This article studies the work performed by technicians in a large demonstration project, EcoGrid 2.0, in the Danish island Bornholm. Based on observations of household visits conducted by technicians, we demonstrate how these act as ‘middlemen’, mediating and linking together the smart technology of the demonstration and the involved users. Formally, technicians’ work is to keep users online; however, they also perform a number of invisible tasks to keep users engaged and active. Our ethnographic study shows two broad categories of invisible work: first, technicians continually facilitate the willingness of users, recurrently affirming the social contract between users and demonstration project. Second, technicians facilitate the abilities of users by improvising informal training sessions of how to operate the system. These findings are used to discuss the importance of invisible articulation work of technical service workers in large scale real‐world experiments.