학술논문

Thermodynamic analysis of a compressed carbon dioxide energy storage system using two saline aquifers at different depths as storage reservoirs
Document Type
article
Source
Subject
Subsurface energy storage
Compressed CO2 energy storage system
Utilization of CO2
Two saline aquifers reservoirs
Thermodynamic analysis
Parametric analysis
Energy
Electrical and Electronic Engineering
Mechanical Engineering
Language
Abstract
Compressed air energy storage (CAES) is one of the leading large-scale energy storage technologies. However, low thermal efficiency and low energy storage density restrict its application. To improve the energy storage density, we propose a two-reservoir compressed CO2 energy storage system. We present here thermodynamic and parametric analyses of the performance of an idealized two-reservoir CO2 energy storage system under supercritical and transcritical conditions using a steady-state mathematical model. Results show that the transcritical compressed CO2 energy storage system has higher round-trip efficiency and exergy efficiency, and larger energy storage density than the supercritical compressed CO2 energy storage. However, the configuration of supercritical compressed CO2 energy storage is simpler, and the energy storage densities of the two systems are both higher than that of CAES, which is advantageous in terms of storage volume for a given power rating.