Study: Spandau Old Town has potential for solar power28. October 2020
Oliver Arnhold and team win DIN Innovation Award5. November 2020
Abstract — Energy self-sufficiency is a central issue in the transformation process towards a 100% renewable energy supply, both at regional and neighbourhood level. Regarding the regional context, the main aim is to achieve full balance-sheet self-sufficiency, whereas the neighbourhood level strives for real partial energy self-sufficiency. The expansion of storage systems is not necessary for the balance sheet concepts at the regional level. At the neighbourhood level, on the other hand, semiautonomous concepts with electricity storage facilities are widespread. Based on the regional efforts towards self-sufficiency, the real implementation possibilities at neighbourhood level and the necessity of storage facilities in the overall system, this dissertation explores the influence of the size of semi-autonomous systems at regional and district level on the storage requirements and the resulting system costs. This thus answers the question to what extent energy regions and energetic neighbourhoods can meaningfully implement their self-sufficient supply targets taking storage facilities into account. In order to address these issues, energy system analyses were carried out on the basis of linear optimisation for a range of system sizes from a regional and district perspective and evaluated from a technical-economic point of view. The basis for the investigation is the model region „Osnabrück- Steinfurt“ served as a test-bed model region for the following analyses. At neighbourhood level, fictitious and real associations of household, commercial, and agricultural buildings with different photovoltaic expansion scenarios were mapped. In addition to the systemic optimum, the storage requirements resulting from an economic profitability were investigated. At the regional level, the results show that the size of the semi-autonomous system has a strong influence on storage requirements and system costs. The supply of regions on the district level can be mapped under certain conditions within the range of 80 to 90% self-sufficiency. At the municipal level, a self-sufficient consideration of the power supply is not meaningful due to the strong heterogeneity of the municipalities in production and consumption. The investigations at the neighbourhood level show clear synergies in the networking of individual households and the use of a shared neighbourhood storage facility. Compared to the regional level, the implementation of storage facilities at the neighbourhood level leads to significantly higher specific storage capacities and system costs in order to achieve comparable degrees of self-sufficiency. From the point of view of the actors, however, their investment is worthwhile and leads to similarly high degrees of selfsufficiency comparable to the regional level.