We estimate short-run electricity demand responses to price changes for Norwegian households from 2023 to 2025, using continental solar and wind forecasts, and hydrological inflow to instrument supply-driven price variation. The presence of several instruments for the price changes allows us to explicitly test the margins at which substitution happens. Households’ electricity substitution is real but coarse: households mostly choose between day and night consumption with a price elasticity of 0.073. Substitution across hours within these blocks, or across days, is more limited.