The performance of a horizontal-axis cross-flow wind turbine and the flow field above a porous windbreak fence in oblique wind were investigated in a circuit-type wind tunnel with a semi-open test section by using scale models of the fence and the wind turbine. The inclined angle, θ, between the turbine and the flow direction was changed from 0? to 40?. The maximum power coefficient of a cross-flow wind turbine in the oblique wind was proportional to cos2θ. In order to suppress the decrement of power, the fixed end plates were installed at both ends of the cross-flow wind turbine. The power coefficient of the cross-flow wind turbine with the fixed end plates is higher than that without the fixed end plates at θ = 40?. The fixed end plates were effective in suppressing the decrement of power in oblique flow. Moreover, in order to obtain the same effect in the turbine located above a porous fence, the effect of deflector which was installed in front of a porous fence was also investigated. The maximum power coefficient of the cross-flow wind turbine located above a porous fence with deflectors at θ = 40? is higher than that without deflectors. In oblique flow, a cross-flow wind turbine located above a porous fence with deflectors is expected to produce more power than that of the porous fence without deflector.

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This paper shows a load assessment method for design of the 7MW offshore wind turbine on V-shaped semi-submersible floating structure, which will be installed off the coast of Fukushima prefecture in the Fukushima Floating Offshore Wind Farm Demonstration Project. We calculated the load of the floating offshore wind turbine by using the coupled model of a wind turbine and a floating structure, which was tuned based on the tank test results. In the load analysis, asymmetric floater response against directional wave was considered. Also stability of the floating offshore wind turbine related to blade pitch control induced vibration was evaluated. It was confirmed that induced vibration converged to small amplitude and did not have significant effect on fatigue and extreme loads.

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This document provides an opportunity to initiate a discussion about the possible introduction of zoning rules into Japan. For more than a decades specialists have agreed that both the Feed-in Tariff price system and zoning rules are essential for the development of the offshore wind industry as a national system in Japan. Since the FIT price system has already introduced in March 2014, we must initiate a discussion for ideal zoning rule for Japan based upon the experiences in Europe.

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