Decarbonisation options in the building sector

GHG savings through modernisation

The calculations for the 16 example buildings show that both the sector target for 2030 and the target for 2050 can be achieved, assuming that appropriate energy modernisation measures are carried out on the building envelope and energy-supply systems. The 2030 target can be achieved by a complete refurbishment of a (comparatively small) part of the existing buildings, or by a partial modernisation of a higher proportion of the building stock.

In many cases, especially in residential buildings, partial modernisation with gas condensing boilers and solar domestic hot water heating as well as energy-efficient upgrading of individual components of the building envelope would be sufficient to meet the 2030 target. This means that, at least the 2030 target can be achieved without giving preference to certain technologies. However, in order to be "2050-ready", the partial modernisation measures must avoid further modernisations of the same building component until 2050 and thus to additional costs. The modernisation of the energy supply system should be linked to a reduction of heat demand by improving the thermal insulation of buildings and using future-proof technologies.

The modernisation options considered in this study achieve very high GHG savings, especially in a complete renovation  reaching usually 70 % and more compared to the respective initial state. The exact order of magnitude depends not only on the structural changes but also on the chosen energy source. Further emission reductions require the use of emission-free or at least largely de-carbonised energy sources.

To the study "Analysis of specific decarbonisation options to achieve the energy and climate tar-gets 2030 and 2050 for different residential and non-residential building typologies" (website BMWi)

Authors Prognos: Nils Thamling, Dominik Rau, Sven Kreidelmeyer, Malek Sahnoun and partners from FIW Munich, ITG Institute and dena