Current energy scenario-building techniques often overlook the influence of lifestyles, emerging non-energy technology, and household preferences on energy use. This oversight results in an overreliance on assumptions about individuals to contextualise quantitative energy consumption patterns and speculations on energy technology adoption, tariff responses, and automation acceptance. In response to this gap, this paper presents an innovative mixed-methods energy scenario-building approach developed as part of a four-year ARC research project. Grounded in social practice theory, critical futures, and design ethnography, this four-phased method integrates household ethnographic data with people-generated foresight to constructively engage with industry-generated scenarios. In the first phase, 46 existing industry energy scenarios were deconstructed into three multi-studies. The assumptions, beliefs, storylines, and interactions within each multi-study were examined in the second phase. In the third phase, these scenarios were reconstructed into four comprehensive 2030–2050 scenarios focusing on digital and energy technologies. The final phase identified new constraints, opportunities, and datasets, enhancing household participation, industry planning, forecasting, and scenario-building processes. This method makes significant contributions to the energy social sciences on multiple fronts. Methodologically, it offers an evidence-based approach prioritising people and their future lives in energy scenarios. Theoretically, it advances sociotechnical conceptual frameworks by integrating social practice theories and design ethnographic foresighting with engineering and economic understandings. Empirically, it provides valuable insights for energy system stakeholders, reducing uncertainties associated with the dynamics of change. This approach ensures the relevance of energy scenarios for fostering better decision-making for the future electricity system.