How wind power landscapes change: an attempt to quantify visual impact on land use and residents in Northern Jutland, Denmark

Following 25 years of continuous development, Danish wind energy landscapes are going to face changes. Ceased on-shore construction, unresolved re-powering and stalled regional planning characterize the situation overshadowed by off-shore development. One of the factors inhibiting development appears to be planning uncertainty regarding the future impact on landscapes. Visual impact has seldom been an issue so far, but growing turbine size and less local involvement may change this. This paper presents a deterministic approach of quantifying percieved visual impact on landscapes and population, taking into account that there is no clear threshold for perceived visual impact. A raster-based geographical information system (GIS) has been used to build a regional landscape model for Northern Jutland County, which is used to assess visibility of turbines in the period of 1990 to 2010. Multiple viewsheds are computed for a variety of thresholds of visual impact, and since overlaid with population and land use data. The results indicate that the construction of new turbines replacing 40% of the old turbine stock and raising the installed capacity by 20% will not add to the comparative impact in general. However, the pattern of visibility will become askew, and the present homogenous distribution of visibility will disappear. This skewness, together with changing ownership and receding local involvement, could eventually lead to lower popular acceptance of wind power.