of system requirements is established based on the Alabama Electric Cooperative (AEC) McIntosh CAES plant that has been in successful operation since early 1990´s. The technical analysis leads to the sizing of the CAES reservoir and the total wind turbine power requirement to produce 110 MW for 20-hr/day generation. A preliminary economic evaluation compares the levelized annual cost of the total plant against the potential annual revenue using an average locational marginal price (LMP) for the Midwest Independent System Operator (MISO) region. The paper concludes with a number of recommendations for further study.