Minimizing visual impacts of renewable energy technologies and its implications for potential, costs, and energy transformation pathways: A nationwide study on Germany

The energy transition necessitates the massive deployment of large-scale wind turbines and solar photovoltaics (PV). However, numerous countries, including Germany, have experienced setbacks in the form of project cancellations and delays that impede the installation of these technologies, which are driven by various non-technical factors. Local opposition, prompted by concerns over the visual impact of renewable energy technologies on the surrounding landscape, is one of these. Past studies have sought to tackle this problem by incorporating the visibility of wind turbines into planning considerations and potential analyses. However, these analyses have been limited to small regions and do not account for the visibility of other renewable technologies, such as solar PV. This study employs a nationwide, integrated, reverse-viewshed analysis, potential analysis, and techno-economic analysis. Furthermore, we evaluate the effects of designing renewable energy systems that are not visible in scenic or densely-populated areas on the remaining energy potential, energy system costs, and technological choices necessary to achieving net zero emissions by 2045. Installations visible from areas with different scenicness ratings (1–9) and population density thresholds are used to define scenarios to account for the sensitivity of visual impacts on different degrees of landscape scenicness and viewed by different population segments. Our research reveals that wind turbines with the highest levelized cost of electricity (LCOE) in Germany coincide with those that are visible from the most scenic landscapes (scenicness level 9). Therefore, minimizing the visual impact of wind turbines by placing them out of sight from the most scenic landscape areas could align with cost-effectiveness objectives. However, if the visibility restrictions become too strict (e.g., that they not be visible from scenicness levels ≥ 5 or population densities ≥ 300 people/km2), there will not be enough wind power potential (e.g., the remaining 6.8 TWh/year or 2.4 TWh/year) to cost-effectively achieve German climate targets. Instead, PV systems, with a lower visual impact, would be more favorable and selected in the optimization to meet energy demands.