Research Project: User behaviour and its influence on the energy consumption

Project briefing

• Status Completed
• Project duration December 2016 – July 2018
• Programme Future Building

This research project collects present knowledge about the energy consumption of residential buildings, about the effects of energy upgrades and about the influence of users. From this suggestions for supplementing the energy performance certificate are derived, aiming at a realistic assessment of energy savings by refurbishment measures and at an indication of the positive effects on the thermal comfort.

Project duration: December 2016 – July 2018

Background

The minimisation of the carbon dioxide emissions in the building sector is an important goal of the Federal Government of Germany. To achieve this, a comprehensive transformation of the German building stock will be necessary in the next few decades. Already now, many housing companies and private house owners are investing considerable funds in energy saving measures. Not only climate protection is an important motivation for refurbishments, but also the improvement of the thermal comfort of their buildings and the minimisation of energy costs. However, in view of the danger of a climate shift, efforts need to be stepped up significantly.

Nonetheless, currently there is some uncertainty among building owners, designers and energy consultants as to whether the consumption targets are actually achieved by refurbishments in practice. Also, it is not even clear how the actual "consumption target" is defined. The energy performance certificate based on calculated rating does not provide any meaningful information in this regard, as it is designed to proof compliance with energy requirements and not to estimate the energy consumption. On the other hand, in addition to the energy savings further positive effects of energy refurbishments are known, which are not yet highlighted in the energy performance certificate.

Objective

The aims of the study were:

• to give a systematic overview of the current knowledge about the user behaviour and its influence on the energy consumption before and after energy upgrade;
• to systematically consolidate existing empirical information about the energy consumption of residential buildings for heating and domestic hot water for different refurbishment states;
• to elaborate proposals how to integrate a realistic, empirically verified assessment of the energy consumption before and after refurbishment in the energy performance certificate;
• to systematically elaborate the possible benefits of energy refurbishment measures beyond the energy saving;
• to elaborate suggestions how to highlight and assess these effects in addition to the current energy performance certificate.

Contractor of the research project was the Institute for Housing and Environment (IWU – Institut Wohnen und Umwelt), Darmstadt, Germany.