Sensitivity Analysis of the Thermal Energy Need of a Residential Building Assessed by means of the EN ISO 52016 Simplified Dynamic Method

Abstract

The EN ISO 52016-1:2018 technical standard has introduced a new simplified dynamic method for the calculation of the building energy need for heating and cooling. This new procedure combines a low amount of input data required, as for the previous quasi-steady and dynamic simplified methods of the withdrawn EN ISO 13790 standard, with an increased accuracy, which would reduce the gap with detailed dynamic methods. This work is part of a broader research activity aimed at investigating the new simplified dynamic model and highlighting its strengths and weaknesses, in terms of accuracy and robustness. Specifically, the work addresses the parameters that have a great influence on the final results and the effects of uncertainties in input data. To this purpose both standard and tailored energy performance assessments have been applied, in particular in the first one a continuous operation period of the space heating system was supposed, and in the second one an intermittent operation system was chosen. A sensitivity analysis was also carried out to quantify the variation of the heating and cooling loads with the set-point temperature, the windows physical properties, the heat capacity and the thermal transmission properties of opaque components, as well as the occupancy related input parameters, such as the internal heat gains and the ventilation flow rate. The analysis was applied to a multi-unit residential building located in Rome and built in the first half of the 20th century. The results outline absolute relevance of the set point temperatures. The significance of occupant behaviour and the importance of the correct definition of the component thermal properties is also pointed out through the comparison between the standard and tailored assessments.

Effects on Energy Demand in an Office Building Considering Location, Orientation, Façade Design and Internal Heat Gains—A Parametric Study

“…Internal heat gains: Occupancy behavior and consequently internal heat gains are among the hardest thing to predict for a new building, but as can be seen in the results of this study, among others [12,14,25], it has a huge effect on the total energy use. Different internal heat gains also affect the energy use differently depending on the location of the building.…”

“…They also state that, for low-energy offices, it is crucial to decrease user related electricity and internal heat gains. The above mentioned References [12][13][14][15][16] confirm that building energy simulation is an appropriate tool to analyze the thermal performance of buildings. In this paper, a parametric study was used to investigate the effects of the above-mentioned parameters: location, orientation, amount of internal heat gains, solar shading and façade design of an office buildings heating and cooling demand.…”

“…They concluded that a high level of thermal comfort is achievable by using very minor amounts of energy for heating and cooling in a Mediterranean climate by means of decent insulation, double glazed windows, variable shading devices and passive cooling by nighttime ventilation. A sensitivity analysis was conducted in Reference [14] to analyze the influence of solar transmittance of windows, indoor operative temperature set-points, model of mass distribution in building components and occupancy density of the heating and cooling demands and loads of a building. The authors conclude that operative temperature set-point is the main influencing parameter, and that occupancy density also has a large influence, especially during the cooling period.…”

Evaluation of Residential Buildings Savings for Various Envelope Retrofits and Heating Energy Sources: A Simulation Study

“…This is due to the fact that solar and internal thermal gains have a larger share in well-insulated buildings [16,17]. Additionally, the use of renewable sources also has an increasing impact on the hourly time step calculation method of heating and cooling energy needs [18,19]. According to EN ISO 52016-1 [20], it is therefore possible to evaluate the buildings under the dynamic method with an hourly time step.…”