New Research on Near-Isothermal Compressed Air Energy Storage in Aquifers Offers Promising Findings for Renewable Energy

Strategic Insights -

Researchers from the University of Sydney have conducted a new study on near-isothermal compressed air energy storage in aquifers, revealing promising findings for intermittent renewable energy sources such as wind and solar power. The study found that the round-trip efficiency of the I-CAES system can reach up to 67% in highly permeable regions, without the need for fuel combustion. The research also demonstrated that there is no need to reheate expanded air with the proposed near-isothermal machinery, which is significantly advantageous compared to conventional diabatic-CAES.

Key Takeaways:

  • The study used a new framework for assessing the performance of I-CAES in aquifers based on a coupled surface plant-wellbore-reservoir 3D model, in conjunction with machine learning and uncertainty analysis.
  • The research adopted the existing geological database and used geostatistical analysis to investigate the feasibility of I-CAES in the Gippsland Basin in Southeastern Australia.
  • The study found that aquifer depth and permeability are the most significant geological factors affecting the output power and round-trip efficiency of the I-CAES system.
  • The uncertainty analysis indicated that the daily storage potential in Gippsland Basin is found to range from 0.88 to 1.48 TWh, with a corresponding probability of from 90% to 10%, which is equivalent to 116%-181% of the daily Australian electricity consumption in 2023.
  • The proposed near-isothermal machinery eliminated the need for reheating expanded air, which is a significant advantage compared to conventional diabatic-CAES.

Statistics:

  • Round-trip efficiency of the I-CAES system can reach up to 67% in highly permeable regions.
  • The daily storage potential in Gippsland Basin ranges from 0.88 to 1.48 TWh.
  • The corresponding probability of the daily storage potential ranges from 90% to 10%.
  • The daily Australian electricity consumption in 2023 is equivalent to 116%-181% of the storage potential in Gippsland Basin.

Sources:

  • Performance and Feasibility Assessment of Near-isothermal Compressed Air Energy Storage In Aquifers. Journal of Cleaner Production, 2025;523.
  • Elsevier Sci Ltd (London, England).
  • Luming Shen et al. (University of Sydney).
  • Zifeng Cheng, Daniel Dias-da-Costa, Yixiang Gan, and Sheng Jiang (additional authors).