The annual target of the German Federal Government for PV capacity increase of 2.5 GW was exceeded in 2020, but the goals of the energy transformation are still far away. On May 12, 2021, the German government approved climate targets that call for a balanced national greenhouse gas footprint by 2045 at the latest.
In order to cover all of our energy needs from renewable energies (RE), a massive expansion of the installed PV power is necessary, along with a number of other measures. More recent model-based scenarios calculate a reduction of energy-related greenhouse gas emissions alone of at least 90% in relation to 1990, with a PV expansion corridor of
130-650 GWp nominal capacity ([Prog], [BCG], [ESYS], [ISE11], [UBA8], [IRENA], [ISE12]). The scenarios make different assumptions about boundary conditions, e.g. for energy imports and questions of acceptance. Based on the scenarios "reference" and "inacceptance" [ISE12], a magnitude of 500 GWp installed PV capacity seems to be plausible.
If we calculate a PV expansion to 500 GWp by 2045, an average of 18 GWp of PV will have to be added annually. Increasingly, old systems must also be replaced. These replacement installations are currently still of little importance, but they will increase to around 17 GWp per year when fully expanded, assuming a lifetime of 30 years.
The German Renewable Energy Sources Act [EEG2021] defines an interim target for 2030 of a share of renewable energies (RE) of 65 percent of gross electricity consumption. This requires an average annual PV addition of at least 5-10 GWp, depending on the development of electricity demand and the expansion of wind power ([AGORA1], [BEE]). The German Renewable Energy Sources Act EEG, on the other hand, sets the PV expansion target at 100 GWp, corresponding to an average addition of just under 5 GWp per year.
From 2013-2018, power plants with a nominal output of only 1.9 GWp/a were installed on average in Germany [BMWi1], in 2020 the figure was 4.9 GWp [ISE4].
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