Gamified persuasive system design refers to design solutions at the intersection of gamification and persuasive technology aiming at influencing attitude and behavior change. Although both concepts have been successfully applied in many domains to increase end-user engagement and satisfaction, results are often mixed and highly context specific. Consequently, there is a dearth of knowledge on how to design those solutions and how they are perceived by different types of users within certain application contexts. Thus, this paper investigates the relationship between the HEXAD gamification user types and persuasive principles within the context of energy saving. First results reveal (n = 206) that, three out of six persuasive principles (Reciprocity, Consistency & Commitment, Liking) have been perceived as persuasive by identified HEXAD user types, which highlights the importance of such user types models. Finally, this paper contributes to the present body of gamification literature by providing a human computer interaction (HCI) perspective which highlights guidelines for designing gamified persuasive systems to incentivize energy-saving.