| The development of society and economy have been greatly promoted by the extensive utilization of fossil fuels. Meanwhile, some environmental and energy issues appear. The troubles of the large-scale utilization of fossil fuels could be alleviated effectively by developing renewable energy. Electric power is a prerequisite and important guarantee for social development, which plays an important role in the national energy strategy. The increase of renewable energy in electricity industry generates extensive and far-reaching influence on the sustainable development of our country and society. Considering the intermittency and instability of renewable energy, the ratio and scale of renewable energy are limited to avoid the fluctuation of the grid. Development and application of large-scale energy storage system is one of the most effective ways to alleviate the problems. Compressed air energy storage(CAES) with larger storage capacity, higher cycle efficiency and better operational stability has drawn more and more attention. Based on conventional CAES, the advanced adiabatically compressed air energy storage(AA-CAES) has been commercialized successfully since 1978. Thermal energy storage(TES) device is applied in the AA-CAES system to store the heat during the compression process, which consumes none fossil fuels and achieves zero-emissions. Currently, AA-CAES technology is considered as a promising method for energy storage.To calculate the performance parameters of the AA-CAES system more accurately and investigate the variations of temperature and pressure in air chamber during the cycle process, a more practical constant wall-temperature storage model was proposed, and the thermodynamic model of AA-CAES system was built based on the first law of thermodynamics and ideal gas equations. The performance of the system was calculated at a given input/output power by the model. The cycle efficiency of the system was analyzed separately under conditions of different pressure ratio of storage chamber, various heat transfer coefficients and diverse intervals. The temperature and pressure variations of the air chamber were revealed during steady cycle. In addition, the operating parameters of the 100 MW recuperative AA-CAES power plant were designed based on the results of thermodynamic calculation. The economic characteristic of the AA-CAES power plant was analyzed. The cost of construction and operation of the plant was estimated, and the comprehensive benefit and cash flow during its life span were calculated. The effect of various storage electric prices and operating time on the economy of the power plant was analyzed respectively. The relationship between recovery period and sale price was discussed with different purchase prices, which may provide references for the feed-in tariff to a certain extent. |
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