Energy landscapes with less than two degrees of global warming – a comparative case study of two German regions

In order to achieve the Paris climate target of limiting global warming to below 2 °C compared to pre-industrial levels, the German government has launched the Climate Action Plan 2050. According to this plan, Germany is to achieve climate neutrality by 2045, which will require a comprehensive transformation of the energy sector, involving the gradual phasing-out of high-emission coal-fired power generation and the continuous expansion of renewable energies, especially wind and photovoltaic (PV). However, the low energy density of renewables leads to an immense demand for land. This results in major landscape changes, thereby triggering substantial land-use conflicts. Depending on the legal framework, the spatial patterns of these energy landscapes can vary considerably. The objective of our study is to analyze and visualize the potential spatio-temporal patterns of renewable energies for two regions that differ considerably from each other in terms of population size, economic structure, local industry, and natural potential for renewable energies. The first region under consideration is the rural Allgäu planning region, located in the far southwest of Bavaria, Southern Germany, the second is the governmental district of Cologne in Western Germany. The core of the study is the development of a dynamic distribution algorithm for the wind and PV locations for the modelling period 2023 – 2045. It facilitates the adjustment of assumed legal and consumption scenarios to estimate their respective impacts. The outputs of the algorithm are transferred to a geographic information system for visualization. Regional estimates of future electricity demand as well as wind and PV potentials serve as input data. The findings indicate that the objective of achieving climate neutrality in the Allgäu region by the year 2045 is, in principle, feasible across all scenarios examined. This assertion is accompanied by the recognition that achieving this objective will necessitate substantial alterations to the existing landscape, with some of these alterations being concentrated in specific areas. The magnitude of these anticipated changes varies significantly between the various scenarios considered in this study. The analysis indicates that the availability of sufficient PV potential is a prerequisite for the realization of climate neutrality in all scenarios, whilst the availability of wind potential is consistently found to be inadequate, with its capacity being exhausted well in advance of the conclusion of the modelling period. Conversely, the analysis indicates that attaining climate neutrality remains unfeasible in the Cologne region, even under scenarios of maximal renewable energy expansion, necessitating substantial alterations to the landscape. The study underscores the necessity for comprehensive assessments of regional factors to ascertain the viability of achieving climate neutrality.