Solar Motivation Data 2023

Published: 4 July 2023| Version 1 | DOI: 10.17632/36vpnpfzvy.1
Lisa Legault


Although a small body of research has examined the motivational foundations of homeowners’ decisions to adopt rooftop solar panels, in this research we compare adoptive and non-adoptive homeowners (N=824) across a spectrum of values and motives to identify the most salient predictors of solar adoption within various demographic and political strata. Results of hierarchical logistic regressions reveal that altruism negatively predicts solar adoption while both autonomous (i.e., internal) and controlled (i.e., image and status based) motivation toward the environment are positive predictors. Importantly, however, these main effects are qualified by several key interactions. In particular, although altruism negatively links to adoption for younger homeowners, it is positively associated with adoption for older homeowners. Similarly, controlled motivation predicts solar adoption for both younger and higher income homeowners, but it is not a predictor for older and lower income homeowners. In addition, autonomous motivation and education predict solar adoption for Democrats, but not for Republicans. We highlight the importance of assessing interactions between demographics, on one hand, and motives and values, on the other, in order to reveal differences in the motivations of different types of adopters. These findings underscore the importance of more targeted solar policy, marketing, and public messaging.


Steps to reproduce

We sought to understand differences between homeowners who have installed rooftop solar panels versus a matched group of homeowners who have not installed solar panels. We were interested in three key categories of predictors: 1) established demographic correlates of adoption, including income, age, and education; 2) basic human values, including altruistic, egoistic, and biospheric values; and 3) motivation toward environmental behavior, including autonomous motivation (e.g., caring about nature and the environment), controlled motivation (e.g., to follow the trend, to keep up an image), and amotivation (i.e., no interest in positive environmental behavior). In addition, we examined the covariates of both political orientation (i.e., lean) and interest in innovation. We sought to assess the unique role of each value and each motive in predicting the likelihood of solar adoption, in order to address current debates about the relative importance of values versus motives in proenvironmental behavior (see Steg 2016; Mason & Otto, 2021). We expected that environmental motivations would be more important predictors of solar adoption than broader values, because of their motivational proximity to the behavior in question (Legault 2023). However, we expected the effects of motivations on solar adoption would be qualified by interactions with key demographics. We reasoned that because solar adoption is a complex environmental behavior imbued with multiple competing goals and incentives (e.g., Noppers et al., 2014; 2016), it is unlikely to be explained by a single set of core motivational factors, and that there are indeed different types of solar panel buyers. Thus, we sought to test the moderating effects of age, education, and income on links between motivation and adoption. However, we specified confirmatory hypotheses only for income – given new research suggesting that low income adopters may care more about the environment than high income adopters (Wolske, 2020). We expected those with larger incomes might adopt solar for more external reasons, for instance to be recognized by others or to signal status and wealth, compared to those lower in income. Similarly, because solar panels are expensive, those with financial means may be most likely to invest in order to save more money long-term, and thus their primary motivation is likely to be more financial than pro-environmental in nature. In contrast, those lower in income might invest in solar for more diverse reasons, including autonomous proenvironmental motivation (Palm, 2020; Wolske et al., 2017). Indeed, when people lack disposable income to afford solar panels, the decision to adopt might be driven more strongly by genuine care and concern for the environment. Said differently, because investing in solar is more financially costly for these individuals, proenvironmental concern is likely to be a stronger predictor of solar adoption.


Clarkson University


Environmental Psychology, Motivation, Values