In face-to-face interactions, advice acceptance depends on how it is presented, as well as a number of social factors. For example, some persons are inclined to accept advice from an expert if they possess little domain knowledge. In contrast, if such advice is unsolicited, persons might only accept advice from a trusted source, such as a family member. Whether these mechanisms also play a role in the recommender context is unknown, even though advice solicitation may be particularly important in domains where a recommender user seeks behavioral change (e.g. energy conservation, healthy eating). This study examines the role of advice solicitation (i.e. whether one asks for advice or simply receives it) and advice source (i.e. either explained in social terms or not) in our 'Saving Aid' energy recommender system. Through a web-based user study with 252 participants, we find that allowing users to solicit advice themselves increases their perceived level of trust with our energy recommender system, compared to users that are presented unsolicited advice. In turn, we find that trust positively affects user satisfaction levels, as well as the number of chosen energy-saving measures. We discuss how system designers should consider how advice is presented and in which context.