Evaluation of the biomass gasification-based combined cooling, heating and power system using the maximum generalized entropy principle

Abstract

In order to promote the environmental conservation and energy efficiency, sufficient attention has been paid to biomass gasification-based combined cooling, heating and power (BGBCCHP) systems. Accurate evaluation of BGBCCHP systems is helpful to improving its performance. The maximum generalized entropy principle was introduced to reveal the essential characteristics of BGBCCHP systems. The BGBCCHP system was regarded as an open and evolutionary information network. Annual total cost, annual primary energy consumption, annual carbon dioxide emissions and exergy efficiency were used as evaluation criteria. Reasonable weights were conferred to the criteria so as to make the system stable. Moreover, an evaluation model based on the maximum generalized entropy principle was established to determine the eigenvalues of the BGBCCHP system. Self-organizing feature map network was used to simulate the evaluation model of the BGBCCHP system. A case study based on an office building in Beijing, China, was carried out. Three operating strategies (following the thermal load, following the electric load and following the hybrid electric-thermal load) were considered in the evaluation of the BGBCCHP system. Sensitivity analysis was carried out to investigate the impact of economic and technical parameters on the evaluation results. Results indicated that the evaluation model based on the maximum generalized entropy principle could be used to evaluate the BGBCCHP system operated under different operating strategies. The BGBCCHP system operated following the electric load achieved the maximum eigenvalue, which showed that its best integrated performance. On the contrary, the BGBCCHP system operated following the thermal load achieved the minimum eigenvalue, which showed that its worst integrated performance. The impact of sensitivity factors on the eigenvalues of the BGBCCHP system was different, which showed that the integrated performance of the BGBCCHP system was closely related to such factors.