A- and B-rated dwellings used 42 kilowatt hours of electricity per square metre in 2021 compared with 75 kWh for C-rated dwellings, 79 kWh per square metre for D and for E and 67 kWh per square metre for F- and G-rated dwellings, according to CSO new data.
The mean electricity consumption in 2021 for dwellings built in 2005-2021 was 48 kWh per square metre, which was around two-thirds of the figure for dwellings built in 2000-2004 of 75 kWh per square metre.
Mean electricity consumption decreased in 2021, compared with 2020, for apartments and mid-terrace houses but it increased for end-of-terrace houses, semi-detached houses, and detached houses.
A detached house used 8,039 kWh of electricity in 2021 which was 70% higher than the corresponding mean electricity consumption for a mid-terrace house.
More energy-efficient dwellings also had more floor area. A- and B-rated detached houses had an average of 230 square metres, compared with an average of 89 square metres for detached houses with an F- or G- rating.
Statistician Dympna Corry said it was the first time the CSO had combined datasets on metered electricity consumption and domestic building energy ratings.
This analysis examined households that had a BER and used electricity as their main space heating fuel.
Dwellings with better energy ratings used less electricity per square metre of dwelling floor area, she said.
“F- and G- energy-rated dwellings had the lowest mean electricity consumption figure in 2021 indicating that factors other than energy ratings – such as disposable income, whether the house was adequately heated, and use of secondary heating fuels – may have had an impact,” the statistician said.
However, electricity is used less than gas as a main space heating fuel.
The mean electricity consumption was lower in 2021 than in 2020 for apartments (-3.1%) and mid-terrace houses (-1.6%), and higher for end-of-terrace (1.6%), semi-detached (2.6%), and detached houses (6.2%).
Average electricity consumption per dwelling varied considerably more by household type than by energy efficiency rating.