Vortrag im Rahmen der 11. Internationalen Energiewirtschaftstagung IEWT vom 13. - 15. Februar 2019 in Wien
Motivation and Research Question
For scenario generation the first step is to identify the model parameters and to quantify them in a second step. Therefore, a metastudy is realized to investigate what the main key factors are and to present them graphically. Furthermore, similarities and differences for the selected scenarios are analysed with respect to the identified key factor. The aim is to demonstrate which factors influence the future energy system the most, to identify game changers (key factors with which the target scenarios can reach their aim) and to set them realistic limitations (range in which the particular key factor can be chosen).
To analyse the key factors, a shell model is constructed. Starting from the centre, the energy system gets break down with every following shell. Depending on the assumed perspective, the scenarios are built either by going from outer to inner shell or vice versa. The quantitative scenario modeller starts from the centre, the qualitative storyteller from outside to create the story behind the scenario. For better understanding, the number of shells is restricted to four. In this work, the key factors were collected, hierarchically sorted and then embedded in the shell model.
In total seven representative studies with in total 17 scenarios (6 trend scenarios, 6 target scenarios with 80% emission reduction in respect to 1990 and 5 target scenarios with 95% emission reduction) were selected. The selection was based on the following criteria: actuality, that different models were used, a homogenous selection of trend and the different target scenarios and an extensive documentation. The selected studies are shown in Table 1.
Table 1: Selected studies
Results and Conclusions
To give guidance to both perspective for the scenario generation for the scenario generation, a shell model is constructed splitting up the energy system down to the context factors (see Figure 1).
Figure 1: Shell model for the (A) German / (B) European energy system, containing the four shells Power system (yellow), Energy End-use sectors (green), End-use sector - specific parameters (orange) and Context Shell (blue): the storyteller starts from the outside (see blue arrow) with the context factors going in, the modeller starts from the centre (yellow arrow) with the power system going out.
The second research question was how the key factors vary between the different scenarios. To answer this question, we present the key factors in boxplots (exemplary in Figure 2). Key factors as the renovation rate or the amount of electricity in the industry differ significantly, while in contrast the population development is very homogenous (since a stable Germany is assumed). The great range for e.g. the renovating rate reflects the uncertainty for the transformation path to 2050. For scenario generation the attention has to focus on these uncertain factors since they influence the future energy system the most. From the boxplots, also limitations/ranges for the key factors can be extracted.
Figure 2: Boxplots of some exemplary key factors for 2050
 Gerbert, Philipp, et al. "Klimapfade für Deutschland." The Boston Consulting Group und (2018).
 Prognos, E. W. I. "GWS (2014): Entwicklung der Energiemärkte–Energiereferenzprognose." Studie im Auftrag des Bundesministeriums für Wirtschaft und Technologie (heute: Bundesministerium für Wirtschaft und Energie), Basel, Köln, Osnabrück (2014).
 Repenning, J., et al. "Klimaschutzszenario 2050. Studie im Auftrag des Bundesministeriums für Umwelt, Naturschutz, Bau und Reaktorsicherheit (BMUB) No. 2. Endbericht. Berlin: Öko-Institut eV; Fraunhofer ISI." (2017).
 Capros, P., et al. "EU Reference Scenario 2016-Energy, transport and GHG emissions Trends to 2050." (2016).
 Fraunhofer, I. S. I. "Langfristszenarien für die Transformation des Energiesystems in Deutschland." Studie im Auftrag des Bundesministeriums für Wirtschaft und Energie (2017).
 dena-Leitstudie Integrierte Energiewende - Zwischenfazit Impulse und Erkenntnisse aus dem Studienprozess. Berlin: Deutsche Energie-Agentur GmbH (dena), 2017.
 Günther, Jens et al.: Den Weg zu einem treibhausgasneutralen Deutschland ressourcenschonend gestalten. Berlin: Umweltbundesamt, 2017.