Research On Operating Mechanisms Of Energy Performance Contracts (EPCs) Of Commercial Building Energy Efficiency Retrofits

With the acceleration of the urbanization process,China is facing a severe resource and under an environmental situation.Building energy consumption accounts for a high proportion of the total energy consumption in the society.At present,China’s economic growth has entered a new normal,which brings a great challenge to energy transformation and reform.In 2020,China was striving to achieve a carbon peak by2030 and carbon neutrality by 2060.In order to achieve the "double-carbon" goal in the construction field,it is necessary to continuously strengthen the energy saving management of public buildings,actively innovate the market mechanism of energy efficiency and promote market-oriented transformation modes such as Energy Performance Contracts(EPCs).However,the industry of energy conservation services in China is still in the initial stage.There are certain limitations in the implementation of EPCs in the sector of buildings.Therefore,this research focuses on the improvement of EPCs in the sector of energy efficiency retrofits of commercial buildings.The purpose of this research is committed to realizing a stable and predictable sustainable market mechanism.Based on the theory of mechanism design,this research is designed to answer three research questions: how to select a suitable EPC operational model,how to design an EPC contract period and allocate benefits and how to design an EPC risk management mechanism.Firstly,a method of selecting an operational model of EPCs is put forward.The influencing factors of the selection of the operational model of EPCs are analyzed.From the technical level,a selection method of energy efficiency technical scheme is established based on the concept of life-cycle costs.Based on this,a systematic decision model is developed from the technical level to the investment level.A set of decisionmaking indicators is established based on technical and economic perspective,comprehensive risk preference,financing ability and external policy environment.Then a method of quantitative decision-making indicators with a fuzzy interval value intuition set is put forward.Therefore,the operational selection model based on the method of TODIM-IVIFS is established and validated by a case study.Secondly,a mechanism of EPC benefit allocation combining contract period decisions is established.A framework of the decision-making of EPC contract period and benefit allocation is constructed,which fully considers the internal connection between contract period design and energy saving benefit allocation.The key indicators of decision function are established accordingly.By maximizing the net present value for energy service companies and building owners separately,a feasible interval of the contract period is set.In order to realize the elastic design of the contract period,an option game model is introduced to distribute the option value of the contract period.Based on this,a comprehensive fuzzy physical option decision model of the contract period is established.Finally,a Stackelberg-Shapley model is designed to allocate energy saving benefits.It aims to simulate the process of the negotiation and the contract design within building owners and energy service companies.By making the linkage with the contract period and considering the influencing factors of benefit allocation,a modified Shapley Value model is established to optimize the coefficient of benefit allocation.The feasibility of the method is demonstrated through a case study.Lastly,a risk management mechanism for EPCs is established.Based on the incomplete contract theory,a theoretical framework of EPC dynamic risk management is established.According to the implementation stages of EPCs,a three-stage risk allocation of EPCs is designed accordingly.The three stages are the initial risk management scheme design,overall risk sharing and risk response and risk dynamic management.Based on the theoretical framework,EPC risk factors are identified and analyzed through literature review,semi-structured interviews,thematic analysis and the correction of the bow-tie model.Then quantitative data are collected through the questionnaire survey and analyzed by principal component analysis yielding seven main risk factors.These seven main risks are used to establish the structural equation model and validate the risk transmission path of EPCs.The results show that external risks(policy and market risks);internal risks(contract and operational risks)are the key risks in EPCs,which have a vital impact on the final energy saving benefits.Then,the dynamic risk allocation adjustment is realized through the cooperation performance of the contracting parties and external risk impact established by the prosed prospect value model.Finally,the risk control and prevention mechanism of EPCs are proposed.The innovation of this study is shown in the following aspects:(1)An all-factor EPC operational model selection method is put forward based on Prospect Theory.Firstly,a method of selecting a technical scheme of energy efficiency retrofits is established based on the concept of life-cycle costs.By using Interval-valued Intuitionistic Fuzzy Sets,the decision criteria are determined from the technical level to the investment level secondly.An all-factor selection method of the operational model is developed based on technical and economic perspectives,comprehensive risk preference,financing ability and external policy environment.It applies TODIM in assisting decision-makers in selecting EPC operational models.By using the objective CRITIC weight calculation method,the limitation of thematic analysis is made up and the impact of the interaction between factors on the model selection is decreased.By integrating the CRITIC weights and the new fuzzy entropy,the relative weight of this method is improved.As the result,the weight calculation method of factors influencing the selection of EPC operational models is improved.(2)A benefit allocation method of EPCs is proposed based on a flexible decision mechanism of the contract period.This method involves the internal connection and interactive influence of contract period design and energy saving benefit allocation of EPCs.The purpose is to design a flexible contract for EPCs.Starting from maximizing the net present value of energy saving benefits,a fuzzy physical option pricing model is introduced to design the contract period of EPCs under the Physical Option Theory.Based on this,a Stackelberg-Shapley model is established to allocate energy saving benefits that are linked with the decision of the contract period,which is to obtain the optimal contract period and benefit allocation scheme.This method aims to simulate the negotiation and decision-making relationship between building owners and the energy service companies.At the same time,it aims to achieve a cooperative-based and fair energy saving benefit allocation method to further encourage contracting parties in maximizing the energy saving benefits.(3)A dynamic optimization method of risk allocation of EPCs is proposed based on the Incomplete Contract Theory.By integrating Risk Management Theory and Incomplete Contract Theory,the theoretical framework of dynamic risk management of EPCs is developed,which lays a theoretical foundation for the research of the risk management mechanism of EPCs in commercial buildings.From this guidance,at the operational level,a three-stage of EPC allocation path road is developed.Based on a static one-time risk allocation,a multi-stage risk dynamic adjustment is made to predict and judge the evolution status of risk events during the operation of the EPC projects.By using the dynamic optimization method,the prospect value model is established to dynamically adjust the original static risk allocation model through the internal cooperative performance of contracting parties and the external risk changes.