Three professors from the Physikalisches Institut Universität Heidelberg have written a very short article in February 2015, titled “Findet eine Energiewende statt?” Contrary to what one usually reads (i.e. the Energiewende is only seen as implying electricity production), they discuss how the amount of fossil energies in the total German energy consumption has changed between 2000 and 2013. During that period, a solar photo-voltaic capacity of nearly 39 GW, and a wind-turbine capacity of approx. 34 GW were installed, quite impressive numbers (a large nuclear reactor has a 1.5 GW capacity)!
The costs of the PV installations alone installed from 2000 to 2012 are estimated at 108 billion Euro (including the yet to pay amounts for the future feed-in). The total costs of the EEG (Erneuerbare Energie Gesetz) are staggering, and mostly unknown. One estimation by Hermann (2011), actually seen as much too low, gives a total of 350 billion Euro up to 2030; 500 billion probably will be exceeded.
What is the effect of this huge effort? The figure below shows the total energy consumption in Germany from 2000 to 2013. The left scale shows the percentages, with the situation in 2000 taken as 100%. I added the boxes and arrows.
We see that the percentage of fossil fuel energy was about 84% in 2000 and remains at least 80% in 2013 compared to the 2000 reference; actually it is 90% of the slightly lower total consumption in 2013. So in 14 years of extraordinary expansion of renewables there is at best a minuscule diminution of the total amount of fossil fuels used for heating, driving, industrial processes and electricity production (and even an increase in the 2013 percentage).
The professors rightly conclude: “Der bisherige Ausbau der Wind- und Solarenergie ist augenfällig, das bisher Erreichte fällt aber sehr bescheiden aus, gemessen am Gesamtziel einer weitgehend von fossilen Energieträgern unabhängigen Energieversorgung unseres Landes”.