What is compressed air energy storage (CAES)?

1. Introduction Compressed Air Energy Storage (CAES) has emerged as one of the most promising large-scale energy storage technologies for balancing electricity supply and demand in modern power grids. Renewable energy sources such as wind and solar power, despite their many benefits, are inherently intermittent.

How does compressed air energy storage work?

Typically, compressed air energy storage (CAES) uses surplus, low-cost electrical energy (e.g. from renewable power generation) and stores it safely as compressed air, often in underground caverns. Whenever the energy is needed, that stored energy can generate electricity for the grid by passing the air through a turbine.

Where is compressed air stored?

Storage: The compressed air is stored, typically in large underground caverns such as salt domes, abandoned mines, or depleted natural gas reservoirs. Above-ground alternatives include high-pressure tanks or specially designed vessels, though these are generally more expensive and limited in capacity.

Is large-scale storage a viable source of peak power and ancillary grid services?

Over the years, it has proven a stable source of peak power and ancillary grid services for the region. Completed in 2012, the Gaines CAES project in Texas (500 MW) further demonstrated the viability of large-scale storage in salt formations.

What are the benefits of a CAES energy storage system?

• Off-Grid Energy Storage: In remote locations with ample renewable resources but unreliable grids, CAES can store surplus solar or wind energy for use during peak demand, reducing reliance on diesel generators. • Long-Duration Storage: Eco-resorts often require consistent power for lighting, HVAC, and guest services.

Is CAES a long-term energy storage solution?

By 2012, with the Gaines, Texas, project (500 MW capacity) and other pilot programs, the idea of CAES as a large-scale, long-duration energy storage solution gained traction.