Analytical Off-design Characteristics of Gas Turbine-Based CCHP System

作者:Yang Cheng*; Huang Zhifeng; Yang Zeliang; Ma Xiaoqian
来源:7th International Conference on Applied Energy (ICAE), 2015-03-28 To 2015-03-31.
DOI:10.1016/j.egypro.2015.07.528

摘要

Grounded on the typical analytical off-design performances of some basic CCHP (combined cooling, heating and power) components, off-design characteristics of a gas turbine-based CCHP system were analyzed and summarized. The results and discussion show that, at full power load of the gas turbine, the CCHP relative cold output Q(c)(r) varies from 0 similar to 1.2, and the corresponding relative heat output Q(h)(r) from 1 similar to 0. The CCHP system supplies 23.7% of the design cold capacity or 22.7% of the design heat capacity at empty power load. CCHP economic exergy efficiency and thermal efficiency both rise with the increase of power output, and trend towards a slight decline at a near-full cooling load of chiller. In a wide operation range of CCHP, economic exergy efficiency and thermal efficiency both rise with the increase of cooling load. Higher ambient temperature results in lower relative capacity of cold, heat and power. It is proposed that renovation technologies such as gas turbine inlet air cooling, steam injected gas turbine and HRSG supplementary firing be applied to weaken the effect of the ambient temperature on CCHP system. The quantitative results are meaningful for optimal configuration and economical operation of the energy systems.