Key issues to define a method of lightning risk assessment for wind farms

This paper describes a methodology and key issues of lightning risk assessment for wind farms. Methodology is based on IEC standard for wind turbines. Key issues comprise: influence of local terrain, the particularity of having multiple tall structures in a limited area, the influence of winter lightning activity, the percentage of upward lightning to wind turbines, aspects to consider concerning lightning data, seasonal variation of lightning and the need of methodology validation.