Electricity systems around the world are becoming increasingly dependent on flexibility as renewable generation grows and electrification accelerates. Households have a critical role to play—yet participation in demand response programmes, dynamic tariffs, and flexibility-enabling technologies remains far below what is needed to meet 2030 targets. Scaling residential demand flexibility is not only a technical and market challenge, but also a behavioural one.
The IEA estimates that demand-side measures could provide around 20% of total flexibility needs by 2030, but progress to date is insufficient to meet this potential. In the United Kingdom alone, the government estimates the system will require a five-fold increase in the contribution from households and small consumers by the end of the decade. Similar ambitions are shared across Europe, North America and beyond. What is missing is not just the infrastructure, but an understanding of how to motivate and sustain household participation at scale.
The Users TCP Behavioural Insights Platform has now published its concluding deliverable for Phase 3: Applying behavioural insights to unlock residential demand flexibility: Lessons from field experiments and surveys in four countries. This guidebook brings together the results of four large-scale randomised controlled trials (RCTs) and three surveys conducted in Canada, Ireland, the Netherlands, and the United Kingdom, in partnership with utilities including Centrica/British Gas, EDF, Eneco, Energia, and Hydro One. The trials alone reached over one million households across the four countries.
The trials tested a range of flexibility programmes: improving uptake of time-of-use tariffs (Centrica/British Gas, UK), increasing enrolment in a turn-down scheme (EDF, UK), boosting consumption of self-generated solar energy (Eneco, Netherlands), and accelerating adoption of smart thermostats (Hydro One, Canada). Detailed technical reports for each trial are available via the links below. The results show that behavioural interventions can meaningfully increase engagement and, in some cases, significantly reduce peak demand—with enrolled households achieving up to 35% peak reductions during automated demand response events. However, the evidence also reveals important limits: uptake often remains low without the right incentive structures, behavioural effects can weaken over time, and households vary considerably in their ability and willingness to participate.
Based on these findings, the guidebook distils five behavioural principles for policymakers, utilities, and programme designers:
Principle 1: Make flexibility worth the effort. Participation increases when benefits are clear and tangible relative to the effort required. Programmes should simplify enrolment, reduce administrative friction, and present savings in a way that feels meaningful—for instance, as yearly rather than monthly figures.
Principle 2: Reduce perceived risk and uncertainty. Fear of higher or unpredictable bills is a key barrier to participation in time-of-use tariffs. Introducing risk-reducing features—such as bill guarantees, trial periods, and penalty-free opt-out—can increase willingness to participate more effectively than one-off financial bonuses.
Principle 3: Strengthen consumers’ sense of control. Flexibility can feel restrictive, even when it is voluntary and beneficial. Framing programmes as a way to gain control over energy use and bills—backed by clear feedback and transparent programme rules—can increase both enrolment and sustained engagement.
Principle 4: Automate flexibility to sustain participation. Behaviour change is hard to maintain. Automation reduces the need for repeated action and enables consistent participation in the background. The evidence shows that automated demand response can deliver substantial and sustained peak reductions with minimal ongoing effort from households.
Principle 5: Target flexibility to different consumer segments. Households differ significantly in their ability, willingness, and consistency in engaging with flexibility. Effective programmes tailor design, incentives, and communications to different segments—rather than relying on a one-size-fits-all approach—and ensure that vulnerable and low-income households are not left behind.
This guidebook is the final output of Phase 3 of the Behavioural Insights Platform and builds on the Platform’s earlier work, including the 2024 practitioner guidebook on applying behavioural insights to unlock energy demand flexibility. Together, these outputs provide an evidence base for those working to design, implement and communicate residential flexibility programmes in a way that reflects how people actually make decisions.
Download the guidebook
Download the Technical Appendix (individual trial reports)