This paper explores factors that impact residential adoption of environmental technologies by comparing approaches to technology adoption from economics and psychology. We design a large scale door-to-door field experiment in the spirit of Della Vigna, List, and Malmendier (2009) that identifies the influence of prices, “social pressure” and “curiosity” on the decision to adopt such technologies. We also develop a theoretical model of adoption and perform structural estimation and welfare calculations. Empirical results suggest that both prices and social norms influence the purchase decision and encourage adoption. Interestingly, our results suggest a monetary value for social norms in the range of 30-70% ($1.40 – $3.50) of the $5.00 purchase price for CFLs. However, these factors work on different margins. Whereas social norms have greatest import on the extensive margin, prices work along both the intensive and extensive margins (therefore influencing the number of packages purchased).