Optimal Economic Modelling of Hybrid Combined Cooling, Heating, and Energy Storage System Based on Gravitational Search Algorithm‐Random Forest Regression

Abstract

The hybridization of two or more energy sources into a single power station is one of the widely discussed solutions to address the demand and supply havoc generated by renewable production (wind-solar/photovoltaic (PV), heating power, and cooling power) and its energy storage issues. Hybrid energy sources work based on the complementary existence of renewable sources. The combined cooling, heating, and power (CCHP) is one of the significant systems and shows a profit from its low environmental impact, high energy efficiency, low economic investment, and sustainability in the industry. This paper presents an economic model of a microgrid (MG) system containing the CCHP system and energy storage considering the energy coupling and conversion characteristics, the effective characteristics of each microsource, and energy storage unit is proposed. The random forest regression (RFR) model was optimized by the gravitational search algorithm (GSA). The test results show that the GSA-RFR model improves prediction accuracy and reduces the generalization error. The detail of the MG network and the energy storage architecture connected to the other renewable energy sources is discussed. The mathematical formulation of energy coupling and energy flow of the MG network including wind turbines, photovoltaic (PV), CCHP system, fuel cell, and energy storage devices (batteries, cold storage, hot water tanks, and so on) are presented. The testing system has been analysed under load peak cutting and valley filling of energy utilization index, energy utilization rate, the heat pump, the natural gas consumption of the microgas turbine, and the energy storage unit. The energy efficiency costs were observed as 88.2% and 86.9% with heat pump and energy storage operation comparing with GSA-RFR-based operation costs as 93.2% and 93% in summer and winter season, respectively. The simulation results extended the rationality and economy of the proposed model.

Cryogenic-Energy-Storage-Based Optimized Green Growth of an Integrated and Sustainable Energy System

“…In terms of multi-type energy supply, the battery is inferior to the CES system and does not have the function of multi-energy connection and supply. In addition, the battery has a short operational life and high replacement cost [17], which is not conducive to ensuring the cost of IES in the long-term operation time. In the third operational case, IES does not contain any auxiliary energy storage device.…”

“…Therefore, after the CES system is connected to IES, the flow of all kinds of energy is strengthened, the absorption of new energy is increased, and it is used to supply a variety of energy flow loads in a corresponding time [16]. The absorption capacity of wind power generation and solar power generation is studied in [17]. In the traditional cogeneration system, the conversion relationship between electric energy and other energy sources is only adjusted by conventional units, such as thermal power.…”

A Robust Economic Framework for Integrated Energy Systems Based on Hybrid Shuffled Frog-Leaping and Local Search Algorithm

“…Integrated energy systems coupling cold, heat, electricity, and gas energy, through the coordination and optimisation of each energy production, transmission, storage, conversion, distribution, and consumption, realise the cascade utilisation of energy, improve energy utilisation efficiency, and meet the diversified energy needs of industrial production and residential life [3,4]. In an integrated energy system, the energy storage unit is considered one of the core units because of its energy time-shifting function, which can improve the system's operating economy [5]. Among the existing energy storage technologies, adiabatic compressed air (ACA) can effectively enhance the operational flexibility of IES due to its advantages of long life, zero emissions and cold-, heat-, and electricity-fed combined power supply, and become an important solution for multi-energy coordination and comprehensive utilisation in an IES [6][7][8].…”