塔式太阳能辅助燃煤发电系统技术经济性分析

Techno-economic analysis of solar tower aided coal-fired power generation system

塔式太阳能辅助燃煤发电是一种提高太阳能利用率、降低燃煤消耗的发电技术。该技术是将高温塔式太阳能热与常规燃煤发电机组相耦合,利用塔式太阳集热场产生高温蒸汽并参与燃煤电站系统作功。本文对某1 000 MW塔式太阳能辅助燃煤发电系统在太阳辐射资源和电网电力调度波动下的发电量及其构成(燃煤发电和太阳能发电)和电站全生命周期内的技术经济性进行了研究。结果表明:塔式太阳能辅助燃煤发电系统运营期内平均光电转换效率为18.2%,远高于常规塔式太阳能热发电站的光电转换效率;电站项目的平准化电力成本为0.319元/(k W·h),所得税后财务内部收益率为11.29%,具有良好的收益能力和较低的投资成本;塔式太阳能辅助燃煤发电系统比相同电力调度下1 000 MW燃煤电站少燃煤257.4万t,减少CO2排放723.8万t;当考虑碳捕集成本时,为使该塔式太阳能辅助燃煤发电系统与相同容量燃煤电站具有相同的市场竞争力,则需国家电价补贴0.065元/(k W·h)。

Solar tower aided coal-fired power generation is a kind of technology which can improve the utilization of solar thermal energy and reduce coal consumption. In this technology, solar tower thermal energy with high temperature is coupled with the conventional coal-fired power generation systems. And the solar tower field generated high temperature steam to work in the coal-fired power plants. In this paper, the electricity generation and the composition thereof（generated from coal and solar energy） as well as techno-economic analysis during the whole lifecycle of an 1 000 MW solar tower aided coal-fired power generation system（STCG） are studied under variable direct normal irradiance（DNI） and grid power dispatching. The results show that the average solar-toelectricity efficiency of STCG is 18.2%, which is higher than common solar tower power plants. Levelized costs of electricity（LCOE） of STCG plant project is 0.319 yuan/（k W·h）, and internal rate of return is 11.29%, which show a good profitability and a low investment cost. In addition, STCG can save 2.574 million tons of coal and reduce 7.238 million tons of CO2 emission compared with coal-fired power plant with the same power dispatching. When considering the costs of CO2 capture, the feed-in tariff subsidy should be 0.065 yuan/（k W·h） for STCG to have the same market competitiveness with the same capacity coal-fired power plants.