Comparison of dynamic simulations and the ISO 52016 standard for the assessment of building energy performance

In 2017, the ISO 52016-1:2017 standard introduced a new methodology for the assessment of the building energy performance as a replacement for the simplified method used in the ISO 13790:2008 standard. The capabilities of the new standard have been considerably improved with respect to those of the old standard, but currently there is a lack of analyses that assess the accuracy and limitations of the new standard applied to realistic multi-zone buildings of various types and in various climates. This paper presents a comprehensive analysis of the model accuracy for a wide range of building uses, envelope properties, climates, and heating/cooling needs, ranging from 5 kWh/m(2) to 216 kWh/m(2) for heating and from 23 kWh/m(2) to 170 kWh/m(2) for cooling. The analysis was done by comparing the results from the ISO 52016-1:2017 standard with the dynamic simulation model in TRNSYS. The differences between the two methods in the annual energy needs are up to 40% for heating and up to 18% for cooling. Furthermore, it is shown that the use of constant values of solar energy transmittance and the overall heat transfer coefficient for windows can cause substantial errors in the calculation of building energy needs, more so for buildings with high-performance windows. Although a certain level of discrepancy between the ISO 52016-1:2017 standard and TRNSYS also occurs in the calculation of heat transfer through opaque elements, the differences seem to be less pronounced than for windows.