Building energy use in COVID-19 lockdowns: did much change?

The lockdowns introduced to prevent the spread of COVID-19 had huge impacts, as people were largely confined to their homes. It could be expected that residential energy use would increase while non-residential decreased, however the picture is not so clear. Here three complementary datasets on different scales are used to explore changes in building energy use during two UK lockdowns: the complete building stock of Great Britain, a sample of approximately 1000 residential buildings, and one of about 24,000 residential boilers. Energy-signature analysis was used for the building data to estimate the changes in demand for space heating and other uses, with the boiler data able to separate space and water heating and explore changes in these. In the 2020 lockdown residential energy consumption for water heating and appliances increased, with decreased use for space heating, resulting in a reduction in total energy use during the heating season. In the 2021 lockdown total energy consumption changed little, however a decrease in the use of gas space heating was observed. The residential changes counteracted non-domestic changes, resulting in little difference in national energy consumption. These results highlight how longitudinal datasets enabled by Internet of Things-enabled devices can be crucial as an evidence base for research. Policy relevance The impacts on national energy consumption of increased time spent at home provide an important context for the pursuit of net zero targets, particularly with the rise in flexible working seen since 2020. That little change was seen overall could be due to the energy use in non-domestic buildings not decreasing proportionately to their decrease in use during national lockdowns, and thus seeking to lower non-domestic energy use to account for lower utilisation of spaces could deliver carbon and cost savings. This could be achieved through measures such as automated switch-off services, demand controlled heating and ventilation, and reduction in space. The finding that drastic changes were not made to home heating behaviours could have implications for future demand-side response schemes, indicating that perhaps occupants are happy to adapt to cooler conditions by achieving comfort in other ways. Keywords: building stock, COVID-19, energy data, energy demand, energy epidemiology, heating, homes, lockdown, working from home, UK