AN INTERVENTION STUDY ON SPILLOVER EFFECTS IN PRO-ENVIRONMENTAL BEHAVIOURS IN SINGAPORE

Abstract

In response to rapid climate change, there is an increasing need to study and promote Pro-Environmental Behaviours (PEB) affecting energy conservation. Researchers in the field have found that it is possible for individuals to adopt or increase PEBs not targeted by an intervention through a phenomenon known as ‘spillover effects’. The study consisted of a four-week field experiment conducted in Singapore, with a final sample size of 146 households divided into four experimental groups – Control Group, Financial Incentive Group, Assigned Goal Group and Self-Set Goal Group. Participants in the intervention groups were tasked to reduce electricity by a percentage either assigned to them or set by them, and those in the Financial Incentive group were promised cash vouchers upon hitting their assigned goals. To identify for spillover effects, the gas, water, food, and transport behaviours of participants were analysed, although participants were not requested to be more conservative in these domains. Over the course of a four-week study, weekly utility meter readings and data from three sets of surveys were collected. The results have shown that participants in the Financial Incentive Group reduced the most electricity but produced little to no spillover effects, while participants in the Self-Set Goal Group produced the most spillover effects while also reducing a significant amount of electricity. Thus, of all the interventions studied, allowing participants to self-select their own goals seem to be the most effective in promoting PEBs.