User behaviour impact on energy savings potential

When buildings are to undergo energy upgrading in Denmark, the national compliance checker, Be10, is often used to calculate expected energy savings for different energy-saving measures. The Be10 calculation is, however, very dependent on a variety of standard assumptions concerning the building and the residents' behaviour and if these defaults do not reflect actual circumstances, it can result in non-realisation of expected energy savings. Furthermore, a risk also exists that residents' behaviour change after the energy upgrading, e.g. to obtain improved comfort than what was possible before the upgrading and this could lead to further discrepancies between the calculated and the actual energy savings. This paper presents an analysis on how residents’ behaviour and the use of standard assumptions may influence expected energy savings. The analysis is performed on two typical single-family houses corresponding to different levels of energy consumption. The purpose of the analysis is to identify the importance of each of the four primary user-related parameters in terms of their relative and combined impact on the overall energy needs before/after upgrading; 1) Indoor temperature, 2) Internal heat gain, 3) Domestic hot water consumption and 4) Air change rate. Based on the analysis, a methodology is established that can be used to make more realistic and accurate predictions of expected energy savings associated with energy upgrading taking into account user behaviour.