[M-ZZ43] Renewable energy and earth science

[MZZ43-P04] Future changes in wind power generation seen in high-resolution regional climate projection data

*Masamichi Ohba¹ (1.Central Research Institute of Electric Power Industry)

Keywords:Wind energy, Climate change, Self-organizing maps

Since wind power generation is weather-dependent, it has been indicated that it can be affected by climate change. In this study, we investigated the impact of climate change on wind power generation in Japan in the future using high-resolution ensemble climate projection data downscaled to 5 km with attribution analysis using machine learning. Wind power generation was estimated from surface wind speeds and compared to the present climate at a 4-K temperature warming, showing a 3-15% decrease in annual accumulated generation from Honshu to the southern offshore region. The rate of future climate change varied with the seasons, with a decreasing trend from summer to autumn over most of Japan, and an increasing trend from winter to spring over the onshore plains of northern Japan. Clustering of weather patterns by self-organizing maps was conducted to separate the factors of future change into the impacts of dynamics (changes in pattern frequency) and thermodynamics (changes in intra-pattern wind speed) on climate change. The results suggest that the large scale decrease in wind resources in winter is mainly due to dynamical effects, while the increase in the onshore plains of northern Japan is due to thermodynamic effects, the former being related to changes in the direction of winter monsoon airflow, and the latter to a decrease in snow cover (increase in vertical momentum entrainment) associated with temperatures warming. The latter is related to the decrease in snow cover (increase in vertical momentum entrainment) associated with higher temperatures.