Assessing developments in a type of German on-site energy consultation for private homes on the basis of evaluations carried out over a set time period.

Panel: 8. Monitoring and evaluation: building confidence and enhancing practices

This is a peer-reviewed paper.

Authors:
Martin Steinestel, Consumer Association of North Rhine-Westphalia, Germany
Dominik Jessing, Ifeu – Institut für Energie- und Umweltforschung GmbH, Germany
Peter Mellwig, Ifeu – Institut für Energie- und Umweltforschung GmbH, Germany
Reinhard Loch, Verbraucherzentrale Nordrhein-Westfalen, Germany

Abstract

The energy renovation of residential building plays an important role in the German ”Energiewende”. Energy consultation with private homeowners is one of the most important instruments in achieving the ambitious goals of the ‘Klimaschutzplan 2050’, which has been part of the accepted roadmap for the national strategy towards climate protection since December 2016.

The Consumer Association in North Rhine-Westphalia (Verbraucherzentrale NRW) has offered energy consultancy products to their customers since 2008 in three different projects. These include an on-site energy audit for a subsidised fee. The energy consultation is an essential component that is designed to improve the customer’s knowledge about the energy efficiency standards of their buildings, and to develop individual measures to lower energy consumption. An additional thermograph examination was offered in order to reach customers in a different way during several winter periods. The on-site consultation is offered mainly to owner-occupiers with small to medium-sized buildings with up to six residential units.

The results of the energy audits have been evaluated by the Institute for Energy and Environmental Research (ifeu) in collaboration with Kantar Emnid for the years 2008 (MHS project evaluated in 2011), 2013 (KEK project evaluated in 2014), and 2015 (ENeRWin project evaluated in 2016). Each evaluation was based on a survey of 500 customers. In 20-minute CATI interviews the customers answered a set of individualised questions based on the measures conducted. The consistent nature of the surveys throughout the three evaluation periods enables tracking of developments over time. What were the preferred building components for insulation? Which heating systems were installed in which period? How did the energy savings develop?

The results show small but significant changes in the decision-making of the homeowners concerning renovation measures for thermal protection and changes in the heating system.