Instrument-mediated activity: Towards a milieu-centred approach beyond techno-solutionism

BackgroundDigital technologies are promoted to support sustainability transitions, yet their contribution depends on how they are appropriated in activity rather than on technical performance alone.ObjectiveThis article examines the role of technologies in socio-ecological transitions through an activity-centred ergonomics perspective. Drawing on the instrumental approach, it analyses how digital and precision technologies become-or fail to become-instruments for activity in two sectors targeted by sustainability policies: domestic energy management and agriculture.MethodsThe study combines a longitudinal analysis of smart-grid interfaces (SOLENN project) and a cross-case synthesis of four precision agriculture technology (PAT) studies. Although the contexts differ, both are analysed using the same framework grounded in activity-centred ergonomics and the instrumental approach, focusing on epistemic, pragmatic, reflexive, and interpersonal mediations. This framework enables the identification of mechanisms of technology appropriation across sustainability contexts.ResultsTechnological effects do not depend on technical performance alone, but on appropriation processes and instrumental mediations. In domestic energy management, a minority of households stabilised smart-grid interface use when knowledge, motivation, and monitoring practices were present. In agriculture, technologies can support precision, comfort, and temporal flexibility, but also generate reliability work, cognitive load, and transformations in relations with living systems. Across both contexts, findings reveal mechanisms linking use to activity and appropriation.ConclusionsThe findings challenge techno-solutionist approaches by showing that sustainable transitions depend less on technological deployment than on conditions enabling activity. They support a milieu-centred design approach integrating activity, health, collective regulation, and relationships with living environments as sustainability criteria.