不同装机容量下S-CO2塔式太阳能热发电系统的热力及经济性能分析

建立超临界CO₂布雷顿循环塔式太阳能热发电系统的热力性能和经济性能模型,比较不同装机容量下系统的年均效率,分析系统中各项成本占比及其随容量增长的变化规律,提出进一步降低发电成本的方法。结果表明,主要受镜场效率的影响,系统年均效率随装机容量增加先升后降,峰值为20 MW时的17.4%。发电成本随装机容量的增加而减小,由1 MW时的0.477 美元/kWh降至100 MW时的0.125 美元/kWh。减小镜场和储热的投资成本是降低大规模电站发电成本的关键。

THERMODYNAMIC AND ECONOMIC ANALYSIS OF SOLAR POWER TOWER SYSTEM BASED ON S-CO2 CYCLE WITH DIFFERENT INSTALLED CAPACITY

The thermodynamic and economic performance models of solar power tower system based on supercritical CO₂ Brayton cycle are established. The average annual efficiencies of the systems under different installed capacity are compared. The cost proportion of each item and its variation with the increase of installed capacity are analyzed. The methods to further reduce the cost of power generation are proposed. The results show that the average annual efficiency of the system first increases and then decreases with the increase of installed capacity, and its peak value is 17.4% at 20 MW, which is mainly affected by the solar field efficiency. The levelized cost of energy decreases with the increase of installed capacity, from 0.477 $/kWh at 1 MW to 0.125 $/kWh at 100 MW. Reducing the investment costs of solar field and thermal energy storage are the keys to reduce the power generation cost of large-scale power plant.