Energy policy measures and subsequent support schemes in Germany and Europe have triggered large-scale deployment of renewable energy sources for electricity. This rising share of renewables in the electricity supply leads to a series of technical and economic effects. The present work analyzes the economic impacts of renewable energy sources for electricity in Central Western Europe and especially in Germany. Challenges for the German electricity system lie in the usage of conventional generation capacity. With further deployment of renewable energy sources, the operation time of conventional power plants decreases and, as shown here, the generation pattern of former base-load technologies changes. Furthermore, as a consequence of falling wholesale prices partly due to the merit-order effect, conventional power plants suffer not only from reduced generation patterns, but also from impairments on their book values of respective utilities. A survey of annual reports reveals the relevant orders of magnitude. The macroeconomic impacts of the energy transition in Germany so far are strongly linked to the deployment of renewable energy sources of electricity since the year 2000, which was triggered by the Renewable Energy Sources Act. Using a Keynesian approach, this work shows that promoting renewable energy sources is linked with a phase of economic growth followed by a phase of relative economic recession. The merit-order effect of renewable energy sources, which describes falling wholesale prices for electricity with increasing penetration of renewable electricity generation, was proven and quantified empirically over a decade ago. While the European wholesale markets have grown further together, and the share of renewables in the electricity supply has risen, new questions arise, particularly the question of to what extent cross-border spillover effects of renewable generation of electricity play a role. The research question is analyzed using two different approaches: a simple fundamental model and a more advanced econometric time series approach. Elements of ARIMA models and principal components analysis are found to describe the system appropriately. The results delivered by both models are similar. It is shown that spillover effects of renewable generation exist in Central Western Europe, and the non-negligible order of magnitude is calculated. It is of particular importance when looking at the spillover effects coming from the German electricity system. They have the same order of magnitude as the corresponding domestic merit-order effects of cross-border countries. In particular, the spillover effect coming from German solar electricity generation is larger than that of wind turbines. Lastly, it can be shown that short-term forecasting of electricity prices with ARIMAX models can be improved in France by taking into account cross-border predictions of renewable electricity generation.