Abstract
Within the project ImmoGap, the so-called performance gap for multifamily buildings was analysed. It contributes to a better classification and a clearer definition of the term “performance gap”. As a first step, a literature study on this topic was carried out. In principle, the “Performance Gap” is understood as an additional consumption of energy or a failure to meet energy benchmarks. The term “Performance Gap” suggests that a desired service is not provided. This is critical, because there are several reasons why a building consumes more energy than originally planned. In the project, the heating energy consumption of 65 multifamily buildings was compared with the design heating demand according to the Swiss standard SIA 380/1 (based on EN ISO 13790:2008). In contrast to other studies, the project team was able to access measurement data with a very high time resolution. On average, the heat demand calculated with standard use is exceeded by 44%. Four of the buildings show an additional consumption between 100% and 115%. Detailed investigations with simulations and measurements show that the additional consumption can largely be explained by the user behaviour regarding shading, ventilation and room temperature, which deviate from the standard. If the observed user behaviour was already used in the demand calculation, the examined buildings on average would not show any “performance gap”.
Highlights
In Switzerland, around 1.6 million buildings account for about half of the country's primary energy demand [1]
The term performance gap is usually associated with increased energy consumption
One reason for this may be that the energy contractor is interested in operating his systems in the best possible way, e.g. the coefficient of performance (COP) of a heat pump decreases with higher heating flow temperature
Summary
In Switzerland, around 1.6 million buildings account for about half of the country's primary energy demand [1]. For this reason, the building sector plays an important role in energy research and, in particular, in increasing the efficiency. Various studies have shown that there is sometimes a clear difference between the energy consumption according to the design calculations and the real consumption of buildings measured during operation. This is referred to as the "performance gap". Individual findings from the measurement data evaluation were examined in more detail using dynamic annual building simulations
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have