BAU-R-3:Specific energy consumption for space-heating by private households

The picture shows a man in a construction helmet squatting on scaffolding and attaching an insulation board to the wall of a house. Click to enlarge
Good building insulation also provides protection from summer heat.
Source: Photograph: © mitifoto /

2019 Monitoring Report on the German Strategy for Adaptation to Climate Change

Table of Contents


BAU-R-3: Specific energy consumption for space-heating by private households

The decrease by 2014 in temperature-adjusted energy consumption for space-heating suggests that apart from behavioural changes and the increasing use of more efficient heating systems, there has also been a successful implementation of construction measures for heat protection. These measures also have beneficial impacts on the protection of buildings from overheating in summer. Since 2015 the temperature-adjusted energy consumption for space-heating has increased again.

Three lines represent the specific energy consumption of private households for space heating for the years from 2000 and 2017.
BAU-R-3: Specific energy consumption for space-heating by private households

Three lines represent the specific energy consumption of private households for space heating for the years 2000 and 2017. The time series is indexed. In 2000, the values are set to 100. The living space used increases significantly. The energy consumption for space heating (temperature-adjusted) per used living space shows a quadratically increasing trend, the energy consumption for space heating (unadjusted) per used living space shows a significantly decreasing trend. The two values mentioned drop from 100 to 71 and 76 respectively in 2017.

Source: StBA (environmental-economic accounting)

Climate-adapted buildings – heat is kept out

Climate-compatible urban planning and design safeguarding the retention and enhancement of inner-city green space is one approach towards avoiding or at least mitigating heat stress. Other measures approach the issue by tackling the extant building stock.

In order to protect interior rooms from overheating, active technical cooling methods are used in living and working premises. During the hot summers of recent years, this response was also applied in Germany. There was an exceptionally high turnover in mobile air-conditioning units for active cooling in apartments and houses. It must be said however that the use of air-conditioning is associated with increased electricity consumption which, in turn, leads to increased CO2 emissions, in cases where the energy system is still mostly based on fossil fuels. This obviously runs contrary to climate protection efforts. In addition, the abstracted air from air-conditioning systems warms up the local urban atmosphere thus exacerbating bio-climatic problems. Passive cooling measures should therefore be given greater priority both in refurbishing extant housing stock and in the design of new developments.

In order to safeguard the interior climate and protect it from summer heat by means of structural measures, developers and architects will have to pursue two strategies concurrently. The first strategy is that the interior of a building is prevented from heating up in the first place, while the second ensures that warmth existing indoors is discharged to the outdoors with a minimum of energy expenditure. The latter can be achieved e.g. by natural aeration or ventilation systems, controlled nocturnal aeration, or counter-cyclical storage / discharge of hot or cold air. Examples for a pre-emptive protection of buildings from summer heat – the first strategy – include the careful design of window surface area proportions as well as the orientation of the buildings, to use external shade-giving elements and anti-sun glass, to green the façades and roofs of buildings or to provide buildings with good heat insulation, and last not least, to ensure conformity with high construction standards.

Measures taken to ensure structural heat protection also serve to reduce the energy consumed ín the heating and cooling of buildings. In new buildings, requirements regarding heat protection are taken into account in the design and construction stages. In older buildings, energy-related refurbishment improves heat protection: in Germany approximately 1.4 % of building stock dating back to before 1979 are currently being modernised in this way.50 These and other passive measures are capable of pre-empting the overheating of interior rooms. Alongside efficiency-enhancing measures and behaviour-related savings resulting from an increasing awareness of rising costs and environmental concerns, such developments are reflected in distinctly reduced energy consumption by private households in respect of space-heating. The reduced energy consumption in respect of space-heating may also suggest that there has been a change in the prerequisites for cooler indoor temperatures during periods of great heat.

Whether all measures mentioned above are implemented successfully, will be revealed by an examination of the progress made nationwide after adjusting for temperature differences, i.e. an arithmetical examination of the mean progress made in terms of private households adapting their heat energy consumption to the prevailing air temperature. However, it is not possible to make any other than rudimentary statements regarding the resilience of residential buildings in respect of overheating in periods of great heat. The same applies to premises not used for residential purposes which are not covered by this indicator.

In 2000, households still used (after adjustment for differences) more than 580 terawatt hours of heating energy; by 2016 the energy consumption had temperature decreased to 471 terawatt hours. With reference to the living space which increased markedly over the same period, this constitutes a significant decrease in temperature- adjusted energy consumption for space-heating by just under 20 %.

50 Cischinsky H. & Diefenbach N. 2016: Datenerhebung Wohngebäudebestand 2016 – Datenerhebung zu den energetischen Merkmalen und Modernisierungsraten im deutschen und hessischen Wohngebäudebestand. Forschungsbericht eines durch das Bundesinstitut für Bau-, Stadt- und Raumforschung sowie das Hessische Ministerium für Wirtschaft, Energie, Verkehr und Landesentwicklung geförderten Vorhabens. Darmstadt, 179 pp.



BAU-R-1: Recreation areas

BAU-R-4: Funding for building and refurbishment adapted to climate change



Better adaptation to higher average summer temperatures and occasional extended hot periods in terms of building design and building technology (DAS, ch. 3.2.2)