Observing the unobservable: a field experiment on early adopters of a climate-friendly behavior

Encouraging rapid and widespread adoption of non-normative climate-friendly behaviors represents a crucial challenge for practitioners and policymakers alike, and a new frontier in the transition to a greener economy. Yet, several such behaviors are unobservable and undertaken privately. We devise a novel approach that makes household renewable energy use visible to peers through yard signs and window clings, thus creating social rewards for early adopters and sending a signal within their communities. We implement a field experiment comprising over 20,000 customers of a renewable energy utility in the United Kingdom and find that a significant proportion are intrinsically motivated to put their invisible climate-friendly behavior on display. Indeed, participation and display are identical across treatments with and without a financial incentive.