Smaller and newer homes use less energy than larger, older ones, confirms a new report by UCL researchers that offers unique insights into household energy consumption across the country.
The report, published by UCL's Smart Energy Research Lab (SERL), analysed the gas and electricity use of more than 13,000 representative households across Great Britain over two years. The report offers a range of insights into overall energy usage, and efforts to improve the energy efficiency and sustainability of households.
The report found that homes built between 1900 and 1929 used an average of 33% more gas per square metre of floor area than homes built since 2003, even though they used comparable amounts of electricity, highlighting the increasing insulation efficiency of modern homes.
Homes over 200 square metres used more than four times as much energy than homes smaller than 50 square metres. However, while larger homes used more gas for heating than smaller homes overall, they averaged to be slightly more efficient per square metre of floor area. This is in part because larger homes tend to have less surface area from which to lose heat for a given volume.
Additionally, detached houses used on average 6% more gas per square metre but 3% less electricity per square metre than terraced houses.
Lead author Dr Jessica Few (UCL Energy Institute) said: "It's very exciting to be able to see from our data how energy use is distributed among Great Britain's households. We hope the report and data released for the first time will be useful to researchers and policymakers looking to tackle the big societal issues we face."
Across Great Britain, the average home has an Energy Performance Certificate "D" rating for energy efficiency, while the governments of England, Wales and Scotland have broadly set a target to bring the average up to at least "C" by 2035. The report found that these D-rated homes consume on average 17% more gas and 3% more electricity per square metre of floor area than C-rated homes, offering insight into how much energy saving these targets can offer.
The team found that homes equipped with solar panels significantly reduced their dependence on grid electricity, but this varies seasonally. In June 2023, households with photovoltaic solar panels exported on average three times more energy back to the grid than they purchased from the grid, while in December these households imported more than 20 times the energy they exported. Averaged over the 11 months where data was available for 2023, homes with solar panels exported on average 4.79kWh per day while using 5.54kWh per day, and the households only needed to draw a net average of 1.12kWh of electricity per day from the grid.
The report also found that households with electric vehicles consumed 70% more electricity than those without.
Co-author and Head of SERL, Professor Tadj Oreszczyn (UCL Energy Institute), said: "The new report really demonstrates the value of having real-world energy use data so that recommendations can be made to policymakers and consumers how to save energy. This could not only save people money and keep them warmer and healthier, but also address the needs to reduce CO2 emissions."
The report covers 2021 through 2023, a period of time that saw significant disruption to the UK energy markets. This included the third national Covid-19 lockdown between January and March 2021, unprecedented rises in energy prices influenced by Russia's February 2022 invasion of Ukraine, and a period of general inflation over 10% between September 2022 and March 2023. In a further piece of analysis using the SERL data, the team found that gas and electricity use were higher in winter 2021/2022 before high energy costs hit the market, with consumers ultimately reducing their gas usage by 12% and electricity usage by 7% by winter 2022/2023.
The study offers a unique glimpse at energy consumption across the country as it's the only project on such a large scale to draw data directly from participating households' smart meters and link it with a wide range of contextual data. This combined dataset allows the team to track energy consumption and compare that usage across a range of factors including time, regions, building types, socioeconomic status, occupancy, heating systems, weather conditions and the presence of an electric vehicle or photovoltaic solar panels.
SERL Director Simon Elam (UCL Energy Institute) said: "We're grateful to the participants who have contributed their data to this and also to UKRI who have funded this important research and energy data resource. Going forward we are looking at ways to share the SERL data more frequently and on other platforms so that we can maximise the utilisation of the SERL Observatory for research and innovation."
This report and SERL is funded by the Engineering and Physical Sciences Research Council (EPSRC).
