Thermodynamic Evaluation and Sensitivity Analysis of a Novel Compressed Air Energy Storage System Incorporated with a Coal-Fired Power Plant

Abstract

A novel compressed air energy storage (CAES) system has been developed, which is innovatively integrated with a coal-fired power plant based on its feedwater heating system. In the hybrid design, the compression heat of the CAES system is transferred to the feedwater of the coal power plant, and the compressed air before the expanders is heated by the feedwater taken from the coal power plant. Furthermore, the exhaust air of the expanders is employed to warm partial feedwater of the coal power plant. Via the suggested integration, the thermal energy storage equipment for a regular CAES system can be eliminated and the performance of the CAES system can be improved. Based on a 350 MW supercritical coal power plant, the proposed concept was thermodynamically evaluated, and the results indicate that the round-trip efficiency and exergy efficiency of the new CAES system can reach 64.08% and 70.01%, respectively. Besides, a sensitivity analysis was conducted to examine the effects of ambient temperature, air storage pressure, expander inlet temperature, and coal power load on the performance of the CAES system. The above work proves that the novel design is efficient under various conditions, providing important insights into the development of CAES technology.

Global Sensitivity Analysis Based on Entropy: From Differential Entropy to Alternative Measures

“…If the lower bound of the domain of f (r) is greater than µ R − 10σ R , then integration is performed from the lower bound of f (r). Numerical integration is not used for Sobol sensitivity indices, which are computed analytically using Equation (22). Cramér-von Mises sensitivity indices are estimated using the algorithm described in [39,69], with the difference that three input random variables are used in this article.…”

“…Another group of tasks uses entropy to examine the state of a system in combination with certain types of SA, which may not be based on entropy. This group includes, for example, SA of the working process of heat exchangers [18], the hydraulic reliability of water distribution systems [19], shear stress distribution in a rectangular channel [20], creep of soft marine soil [21], air energy storage systems in coal-fired power plants [22], uncertainties of mathematical decision-making models [23][24][25][26][27], and many others.…”

Performance enhancement and optimization of primary frequency regulation of coal‐fired units under boundary conditions

“…[10][11][12] The primary frequency modulation response performance of thermal power units is affected by a variety of factors, such as signal acquisition, control strategy, and nonlinearity of the speed control mechanism. Pan et al 13 analyzed 10 MW case system integrated with a 350 MW thermal power unit. Gao et al 14 establish the mechanism model under different operating conditions and analyze the dynamic characteristics of the ultra-supercritical unit.…”