考虑氢能调峰要素的岛屿能源系统结构优化

Optimized island energy system with hydrogen peak-shaving

由于能源系统相对孤立,沿海岛屿的能源供应主要依靠大陆进口,有必要对岛屿能源系统进行优化,以充分利用清洁能源,减少能源进口需求。为此,以浙江省舟山群岛为例,基于碳夹点分析方法,优化岛屿能源系统中可再生绿色能源的比例,在满足能源需求的同时实现减排目标;考虑到岛屿的季节性能源波动会导致某个季节出现能源短缺或过剩的现象,引入氢能进行调峰,并对比了采用水力发电、风力发电、太阳能发电替代部分火力发电的3种减排方案的发电量及碳排放量。研究结果表明:(1)为完成舟山市电力减排目标(相对2021年减排CO_(2)14.5%),方案一需要1100.60 GW·h水力发电来代替火力发电,方案二需要1285.13 GW·h风力发电,方案三需要1164.79 GW·h太阳能发电;(2)在电能需求量较小的第一、二季度通过煤化工制氢28.17 kt,选择地下压缩方式储存并在电能需求量较大的第三、四季度进行利用,氢气的制取和储存成本共需5.82亿元,不仅可以解决用电高峰季节的能源短缺、用电低谷期的能源浪费,同时能完成全年减排14.5%的目标。结论认为,尽管方案三(太阳能发电)为经济性最优方案,全年共花费61.2亿元,但优势不明显,相比其他方案仅低0.3%左右;在条件允许的情况下应优先发展太阳能发电,在条件受限时风力和水力发电也同样具有优势。

Offshore islands,which are relatively isolated,are dependent upon the energy supply from the mainland.It is necessary to optimize the island energy system for clean energy utilization and reduced energy import.Taking the Zhoushan Archipelago in Zhejiang Province as an example,based on carbon emissions pinch analysis,the proportion of renewable energy in the island energy system was optimized to meet the energy demand while achieving emission reduction goals.Considering the seasonal energy fluctuations on the island,which may induce energy shortage or surplus,hydrogen energy was introduced for peak shaving,and the three schemes(hydropower,wind power and solar power)to replace part of coal-fired power was compared for their respective power generation and carbon emissions.The results show that to achieve emission reduction goal in power generation in Zhoushan City set in the 14th Five-Year Plan of Zhejiang Province(relative to the reduction of CO_(2) by 14.5% in 2021),1100.60 GWh of electricity from hydropower generation is needed for scheme 1285.13 GWh of electricity from wind power generation for scheme 2,and 1164.79 GWh of electricity from solar power generation for scheme 3.With the total cost of RMB582 million,28.17 kt of hydrogen is produced through coal chemical methods in the first and second quarters with low electricity demand,and stored by underground compression for utilization in the third and fourth quarters with high electricity demand,achieving peak shaving and valley filling as well as emissions reduction by 14.5%in the year.In conclusion,although solar power generation is the most cost-effective scheme,with a total cost of RMB6.12 billion throughout the year,it is just about 0.3%lower than the other two schemes;hence,priority should be given to the solar power generation when conditions permit,and wind power or hydropower generation when conditions are limited.