Techno-economic Analysis of Different Liquid Air Energy Storage Configurations

Abstract

With the increasing use of renewables in energy systems, grid stability becomes a major issue due to the intermittent nature of energy sources such as solar and wind. To compensate for the unstable renewable energy sources, storage technologies have been regarded as effective methods. Liquid air energy storage (LAES) has gained wide attention due to its inherent advantages: geographically unconstrained and high energy density. This work presents a techno-economic analysis of an LAES system with a storage capacity of 10 MW / 80 MWh. Three different layouts of the LAES are evaluated and compared based on net present value (NPV) and payback period. The economic results show that the LAES system with a 2-stage compressor and a 3-stage expander (Case 1) has the largest NPV of 918.1 M$, which is 33.7 % and 10.7 % larger than a system with a 4-stage compressor and a 4-stage expander without (Case 2) / and with (Case 3) an additional Organic Rankine Cycle (ORC). In addition, the shortest payback period of 6.2 y is obtained in Case 1 compared to 6.9 and 6.4 y for Cases 2 and 3. This means that Case 1 is the most profitable layout for the studied LAES systems.