Decision-making Optimization Methodology And Its Applications Of Electricity System During The Low-carbon Transition

Electricity system is the core of the energy system and the driving force for socio-economic development.However,due to the coal-dominated generation structure in China,the rapid growth of electricity consumption has caused serious challenges for the energy security,climate change and environmental pollution.Therefore,it is of great significance to achieve a low-carbon transition of China's electricity system,so as to promote the economic growth,social stability and sustainable development.Targeting at the national low-carbon development strategy and the frontier of the energy economic system modeling,this dissertation employed a variety of methods to analyze the planning,investment,operation,market design,and regulation aspects of the low-carbon electricity system,which include the operations research,econometrics,Monte Carlo simulation and bibliometrics.During this process,the main research work and innovation are listed as below:(1)From the perspective of the socio-economic impacts of the power system development,the negative influence of different technologies' generation processes on the human and animal health,ecological diversity,crop output,and soil environment were quantified.Then,this dissertation established a low-carbon planning model for the electricity system which considers the negative external cost of different technologies.This has promoted the development of the current power planning theory and methods.Chinese electricity system planning during the period from 2015 to 2030 was selected to conduct the empirical research,the main findings shown that most of the new capacity additions come from the non-fossil fuel generation technology during this period,which accounts for 84%of the total capacity additions.Moreover,the fuel cost represents the largest share(45%)in the total cost.In addition,neglecting the external cost will significantly affect the planning results,which will reduce the amount of wind and gas-fired power capacity and increase the amount of coal-fired power capacity.(2)Introducing the break-even analysis method into the energy-saving cost supply curve model,an economic and energy-saving potential assessment model for the low-carbon technology portfolios was developed.Its advantage is that it can explore the feasibility of technology portfolios under the fuel price and carbon price uncertainties,moroever,it provides a new visualization research tool for analyzing the economics and potentials of technology portfolios.This model was used to analyze the energy conservation cost and potentials of 32 technologies in Chinese coal-fired power sector during the 13 th Five-Year Plan period.The main findings shown that the total coal saving potential from this technology portfolio is 276 Mt.Moreover,its economic feasibility is not good if only considering the energy conservation benefits,this is because its break-even coal price is866 yuan/ton.The Ultra Super Critical generation technology has the largest coal saving potential,while the the steam turbine performance improving technology has the lowest energy saving cost.Considering the co-benefits will increase the technology portfolio'economic feasibility,and the break-even coal prices will decrease by 2.35 yuan/ton when the carbon prices increase by 1 yuan/ton.(3)By setting the carbon prices under different climate policies as different random variables,the uncertainties of climate policy execution time,execution intensity,and execution methods was modeled.Then,an investment optimization model with consideration of the climate policy uncertainties was established using the stochastic dynamic programming method.This model could provide theoretical and methodological support for the investment decisions under climate policy uncertainties.CCS,IGCC and wind were the three technologies chosen to conduct the empirical analysis.The main findings shown that the optimal investment order for these three technologies is wind,IGCC and CCS.Moreover,the intensity of climate policy will affect the choices between CCS and IGCC.In addition,stricter climate policy in the early period will work better in motivating the investment of low-carbon technology.(4)Considering the power system resources from the generation side,transmission side and consumption side,an economic dispatching model for the low-carbon electricity systems' optimal operation was created,using the mixed integer linear programming method.This model could be served as scientific tools for the cost benefit analysis during the dispatching mechanism reform.China's power system operation in 2014 was selected to conduct the empirical analysis.The results shown that economic dispatch can achieve an energy saving benefits of 68.7 billion yuan in 2014,which consists of 63.81 Mt of coal conservation and 177 Mt of carbon emission reduction.Moreover,the challenges facing the economic dispatch implementation was analyzed basing on a political economy framework,several challenges were identified such as the benefits re-allocation among generators of different ownerships and local protectionism in the interregional electricity trading.At last,solutions were proposed for these summarized political and economic challenges.(5)Following the ideas of combining the economic theory and its application experience,this dissertation summarized the theoretical basis,international experience and current status of the market and regulation design for a low-carbon electricity system.Then,a methodology was proposed for market and regulation design for the electricity system's low-carbon transition.From the perspective of electricity market design,the demand side response and energy storage resources need more attention in the planning,external cost should be integrated into the electricity market,long-term supporting mechanism for the low-carbon technologies could be established.From the perspective of regulatory mechanism design,an independent regulatory agency for the electricity system need to be established,a close-loop regulatory mechanism of ‘Access-Investment-Service Quality–Price-Exit'is recommended for the power grid companies,and the implementation of renewables' dispatch priority must be supervised.