Question to the Department for Energy Security & Net Zero:

To ask the Secretary of State for Energy Security and Net Zero, pursuant to the Answer of 10 March 2026 to Question 116783, on Energy: Housing, what assessment his Department has made of the aggregate impact on total household energy consumption of voltage reduction technologies installed in domestic properties, taking into account (a) the proportion of appliances that are power-controlled and resistive, and (b) likely behavioural responses by consumers to any reduction in appliance performance.

The lowering of voltage only reduces electricity consumption with resistive appliances. a)The relative proportion of appliances that are power-controlled vs resistive is moving in favour of power-controlled appliances due to changes in technology. For example, filament bulbs, electric bar fires, immersion heating and older white goods are resistive, but more efficient LED bulbs, heat pumps, EV chargers and modern white goods with asynchronous motors are power controlled. b) The department has not conducted studies of consumer responses to poorer performance from their resistive appliances due to lower voltages.