a–f, Onshore wind power (a–c) and solar PVs (d–f). a,d, National historical growth trajectories with the take-off years (achieving 1% penetration) aligned and indicative countries labelled. b,e, World wind (b) and solar (e) feasibility space. c,f, OECD wind (c) and solar (f) feasibility space. In the second (b,e) and third (c,f) columns, blue-shaded areas represent approximations of the historical data from the first column (a,d) with Gompertz models. The intensity of the shading reflects the number of modelled curves above a specific point and lighter colours correspond to fewer precedents. The second and third columns also show empirical observations (white dots) and Gompertz fits (representing the best fit, shown by blue lines) for the world and the OECD region, respectively, in cases where growth is stable (Table 2). Turquoise and purple error bars show the IQRs of wind and solar in the 1.5 and 2 °C pathways, respectively (the dots show the medians)45,46. All the values are normalized to the take-off year. See Supplementary Table 33 for country codes.