Meta study on future cross-sectoral decarbonization target systems in comparison to current status of technologies: Discussion Paper

To reach the German targets to reduce CO2-emissions by 80 to 95% in relation to 1990 by 2050 an increase of installed capacity of renewable energy technologies, storages as well as technologies for power-to-X applications is well accepted in research in the field of energy system analysis. However current studies all result in different system compositions, which are due to many reasons. This meta-analysis assesses the bandwidth of technologies in the year 2050, needed for the above mentioned CO2-emission reduction, and compares the values to an extrapolation of current trend of the technologies. It is the goal to identify technology aspects, which need to be adapted to reach the goals as well as show trends in technologies, which are in line with the CO2-emission reduction targets. The results show, that higher emission reduction targets require an accelerated effort to decrease the primary energy demand. On technology side, wind energy, photovoltaics and biomass are mature technologies and show a tendency to reach the installed capacities to meet the emission reduction targets of 80%. Biomass energy and hydropower may not be expanded to a large extent, geothermal usage will either stay in a niche market or needs strong development. A strong increase of the heating technologies heat pumps and solar thermal until the year 2050 is unavoidable. Storages will be massively exploited, especially batteries in vehicles, stationary batteries and power-to-X storages, whereas pumped hydro storages exploitation is limited, due to available land and social acceptance

Stromerzeugung aus Windenergie

Im Gegensatz zu der direkten Sonnenenergie ist die Windenergie eine indirekte Art der Sonnenenergie. Die Einstrahlung der Sonne erwärmt die Erdoberfläche und die darüber liegenden Luftschichten unterschiedlich – d. h., wegen ihrer niedrigen Wärmekapazität werden im Sommerhalbjahr die Kontinentalflächen bei Tag stärker erwärmt als die Ozeane. Dies bewirkt auf verschiedenen Gebieten der Erdoberfläche Dichte- und Druckunterschiede, die in fluktuierenden Luftströmungen ihren Ausgleich finden. Diese fluktuierenden Luftströmungen bzw.Winde können technisch durchWindenergieanlagen (WEA) genutzt werden, die in den strömenden Luftmassen enthaltene kinetische Energie in elektrische Energie umwandeln. Dabei wird die Energie des Windes über die Rotorblätter zunächst in mechanische Rotationsenergie und dann über einen Generator in elektrische Energie umgewandelt (Abb. 7.1)