Multi-Objective Analysis of a CHP Plant Integrated Microgrid in Pakistan

Asad Waqar,Muhammad Shahbaz Tanveer,Fareeha Anwar,Jehanzeb Ahmad,Muhammad Aamir,Muneeb Yaqoob

doi:10.3390/en10101625

Abstract

In developing countries like Pakistan, the capacity shortage (CS) of electricity is a critical problem. The frequent natural gas (NG) outages compel consumers to use electricity to fulfill the thermal loads, which ends up as an increase in electrical load. In this scenario, the authors have proposed the concept of a combined heat & power (CHP) plant to be a better option for supplying both electrical and thermal loads simultaneously. A CHP plant-based microgrid comprising a PV array, diesel generators and batteries (operating in grid-connected as well as islanded modes) has been simulated using the HOMER Pro software. Different configurations of distributed generators (DGs) with/without batteries have been evaluated considering multiple objectives. The multiple objectives include the minimization of the total net present cost (TNPC), cost of generated energy (COE) and the annual greenhouse gas (GHG) emissions, as well as the maximization of annual waste heat recovery (WHR) of thermal units and annual grid sales (GS). These objectives are subject to the constraints of power balance, battery operation within state of charge (SOC) limits, generator operation within capacity limits and zero capacity shortage. The simulations have been performed on six cities including Islamabad, Lahore, Karachi, Peshawar, Quetta and Gilgit. The simulation results have been analyzed to find the most optimal city for the CHP plant integrated microgrid.

Highlights

During the winter season in Pakistan, natural gas (NG) is used as a primary source to supply the thermal load in the form of heating [1]
Start using electricity due to outage of natural gas. This supply of thermal load by the electricity was putting an extra burden on the electricity grid
The authors have proposed a solution in the form of a combined heat and power (CHP) plant integrated microgrid to supply both electrical and thermal loads simultaneously

Summary

Introduction

During the winter season in Pakistan, natural gas (NG) is used as a primary source to supply the thermal load in the form of heating [1]. As there is an average capacity shortage (CS) of around 27% in electricity, the supply of thermal load by electricity puts an extra burden on the grid [2]. In such a situation, a microgrid along with a combined heat and power (CHP) plant represents a sensible solution to utilize the wasted heat and improving the efficiency to 75–88% [3,4,5,6,7,8]. A CHP plant recovers the wasted heat by using a waste heat recovery (WHR) unit, and helps in controlling the greenhouse gas (GHG)

Objectives

Results

Conclusion