Two years earlier, the city of Bonn already purchased green electricity bearing the Grüner Strom-Label for the Stadthaus, the Altes Rathaus and the Stadtentwässerung. However, due to a council resolution on the "Masterplan Energiewende und Klimaschutz Bonn" (Bonn Energy Transition and Climate Protection Master Plan), the municipality went one step further: Since 2014, all municipal properties have been supplied by Stadtwerke Bonn with certified BonnNature Electricity  supplied.

For the total consumption, the municipal building management calculates with approx. 72,800 MWh per year. In comparison, the city of Bonn will save around 900,000 euros per year for the years 2017/18, as the contract was concluded at a favorable time.