We use a discrete choice experiment to quantify whether superannuation fund members would be willing to accept lower returns for higher allocations of renewable energy in their portfolios. Mixed logit modelling provides evidence that this willingness is driven by a fund member’s environmental sentiment. Latent class modelling suggests that two classes of superannuation fund members exist: those whose preferences align with a renewable energy transition and those who are focused on financial returns. Our results suggest that the understanding of fiduciary duties, to act in the best interests of members, should be broader than a singular focus on financial returns.