火电与周边风/光电场集成的混合电站经济性分析

Economic Analysis of Coal-fired Power Plant Integrated With Wind/PV Fields

以热储能作为枢纽,利用已有燃煤电厂与国家输电网络,和光伏、风电集成多能互补电站,可提升新能源消纳比例与电网调峰能力。本文提出基于气氛保护的二元太阳盐与Hitec盐联合的四罐级联式方案并分析了技术经济性,结果显示四罐级联式的单位能量成本是传统双罐二元太阳盐储热的49%,充电价3 cents/kWh时,其度电成本也比二元太阳盐双罐式低约2.2 cents/kWh。由于利用燃煤电厂现有基础设施的初始投资减少,相较抽蓄、压缩空气、钒液流电池电站,储热型火电厂的度电成本在放电时间在9 h以内具有明显的优势。论文还调研了中国各省风、光、火电厂分布情况,内蒙、甘肃酒泉、山东都适合本方案的推行,以内蒙为例,其境内鄂尔多斯市、乌兰察布市尤为适合本方案的实施。

Integrating the existing coal-fired,solar,wind power plants,and high-temperature thermal energy storage can simultaneously increase the portion of renewables and enhance the flexibility of electricity supply in a power grid.In this paper,a four-tank cascade heat storage scheme based on the combination of solar salt and Hitec salt is proposed under protective gas,a techno-economical analysis is performed.The results show that the unit energy cost of the proposed cascade heat storage with four tanks accounts 49% of that of traditional two-tank solar salt storage system.At a charging price of 3 cents/kWh,the levelized cost of electricity of the four-tank cascade heat storage scheme is about 2.2 cents/kWh less than the traditional two tanks of solar salt scheme.The levelized cost of electricity of the proposed cascaded system is significantly lower than systems integrated with other energy storage technologies with discharging duration is less than 9 hours,due to the reduction in initial investment utilizing existing infrastructures of coal-fired power plants.After investigating the distribution of wind,photovoltaic,and coal-fired power plants in China,Inner Mongolia,Gansu,and Shandong provinces are suitable to push the integrated systems.Taking Inner Mongolia as am example,Ordos and Ulanqab cities are particularly fit for the scheme implementation.