Seasonal and annual variability of the global onshore and offshore wind power resource at 100 m

We present the results of numerical simulations of the global wind power potential over land and offshore with a coupled climate-meteorological-air pollution model, GATOR-GCMOM, that dynamically calculates wind power at the 100-m hub height of a modern 5 MW wind turbine at each time step. The model was run at various horizontal resolutions (4x5, 2x2.5, and 1.5x1.5 degrees of latitude and longitude) and with various initial conditions (summer or winter) for at least four years each. The global delivered wind power potential at 100 m at fast-wind locations (≥7 m/s) over land, excluding both polar regions, is found to be 138-150 TW (TW=1012 Watts) on average. This result further supports previous observation-based estimates of 72 TW at 80 m and model-based estimates of 79-126 TW at 100 m. Seasonal variations are however significant, with values as low as 94-102 TW in June-July-August (JJA) to 218-246 TW in December-January-February (DJF), with minima in September and maxima in January in all simulations. Global wind power over land at fast-wind locations during DJF is 1.6-2.5 times greater than that during JJA on average. Furthermore, the average wind power over land in the Northern Hemisphere (NH) is ∼126 TW, over 5 times greater than the Southern Hemisphere (SH) average (∼24 TW). In December, the NH wind power over land is up to 32 times greater than that in the SH. This suggests that the two hemispheres have different wind resources, driven by the different distributions of land and ocean areas. The offshore delivered wind power potential (excluding polar regions) is 15-23 TW at 100 m on average, consistent with previous estimates of 18-21 TW, varying between 16-17 and 19-31 TW from JJA to DJF. Wind power over land and near shore in fast-wind locations (which are 7-8% of the total land excluding polar regions) represents 7-10% of the theoretical global wind power over land plus ocean at all wind speeds of ∼1700 TW. Available wind power over land and near shore in fast-wind locations could theoretically satisfy the world power demand of 12.5 TW today 9-14 times over, even considering the slight reduction in wind speeds due to the extraction of energy from the atmosphere by wind turbines.