Simulating the effects of climate change and afforestation on wind power potential in Nigeria

The objective of this study is to determine the effects of global warming and future afforestation on wind power potential in Nigeria. A series of multi-year simulations of a regional climate model (ICTP-RegCM3) for 1981-2000 (baseline) and 2031-2050 (future with elevated CO2 under A1B emission scenario) periods, generated from a previous experimental study on the impacts of afforestation on the region's climate, were used. In the study, land-use patterns produced from seven different hypothetical afforestation scenarios were then used as boundary conditions in RegCM3 to simulate various future climate scenarios. Four of these options assumed random (i.e. 100, 75, 50 and 25%) afforestation over the country, while the other three assumed zonal (i.e. North (RNZ), Middle-belt (RMZ), and South (RSZ)) afforestation. Wind power density varied with season across the country. The north-eastern regions had the highest potential for wind power harvesting with the peaks (120 W/m2 at 10 m; 260 W/m2 at 100 m hub heights) during the dry season. A rise (+10 to +30%) in wind power over most parts of the country during the wet season (May to July) and a decrease (−10 to −25%) in dry season (October to January) were projected. Random afforestation generally suggested negative significant impacts (25-100%) on future wind power over the country. However, zonal afforestation had positive (≤ +20%) impacts upwind the afforested zone but negative (≈ −100%) over the afforested zone. Future RSZ afforestation option was found to enhance the wind power harvesting potential of the north-eastern regions of Nigeria.