基于二氧化碳热力循环的储能研究综述

Research summary on the energy storage technologies based on carbon dioxide thermodynamic cycle

基于二氧化碳热力循环的储能技术,结合二氧化碳循环的优良性能和捕集后二氧化碳的再利用需求,有望在未来以新能源为主体的能源体系中发挥出重要作用。针对基于二氧化碳循环的储能技术进行了定义,并依据各储能方案的技术特点将该储能划分为电热储能,低、中和高压储气的压缩二氧化碳储能,低温和近常温储液的压缩二氧化碳储能,以及恒压储气的压缩二氧化碳储能;讨论了各类储能技术的研究现状、具有的优势和存在的不足。低压储气的压缩二氧化碳储能技术最为成熟,目前已有大型工程示范机组建成;高压储气的压缩二氧化碳储能和大规模电热储能的综合性能较好,但成本较高;低压端储存液态二氧化碳的压缩二氧化碳储能的循环效率最低,但储能密度最高;恒压储气的压缩二氧化碳储能效率最高,可达74%~76%,储能密度接近2(kW·h)/m^(3),是极具发展前景的压缩气体储能技术之一。

Combing the excellent performance of carbon dioxide thermodynamic cycle and the reutilization demands for the captured carbon dioxide,the energy storagetechnologies based on carbon dioxide thermodynamic cycle have the potential to play an important role in the future energy system which mainly consists of renewable energies.This paper presents the definition of the energy storage technology based on carbon dioxide thermodynamic cycle,and then classifies this energy storage technology into six types,which are electrothermal energy storage,compressing carbon dioxide energy storage with low,mid and highpressure gas storage,compressing carbon dioxide energy storage with low-temperature and near atmospheric temperature liquid storage,and the constant pressure gas storage energy storage.The state-of-the-art research status,advantages and disadvantages of these technologies are discussed.In general,the compressing carbon dioxide energy storage with low pressure gas storage is most mature,and there are demonstration units constructed.The compressing carbon dioxide energy storage with high pressure gas storageand the electrothermal energy storage have a good overall performance,but their costs are high.The compressing carbon dioxide energy storage with constant pressure gas storage has the highest cycle efficiency,reaching 74%~75%,and the energy storage density is up to 2(kW·h)/m^(3),making it one of the most promising compressing gas energy storage technologies.