The Optimal Operation Criteria for a Gas Turbine Cogeneration System

Yasushi Ishida,Yasushi Harada,Ryuichi Yokoyama,Takahiko Miyazaki,Atsushi Akisawa,Masaaki Bannai

doi:10.3390/en20200202

Yasushi Ishida, Yasushi Harada + Show 4 more

Open Access

https://doi.org/10.3390/en20200202

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Abstract

The study demonstrated the optimal operation criteria of a gas turbine cogeneration system based on the analytical solution of a linear programming model. The optimal operation criteria gave the combination of equipment to supply electricity and steam with the minimum energy cost using the energy prices and the performance of equipment. By the comparison with a detailed optimization result of an existing cogeneration plant, it was shown that the optimal operation criteria successfully provided a direction for the system operation under the condition where the electric power output of the gas turbine was less than the capacity

Highlights

Cogeneration, or combined heat and power production, is suitable for industrial users who require large electricity as well as heat, to reduce energy and environmental impact
The purpose of our study is to provide criteria for optimal operation of gas turbine cogeneration systems including turbine inlet air cooling
The study demonstrated the optimal operation criteria of a gas turbine cogeneration system based on the analytical solution of a linear programming model

Summary

Introduction

Cogeneration, or combined heat and power production, is suitable for industrial users who require large electricity as well as heat, to reduce energy and environmental impact. The second one is the case where the electric power from the gas turbine is at the maximum, which means xGT = XGT + αGT xAC We denominate the former and the latter conditions the operational conditions I and II, respectively. After the case C, the electric power from the gas turbine is positive at the optimal operation. The optimal solution does not exist because the reduction of the gas cost is unlimited by the inlet air cooling using the absorption chiller driven by the boiler. It is obvious that the mode c has to be chosen if the steam to electricity ratio of the gas turbine is equal to the ratio of the heat flow rate of the steam demand to the electric power demand, i.e. ρGT = xs /xe.

20 C o o 10 oC 30 C

Conclusions