在竞争的发电市场中 ,用于支付发电机组成本和向用户收取电费的电力批发边际价格必须考虑到供电量的保证 ,又要考虑到长期和短期安全供电保证 ,即要考虑到电量和容量的双重保证。笔者从发电部门的角度 ,推出了就发电方而言的电力批发边际价格的最优表达式 ;最后分析了成本与边际价格不相等的原因 In competing power generation markets, the marginal wholesale price of electricity used to pay for generating unit costs and to charge consumers for electricity needs to take into account the guaranteed amount of electricity, as well as the long-term and short-term safeguards, taking into account both electricity and capacity Double guarantee. From the perspective of the power generation sector, the author introduces the optimal expression for the marginal price of power wholesale in terms of generating units. Finally, it analyzes the reasons why the cost is not equal to the marginal price