A global dataset of the cost of capital for renewable energy projects

The cost of capital (CoC) critically influences the levelized cost of renewable energy and, by extension, the global low-carbon transition. However, reliable and consistent CoC data remain scarce, limiting an appropriate reflection of CoC differences in energy system and integrated assessment models. We present a global dataset of CoC for renewable energy projects, covering 68 countries from 2010 to 2022 and focusing on three key technologies: utility-scale solar photovoltaics, onshore wind, and offshore wind. We systematically compile and standardize data from academic literature and international organizations, ensuring methodological comparability. Our dataset includes 1,429 data points, of which 366 provide nominal, after-tax weighted average cost of capital values. We conduct technical validation through cross-technology comparisons, temporal consistency checks, and source triangulation. By addressing a key data gap, this dataset aims to support evidence-based energy policy analysis and advance the understanding of how financing conditions impact renewable energy costs globally.