In this article, we examine two novel issues in user requirements analysis for a feedback system on household energy consumption: (a) microgeneration and (b) the “Must, Should, Could, Won’t have” (MoSCoW) method. We report on a qualitative user requirements analysis using the MoSCoW method for the prioritization of user requirements. Fifteen interviews resulted in three user groups that were abstracted into personas with different user requirements. Finally, we show that changes in cutoff values resulted in MoSCoW prioritization changes for a maximum of only 5.9%. These are promising results for the robustness of the MoSCoW method.