How to choose a suitable network tariff? - Evaluating network tariffs under increasing integration of distributed energy resources

Abstract

In a changing power system with increasing penetrations of distributed energy resources, traditional network tariffs might not be able to meet the underlying requirements. Therefore, it is necessary to assess suitable alternatives. We propose a new two-stage process and evaluation framework to support an informed decision process and test them in a Swiss environment. In the first stage, stakeholder interviews determine the relevant design criteria. In the second step, these are translated into a quantitative evaluation framework. The single indicators are weighted by expert weighting, following the analytic hierarchy process, to arrive at the final ranking. The application in a case study shows that the final ranking of the examined tariff structures depends on expert weighting. It is therefore vital to work on a shared understanding of the importance of the different criteria. Moreover, in a scenario with high shares of distributed energy resources, the volumetric tariff shows the lowest performance independent of expert weighting. This result stresses the importance of adapting network tariffs for a future power system with high penetrations of distributed energy sources. Our open-source evaluation tool can help with an informed and transparent decision process.