Systematic investigation of building energy efficiency standard and hot water preparation systems’ influence on the heat load profile of districts

Abstract

Heat load profiles of new residential developments in rural, sub-urban, and urban context were generated by means of a generic model and dynamic simulations. The combined effect of district building density, building energy efficiency standard, and hot water preparation system on the heat load is discussed in detail. Hundred residential districts representing medium sized developments were defined by varying the distribution of building types. Therefore, a simplified building typology of 13 fictitious buildings was developed. The presented methodology allows to quickly estimate the total heat demand of new residential developments based on the plot ratio and buildings’ energy efficiency standard only.The investigations reveal that the building density as well as the hot water preparation system have a significant impact on the yearly district heating return temperatures. Instantaneous domestic hot water preparation results in up to 14 K lower annual average district heating return temperatures. However, the building density also has a significant influence on the return temperature, resulting in important differences between urban and rural districts.