Energy use in buildings in the services sector 2011

The population and sample for this survey is based on the central register for properties in Norway Matrikkelen, where relevant types of buildings within the services sector defined the population. The survey for 2011 is the second survey of this kind by Statistics Norway (SSB), the first was for 2008. Low answering per cent is a challenge for this kind of survey. This is among other things due to quality problems in Matrikkelen, difficulties to reach the correct receiver of the questionnaire because of different owner of the property and the building, and the owner of the building sometimes don’t know the energy use if the building is hired out.

To increase the answering per cent and the quality in the data material several measures was made, and as a result the answering per cent of complete accepted questionnaires increased from 33 per cent for 2008 to almost 50 per cent for 2011. Total energy use for the buildings reporting data for 2011 was 3.6 TWh. This is about 12 per cent of the total energy use in buildings within the services sector.

Average energy use for all the buildings included in the survey was 229 kWh/m2 heated area in 2011, but it is large differences between different types of building. Time of use of the buildings and the amount of energy demanding technical equipment are important to explain the energy use, and the different building types are very different in that respect. This is one of the explanations for the high use of energy in hospitals, with an average in 2011 of 366 kWh/m2. Another extremity in this respect is schools, kindergartens and chapels with relatively limited time of use of the buildings and low amount of energy demanding technical equipment. About 77 per cent of the energy use was electricity, 18 per cent was district heating, heating oil 3 per cent and natural gas and biofuels together 2 per cent. A comparison between offices in different sectors indicated that governmental sector used 196 kWh/m2, while private sector and municipal sector used 209 kWh/m2.

In this report it is also looked into the correlation between use of energy and types of heating and cooling systems, building year, measures for energy efficiency and so on. For buildings with central heating systems the average energy use was 239 kWh/m2 in 2011, while buildings without this used 200 kWh/m2. It was used 231 kWh/m2 in buildings without heating pumps while it was used 223 kWh/m2 in the 16 per cent of the buildings using heating pumps. Also, the statistics indicated that buildings using energy for cooling of living rooms used substantial more energy and newer buildings used slightly less energy. The surveys for 2008 and 2011 showed increased use of water-borne heat during this period, from 38 per cent in 2008 to 44 per cent in 2011.

The need for energy is depending on the temperature. Temperature- and place adjusted energy use adjusts for this, and indicate about the same energy use in both of the relatively warm years 2008 and 2011.

Project financing: Norwegian Water Resources and Energy Directorate (NVE), Enova and Directorate for Building Quality (DiBK).