Commission Decision (EU) 2017/1797 of 23 May 2017 on the aid schemes SA.42393 (2016/C) (ex 2015/N) implemented by Germany for certain end-consumers (reduced CHP surcharge) and SA.47887 (2017/N) which Germany is planning to implement in order to extend the CHP support scheme as regards CHP installations used in closed networks (notified under document C(2017) 3400) (Text with EEA relevance. )