Two of the most widely emphasized contenders for carbon emissions reduction in the electricity sector are nuclear power and renewable energy. While scenarios regularly question the potential impacts of adoption of various technology mixes in the future, it is less clear which technology has been associated with greater historical emission reductions. Here, we use multiple regression analyses on global datasets of national carbon emissions and renewable and nuclear electricity production across 123 countries over 25 years to examine systematically patterns in how countries variously using nuclear power and renewables contrastingly show higher or lower carbon emissions. We find that larger-scale national nuclear attachments do not tend to associate with significantly lower carbon emissions while renewables do. We also find a negative association between the scales of national nuclear and renewables attachments. This suggests nuclear and renewables attachments tend to crowd each other out.

电力部门减少碳排放的最受关注的竞争者中有两个是核能和可再生能源。尽管情景经常质疑未来采用各种技术组合的潜在影响，但不清楚哪种技术与更大的历史减排量相关。在这里，我们对25年中123个国家/地区的国家碳排放量以及可再生能源和核电生产的全球数据集进行了多元回归分析，系统地研究了各国不同地使用核能和可再生能源的方式如何显示出更高或更低的碳排放。我们发现，大规模的国家核附件不会趋向于显着降低碳排放量，而可再生能源却是如此。我们还发现国家核电和可再生能源附件的规模之间存在负相关关系。这表明核能和可再生能源的附件往往会相互挤出。