Given a choice, consumers will pick the greener one

– In the study, households choose a renewable energy option as its standard.
– It appears that non-monetary incentives can be highly effective in both the household and business sectors.

Here’s an excerpt from this study:

In two large-scale field studies in Switzerland of over 200,000 households and 8,000 enterprises, we found that presenting renewable energy to existing customers as the standard option led to around 80% of the household and business sector customers staying with the green default, and the effects were largely stable over a time span of at least four years.

Electricity consumption had only a weak effect on default acceptance. Our data do not indicate moral licensing: accepting the green default did not lead to a disproportionate increase in electricity consumption. Compared with men, women in both the household and business sectors were slightly more likely to accept the green default. Overall, non-monetary incentives can be highly effective in both the household and business sectors.