Mechanical Behavior of a Pile Used for Small-Scale Compressed Air Energy Storage

Intermittent availability of renewable energy sources requires an energy storage system, and small-scale compressed air energy storage (CAES) has been brought up as an attractive option to store excess energy as a pressurized air. Here, we explore the idea of using a close-end steel pile as a vessel to store pressurized air. Small-scale CAES pile is expected to experience unusually a large number of cyclic loading during the operation. This paper frameworks the preliminary results from lab- and field-scale finite element simulations: plane-strain and axisymmetric models are adopted to examine mechanical behavior of a steel pile during a loading-unloading cycle by internal air pressure. Computational models include simple constitutive models of pile, soil, and pile-soil interface. Preliminary results reveal the stability condition of CAES pile as well as deformation pattern.