|| Rising prices for finite fossil energy carriers as well as increasing commitments on national and international level to address climate change are only some of the major drivers for a more sustainable use of energy. Energy contracting models – offered by energy service companies (ESCOs) – are common tools to enhance the sustainable use of energy through energy efficiency measures (EEM) and the system integration of renewable energy sources (RES). ESCOs can significantly help overcome financial constraints to investments in these fields. Their investments are amortised during the lifetime of a contracting agreement through the energy (cost) savings achieved on the customer side. Thus, ESCOs can provide a mean to reduce energy demand and CO2 emissions.