Generation Expansion Planning Based On The Coordination Of Capacity Price And Wind,Solar And Fire Ratio

With the goal of "carbon peaking and carbon neutral",large-scale new energy sources on the grid have become an inevitable trend.To cope with the randomness and volatility of new energy sources and to ensure the safe and stable operation of the power system,thermal power units will gradually transform from generating power to regulating power.However,the electric energy market cannot reflect the capacity value of thermal power units as regulating power,which has led to large losses for thermal power enterprises and a lack of investment incentives for power generation enterprises,which will further affect the adequacy of power generation capacity of the power system and thus the reliability of the power system in the future.There is an urgent need to establish a reasonable capacity compensation mechanism to protect the returns of thermal power units and provide a positive investment signal for power producers.Therefore,this paper proposes a capacity compensation mechanism for thermal power plants that adapts to the current situation of China’s development and establishes a power supply planning model in which capacity tariffs are coordinated with power supplies,to explore the relationship between the price and power supply structure of capacity compensation tariff implementation,and to provide a reference for future capacity tariff implementation.The main innovations are as follow:Firstly,by analyzing the pricing method of the electricity spot market and the resulting lack of revenue for the units,the necessity of building a capacity compensation mechanism is clarified;three typical international capacity compensation mechanisms such as the capacity market mechanism,scarcity pricing mechanism and capacity subsidy mechanism are elaborated,and the specific practices of these mechanisms in foreign countries are introduced;on this basis,the applicability of each capacity compensation mechanism is analyzed in the light of the actual situation of China’s market construction,and a theoretical basis is laid for the design of the capacity compensation mechanism.Secondly,with reference to typical overseas capacity subsidy mechanisms,a thermal power capacity compensation mechanism based on the effective capacity of the unit is proposed for application in China,in which the compensation capacity is the effective capacity of the unit corrected for unit availability and years of operation,and the unit capacity tariff is determined in coordination with power supply planning and is capped according to the unit fixed cost accounting.This capacity compensation mechanism can provide capacity revenue for thermal power units while ensuring the reasonableness of the capacity tariff.Then,based on the thermal capacity compensation mechanism proposed in this paper,a bi-level generation expansion planning model is established to coordinate the capacity price and the ratio of wind,solar,and fire.The upper level aims to minimize the total annual cost of planning and optimize the power installation scheme and capacity price by considering the constraints of annual unit profit and capacity price.The lower level aims to minimize the typical daily operating cost and optimize the output of typical daily units.Finally,the constructed model is solved and the impact of carbon tax price and green certificate trading price on power supply planning results and capacity tariff is explored.The case studies show that the bi-level generation expansion planning model can ensure a minimum profit for the units,achieve coordinated planning of capacity tariff and power supply,provide positive investment signals for enterprises,and provide a reference basis for future capacity tariff formulation for the power system.