Optimization Research On Rural Heat Storage Solar-Air Source Heat Pump System

Under the pressure of the energy crisis and the background of carbon peaking and carbon neutrality,the development and utilization of renewable energy has received extensive attention.Reasonable application of clean energy represented by solar energy for building heating has become an effective measure to improve winter environmental pollution and alleviate energy pressure.Especially in rural areas in northern China,the winter heating method is mostly decentralized heating,and the combustion of loose coal has caused serious environmental pollution,greatly reducing the quality of life of rural residents.The heating form urgently needs improvement.This article proposes a heat storage solar air source heat pump system for winter heating in northern rural areas,which can simultaneously meet the needs of winter heating and domestic hot water.This article analyzes and studies the characteristics of the system’s application in rural residential buildings in northern China through a combination of theoretical research,experiments,and computer simulation.It optimizes the system design combination,improves the system’s operational control level,and provides technical support for the efficient utilization of renewable energy heating technology in rural residential buildings.Firstly,this thesis selects a typical residential building in the rural area of Jinan City,Shandong Province as the research object.Combining with the general situation of the building,a typical residential architectural model model is established and the hourly heat load in the heating season is calculated using TRNSYS software.A set of thermal storage solar air source heat pump system was developed and designed based on the load calculation results,and preliminary selection was carried out.A mathematical model of key components was established based on the system principle and composition,and a TRNSYS simulation model of the system was built to lay the foundation for performance research and optimization design.Secondly,a system test bench was built based on the selection results,and a typical day was selected for experimental testing to verify the performance and heating effect of the thermal storage solar air source heat pump system,as well as the accuracy of the computer TRNSYS simulation model built.The results show that the average heat collection efficiency of a typical day is 67%,the average heating performance coefficient of an air source heat pump unit is 2.6,the solar energy guarantee rate is 45.62%,and the system energy efficiency ratio is 3.49.The comparison between experimental and simulation data shows that the average deviation between the two is within 10%.Based on the comprehensive analysis,the overall system can meet the heating demand and the operating effect is ideal.The simulation model built has high accuracy,It can be used for performance simulation research and optimization design research.Finally,the TRNSYS simulation model was used to optimize the design,selection,and operation strategies of key components in the system.By using the orthogonal experimental method to study the degree of influence of various influencing factors on the objective function,four influencing factors,namely collector area,collector inclination angle,rated heating power of the heat pump,and volume of the heat storage water tank,were selected as the objective function with the annual value of the system cost as the objective function.Orthogonal experiments were conducted,and the sensitivity analysis results of each influencing factor were combined.GENOPT was used to call the Hooke Jeeves algorithm to establish an optimization model,with the annual value of the system cost as the optimization goal,Synchronous optimization was conducted on four variables:collector area,collector inclination angle,rated heating power of the heat pump,and volume of the heat storage water tank.The results showed that when the collector area was 20 square meters,the rated heating power of the heat pump was 9.5 k W,the collector inclination angle was 30°,and the volume of the heat storage water tank was 2 meters3。At this time,the annual cost of the system is the lowest,which is 7.90%lower than before optimization.Based on the economically optimal selection plan,a set of overall operating strategies suitable for the heating season of the system has been optimized and studied.After overall optimization,the average heating efficiency of the collector in the heating season of the system can reach 68%,and the average heating performance coefficient of the air source heat pump unit has increased by 17.74%compared to before optimization.The solar energy guarantee rate can reach 49.65%,and the average heating performance coefficient has increased by 7.7%compared to before optimization.After analyzing the energy-saving,environmental,and economic benefits of the optimized system,it was found that the system can save 562.34kgce of standard coal per year,reduce CO₂,SO₂,and dust emissions by 1388.98kg,5.62kg,and 11.25kg,respectively.Compared to the static investment payback period of 5.8 years for the original gas wall mounted boiler system,the advantages of energy-saving,environmental,and economic benefits are more obvious.The various research results indicate that the system technology designed and developed in this article has strong adaptability and is economically and environmentally friendly.The optimized system performance has been significantly improved,providing a reference for the engineering application of thermal storage solar air source heat pump systems in northern rural areas.It is of great significance in helping to achieve the carbon peak goal of the rural revitalization strategy.