Research on wind speed change for wind power generation in Hokkaido and Tohoku region

  • Yasuhiko AZEGAMI, 2014: Research on wind speed change for wind power generation in Hokkaido and Tohoku region .

Abstract


This study evaluates on atmospheric and terrain factors of rapid change in wind speed in Hokkaido and Tohoku region, using AMeDAS data., additionally, characteristics of the rapid change in wind speed is individually investigated for each area. As a result of analysises, it was revealed that even though rapid change in wind speed is very local phenomenon and tends to occur frequently at the site with large wind speed, in southern part of Tohoku region, even at the with small wind speed, there are some sites where it occurs frequently. Also, the factors causing phenomenon of rapid change in wind speed within six hours include seasonal winds, approach and passage of low pressure, passage of cold front and inflow of upper-level wind accompanied with collapse of stable layer. In many cases of the phenomenon, there was low pressure around Hokkaido and Tohoku region. Investigating the positions of low pressure during rapid change in wind speed with AMeDAS, it was found that the positions of low pressure causing wind speed change are various at each point. Northwest part in Hokkaido, Tokachi plains and Ishikari plains are the areas where have a bias in the position of low pressure during rapid rise of wind speed. In northwest part in Hokkaido, rapid increase of wind speed was observed many times in the case of that low pressure is above the Sea of Japan. In Tokachi plains and Ishikari plains, the phenomenon was observed many times as well when low pressure is above the Sea of Japan. In Tokachi plains and Ishikari plains, the phenomenon was observed many times as well when low pressure is above the Sea of Okhotsk. As for reason of these effects, it is because wind speed rapidly increases when the direction of pressure gradient or inflow of upper-level wind and the direction of valley or mountain pass accord Therefore, it appears that the relation between synoptic place and landform is heavily involved in rapid increase of wind speed.

Keywords:Renewable energy, Wind power generation, Wind speed rapid change,Hokkaido, Tohoku region