What is compressed air energy storage (CAES)?

Compressed air energy storage (CAES) is an effective solution for balancing this mismatch and therefore is suitable for use in future electrical systems to achieve a high penetration of renewable energy generation.

Where can compressed air energy be stored?

The number of sites available for compressed air energy storage is higher compared to those of pumped hydro [, ]. Porous rocks and cavern reservoirs are also ideal storage sites for CAES. Gas storage locations are capable of being used as sites for storage of compressed air .

What is a compressed air energy storage expansion machine?

Expansion machines are designed for various compressed air energy storage systems and operations. An efficient compressed air storage system will only be materialised when the appropriate expanders and compressors are chosen. The performance of compressed air energy storage systems is centred round the efficiency of the compressors and expanders.

What is a compressed air storage system?

The compressed air storages built above the ground are designed from steel. These types of storage systems can be installed everywhere, and they also tend to produce a higher energy density. The initial capital cost for above- the-ground storage systems are very high.

Why do we need compressed air energy storage systems?

With excellent storage duration, capacity, and power, compressed air energy storage systems enable the integration of renewable energy into future electrical grids. There has been a significant limit to the adoption rate of CAES due to its reliance on underground formations for storage.

Why do compressed air energy storage systems have greater heat losses?

Compressed air energy storage systems may be efficient in storing unused energy, but large-scale applications have greater heat losses because the compression of air creates heat, meaning expansion is used to ensure the heat is removed [, ]. Expansion entails a change in the shape of the material due to a change in temperature.