In a power generation system with a low emissions coefficient and with efficient installations regarding consumption, co-generation lacks enough true meaning from the energy efficiency point of view, since it fails to provide savings in primary energy.
Co-generation may play a relevant role in the transition towards an Efficiency Scenario, within certain applications. But in the long term, co-generation (neither based on fossil fuels nor biomass) is not considered as one of the technologies involved in meeting the heating needs of buildings.
Something similar happens with solar thermal energy, which, in the transition to an Efficiency system, will continue to play an important role in the production of hot water in buildings, but it is not considered able to cover the entire heating demand due to the cost. Within the industrial sector, solar thermal energy is used for low, medium and high temperature applications.