Fig. 1: Temporal variability of solar and wind resources and electricity demand.

Climatological variability of the area-weighted median power from solar (orange) and wind (blue) resources for the selected country from six continents during the 39-year period 1980–2018. The countries (from the top row to the bottom row) are China (a, g, m), Germany (b, h, n), contiguous U.S. (c, i, o), South Africa (d, j, p), Brazil (e, k, q), and Australia (f, l, r). The left column (a–f) depicts the daily and seasonal variability, the middle column (g–l) depicts hourly summer (June, July, and August) variability, and the right column (m–r) depicts hourly winter (December, January, and February) variability. The lines represent the median, the dark shading represents the inner 50% of observations (25th to 75th percentile) and the light shading represents the outer 50% of observations (0th to 100th percentile) of the daily averaged value for that same day in each of the 39 years of record. Red curves in each panel represent electricity demand for a single, most recent, available year for each country. The time of day shown is the local time of each country and its relation to Coordinated Universal Time (UTC) is shown. Note that the middle of local time zones has been selected for the countries with multiple time zones. The solar, wind, and demand data are each normalized by dividing by their respective 39-year mean value.