我国可再生能源发电占比逐年增加,由于风电和光伏等可再生能源发电具有波动性、间歇性和随机性的特点,为了提高可再生能源消纳能力,传统火电机组需要在深度调峰的同时具有较强的灵活性。本文提出了一种基于可再生能源制氢的调峰电厂掺氢燃烧系统构想,并以350MWe火电机组为例进行系统方案设计,研究了不同掺氢比例和调峰负荷下的技术经济性,分析了煤炭价格、碳税和制氢电价对调峰电厂度电成本的影响,讨论了不同参数影响下该项目的投资回收期。结果表明:以合适比例掺氢辅助燃烧后进一步深调锅炉负荷,具有较好的经济效益。若不计碳税和制氢用电成本,标准煤价以800元/t计算,不掺烧氢气时(方案1)的度电成本为0.347元/kWh,以20%掺氢比例辅助燃烧后进一步深调锅炉负荷至20%THA(方案5)可将度电成本控制在仅增加2.0%。当标准煤价大于1800元/t或碳税大于400元/tCO2时,火电机组掺氢所带来的省煤收益和降碳收益愈加显著,改造方案在度电成本上开始占据优势。但随着制氢电价的提高,掺氢改造方案的度电成本会随之增加。当标准煤价为1000元/t、碳税为100元/tCO2、不计制氢用电成本时,方案5的投资回收期最短,为10.65a。若未来煤炭价格和碳税价格进一步提高,火电机组掺氢改造的经济效益更加显著。

The proportion of renewable energy power generation in China has increased year by year. As renewable energy powergeneration,such as wind power and photovoltaic,is characterized by volatility,intermittency,and stochasticity,traditional thermal powerunits need to be highly flexible while deeply peaking to improve the capacity of renewable energy consumption. In this study,a hydrogenco-firing system for peaking power plants with hydrogen production from renewable energy is proposed. The schematic design of thesystem is carried out with a 350 MWe thermal power unit as an example,the technical economics of the system with different hydrogenblending ratios andpeaking loads are investigated. Then the impacts of the coal price,carbon tax,and hydrogen production tariffs on theelectricity cost per kWh of the peaking plant are analyzed,and the payback period of the project is discussed. The results show that furtherdeep adjustment of boiler load after hydrogen co-firing with an appropriate ratio has better economic benefits. If carbon tax and hydrogen production tariffs are not taken into account,and the coal price is calculated according to 800 yuan/t,the electricity cost without hydrogenco-firing (Scenario 1)is 0.347 yuan/kWh. Further deep adjustment of the boiler load to 20%THA after assisted comsbution with 20%hydrogen co-firing (Scenario 5) would control the electricity cost at an increase of 2.0%. When the coal price rises to over 1 800 yuan/tor the carbon tax rises to over 400 yuan/t CO2,the benefits of hydrogen co-firing in thermal power units in terms of coal saving and carbonreduction become increasingly significant,and the retrofitted scenarios start to dominate in terms of electricity cost per kWh. When thecoal price is 1 000 yuan/t and the carbon tax price is 100 yuan/t CO2 excluding the hydrogen production tariff,the payback period ofScenario 5 is the shortest,which is 10.65 years. If the coal price and carbon tax increase in the future,the economic benefit of hydrogen co-firing in thermal power units will be more significant.