Geophysical constraints on the reliability of solar and wind power worldwide

Nat Commun. 2021 Oct 22;12(1):6146. doi: 10.1038/s41467-021-26355-z.

Authors

Dan Tong^{1

2

3}, David J Farnham⁴, Lei Duan⁴, Qiang Zhang⁵, Nathan S Lewis^{4

6}, Ken Caldeira^{4

7}, Steven J Davis^{8

4

9}

Affiliations

¹ Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, 100084, China. dantong@tsinghua.edu.cn.
² Department of Earth System Science, University of California, Irvine, CA, 92697, USA. dantong@tsinghua.edu.cn.
³ Department of Global Ecology, Carnegie Institution for Science, Stanford, CA, 94035, USA. dantong@tsinghua.edu.cn.
⁴ Department of Global Ecology, Carnegie Institution for Science, Stanford, CA, 94035, USA.
⁵ Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, 100084, China.
⁶ Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
⁷ Breakthrough Energy, 4110 Carillon Pt., Kirkland, WA, 98033, USA.
⁸ Department of Earth System Science, University of California, Irvine, CA, 92697, USA.
⁹ Department of Civil and Environmental Engineering, University of California, Irvine, CA, 92697, USA.

Abstract

If future net-zero emissions energy systems rely heavily on solar and wind resources, spatial and temporal mismatches between resource availability and electricity demand may challenge system reliability. Using 39 years of hourly reanalysis data (1980-2018), we analyze the ability of solar and wind resources to meet electricity demand in 42 countries, varying the hypothetical scale and mix of renewable generation as well as energy storage capacity. Assuming perfect transmission and annual generation equal to annual demand, but no energy storage, we find the most reliable renewable electricity systems are wind-heavy and satisfy countries' electricity demand in 72-91% of hours (83-94% by adding 12 h of storage). Yet even in systems which meet >90% of demand, hundreds of hours of unmet demand may occur annually. Our analysis helps quantify the power, energy, and utilization rates of additional energy storage, demand management, or curtailment, as well as the benefits of regional aggregation.