Compressed Air Energy Storage

CAES

We are your compressed air energy storage solution provider

Siemens Energy CAES is a comprehensive, proven, grid-scale energy storage solution. We support projects from conceptual design through commercial operation and beyond. Our CAES solution includes all the associated above ground systems, plant engineering, procurement, construction, installation, start-up services and long term service support.

Product Information

What makes Siemens Energy CAES the preferred choice?

Siemens Energy CAES improves utilization of renewable energy resources by absorbing GW-hours of energy that would otherwise be curtailed and provides grid balancing and reserve services with lower fuel usage and carbon footprint than other controllable resources.
Compressed Air Energy Storage Whitepaper

A proven solution for cost-effective, grid-scale, and long-duration power storage

As renewable power generation from wind and solar grows in its contribution to the world’s energy mix, utilities will need to balance the generation variability of these sustainable resources with demandfluctuations. This paper describes how power-generation operators can use compressed air energy storage (CAES) technology for a reliable, cost-effective, and long-duration energy storage solution at grid scale. Further, it explains how CAES can provide a path to deep grid decarbonization via hydrogen as fuel. 

Overview

Cycle Overview

Portfolio

Proven components packaged for a new market

Benefits

Benefits

  • Responds quickly - Designed to be started and brought to full load in less than 10 minutes, eliminating the need for intermediate-load plants and providing a cost-effective way to meet spinning reserve requirements. 
  • CAES generation also has excellent load-following capability and exceptional part-load efficiency. 
  • Full compression can be available in less than five minutes to quickly absorb load rather than reducing your base load generation.
  • Flexible cycling options - The CAES plant allows for independent operation of the compression and expansion systems, allowing for simultaneous load absorption and balancing.
  • Generation efficiency - Relatively flat heat rate across all operating ranges, thus overall generation efficiency is near the same at 10 percent as it is at 100 percent.
  • Days of storage - The intermittency of renewables coupled with unpredictable weather patterns means the reality of long periods where balancing is paramount to absorbing renewables. 
aCAES

CO2 and NOx emission free CAES

The proven technologies of the large air compressors, thermal storage systems and a turbine-driven generator ensure an energy storage, which is 100% free of CO2 and NOx emissions.

Adiabatic CAES cycle with thermal storage

  1. Electricity, preferable from renewable sources, is used for the air compression, which heats the air in the same time.  
  2. The compressed air is stored in existing caverns, e.g. in emptied salt caverns, mines, re-used gas pipes, etc. Worldwide many of these storage options exist.
  3. Via the thermal storage and heat exchanger the decharge cycle is activated. An expander (turbine) driven generator converts this cycle back in electricity.

Applications

CAES is the ideal solution for energy and ancillary services including:

  • Load leveling / balancing
  • Ramping regulation
  • Frequency oscillation
  • Transmission optimization
  • VAR support

Performance Summary

Power Output

System Flow

LHV Heat Rate

LHV Fuel Usage

MW
lbm / s
BTU / kWh
lbm / s
160
317
3855
8.5
105
226
3881
5.6
85
199
3906
4.6
65
168
3940
3.5
50
147
3980
2.7
35
116
4035
1.9
20
87
4208
1.2
16
73
4254
0.9