Integration of small-scale compressed air energy storage with wind generation for flexible household power supply

Abstract

Energy storage can help regulate energy supply and demand and facilitate utilization of distributed renewable energy. Compressed Air Energy Storage (CAES) can store surplus energy from wind generation for later use, which can help alleviate the mismatch between generation and demand. In this study, a small-scale CAES system, utilizing scroll machines for charging and discharging, was developed to integrate into a wind generation for a household load. A simulation model, which was verified by our experiments results, was constructed for investigating the performance of the small-scale energy storage system. The operation map of the expander was obtained through the simulation for illustrating the expander's optimal parameters. A fluctuating wind generation profile was integrated into the small CAES to supply adjustable electricity. The dynamic performance of key components including compressor, expander and storage tank was assessed for the first time for a practical application. The results revealed that distributed renewables with an energy storage system become flexible and such integration can help satisfy fluctuating power demand. Efficiency of energy utilization, which was defined as the percentage of energy consumption to wind generation in a typical day, achieved a value as high as 88.75%. At the same time, maximal installation of generating capacity coupled with the integration of the CAES system was reduced by 15%.