Uptake of green-energy by households remains suboptimal. This was the first study to apply the Prototype Willingness Model (PWM) to understand this behaviour. Participants (N = 454) completed an online survey with measures of the PWM constructs. Attitudes and injunctive norms predict intention; and prototype similarity, favourability and descriptive norms predict willingness to use green-energy. Intention and willingness predict green-energy uptake. Findings supported the use of the complete model to understand this novel behaviour. Future research should test interventions targeting attitudes and injunctive norms to increase intention; and prototype similarity, favourability, and descriptive norms to increase willingness to uptake green-energy.