Share the Warmth: Using behavioural insights to reduce energy usage among homeowners

To effectively support homeowners in adopting energy-saving behaviours and reducing their bills, the LGA funded a consortium of nine local authorities from Kent and Medway and the NHS in collaboration with The Behaviouralist to develop an intervention that leveraged behavioural insights to encourage local residents to reduce energy usage at home.

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The challenge:

The increase in global energy prices has put a significant burden on UK households in recent times. Local councils across the UK and the NHS are facing a rising demand for advice regarding energy reduction and an increase in complaints due to the limited support and funding available. While there are low-cost and low-effort actions that can help households save hundreds of pounds on their annual energy bills, behavioural barriers often prevent people from adopting them.

The solution:

To identify the barriers, the consortium drew on the Capability, Opportunity, and Motivation – Behaviour (COM-B) model and performed three preliminary research tasks (including a residential survey (N = 1,903) to examine homeowners’ attitudes and beliefs linked to different energy-saving behaviours, interviews with experts working in the energy domain to obtain a deeper understanding of the common challenges associated with saving energy, and an extensive literature review on barriers associated with reducing energy use at home).

Based on the identified barriers, the consortium developed Share the Warmth - a behavioural intervention that aimed to empower residents and their close ones to save energy at home. The intervention was designed to address five key behavioural barriers:

  • Lack of trust: people may be more likely to take energy-saving advice from friends and family than from websites or government-led initiatives. The intervention encourages residents to act as trusted messengers and help their families, friends, and neighbours save energy.
  • Language and cultural barriers: residents who join Share the Warmth share energy-saving tips with their friends and family in a language and under cultural norms that are appropriate.
  • Time constraints: many people do not have sufficient time and mental resources to think about how to save energy at home. The intervention prompts residents to reach out to their time-poor friends and relatives and help them implement the tips.
  • Information overload: many residents might feel lost in the sea of information on energy saving available on the Internet, not knowing what actions are most effective. The intervention promotes five key tips that are simple to implement, even in other people’s homes.
  • Perceived costs of energy efficiency improvements: people might incorrectly believe that energy savings can only be achieved through significant upfront investments. The intervention promotes five tips that cost little money and effort to implement and can save the resident more than £500 per year.

The main objective of Share the Warmth was to teach residents five low-cost energy-saving actions and to empower the residents to help their friends and family to implement these measures. Once on the Share the Warmth website, residents were shown five energy-saving tips, took a quiz to test their knowledge, and planned who they could help. The five energy-saving tips were:

  • Lowering the boiler’s flow temperature to 55-65C
  • Setting the thermostat to 18C
  • Adding radiator reflective panels
  • Using a water-efficient shower head
  • Moving furniture away from radiators

The intervention emphasised helping individuals who may not be able to take energy-saving actions on their own (e.g., the elderly, disabled, and time-poor individuals). The consortium designed the intervention to answer the following research questions:

  • Does providing a short online training increase people’s knowledge of how to effectively save energy at home?
  • Which behavioural messaging strategies are most effective in getting people to commit to sharing energy-saving advice with others?
  • Are those who participate in Share the Warmth more likely to help their close ones implement energy-saving measures than those who do not participate?

To evaluate the effectiveness of the intervention, the consortium evaluated different versions of the Share the Warmth platform in a randomised controlled trial (RCT). Specifically, we randomly varied (1) whether participants received the energy-saving quiz before or after learning about the energy-saving tips, and (2) which behavioural message participants were presented with when being asked to share the warmth with others. The three behavioural messages were as follows:

  • Social norms (where we highlight that the majority of other campaign participants have committed to sharing the warmth)
  • Altruistic appeals (where we appeal to participants’ intrinsic motivation to help others)
  • Ease of the action (where we emphasise that helping a friend or a family member to take an energy-saving action takes little effort)

The randomisation allowed the consortium to understand the extent to which the intervention increases participants’ energy-saving knowledge, and identify which message is most effective in getting people to commit to sharing the warmth.

The Share the Warmth intervention ran between 7th November 2022 and 31st January 2023. Residents were invited to join the challenge and visit the Share the Warmth website ( The promotion was primarily done via local council social media (i.e., Facebook, Instagram, Twitter, LinkedIn, and NextDoor), resident and staff newsletters, and printed posters displayed in public spaces in Kent and Medway (e.g., in libraries).

Throughout the project, a series of eight monthly workshops were conducted by The Behaviouralist to introduce the consortium to behavioural science research. The workshops provided the councils with a hands-on opportunity to take part in the design and development of the campaign.

The impact:

Our analysis yielded three key findings:

  1. Sharing energy-saving tips has a significant positive effect on participants' energy-saving knowledge. We found that those in the treatment group performed better in the knowledge assessment – on average they scored 39% higher than the control group. We also found that while most participants only spent a short amount of time reading the tips without watching the videos provided with the tips, it was sufficient to considerably increase participants’ energy-saving knowledge.
  2. Prompts that leverage social norms appeared to be more effective in getting participants to commit to sharing energy-saving advice with others. We found suggestive evidence that a norm-based prompt led to 14.1-18.1% higher commitment rates, compared to the other two prompts which leveraged altruistic appeal and ease of implementation. This adds more evidence to the idea that people are more willing to participate when they are aware that others are doing the same.
  3. Residents who participated in Share the Warmth appeared to be more likely to help their friends and family than those who did not participate, indicative of a positive impact of the intervention. Based on self-reported data that was collected through an evaluation survey, a higher proportion of participants (89.3%) than non-participants (32.1%) reported that they had helped others reduce energy bills in the past four weeks. Among those who helped, participants reported having helped on average more households (as well as more lower- to middle-income households) than non-participants. Compared to non-participants, participants also reported a higher likelihood of helping others save energy in the future.

How is the new approach being sustained?:

  • Key topics and exercises covered in the monthly workshops will be taken forward within the local councils for encouraging energy-saving behaviours as well as other challenges.
  • A checklist that helps practitioners determine whether an RCT should be used to evaluate an intervention and that provides a realistic estimate of the work and resources required to deliver an RCT will be circulated.
  • Opportunities to continue working together within this network on other behavioural change challenges will be explored. Initial ideas for potential collaboration include reducing water consumption, increasing the uptake of vegetarian meals in schools, encouraging the reuse, repair, and recycling of Waste from Electrical and Electronic Equipment (WEEE), and promoting reusable takeaway packaging.
  • Other councils will be encouraged to partner up as a consortium for future projects.

Lessons learned:

Improving engagement rates across different demographics:

  1. The campaign could better target young people and other communities who are inclined to help older people by making use of offline communications - although this would take more time to plan and implement - or through social media platforms most frequented by the younger population (e.g., using TikTok rather than Facebook).
  2. Better incentives could be put in place to encourage participation (e.g., by adding more social elements to helping others implement energy saving tips).
  3. Enrolling on the campaign could be made easier (e.g., people would simply enter their name and who they want to help) - but this may risk a total lack of commitment.

Sharing energy-saving tips:

  1. Sharing tips had an impressive positive effect for teaching people new information. Future campaigns could continue applying them even for non-energy related programs.
  2. Clear and concise communications may be key when sharing informational tips.
  3. The key to getting more people to read the tips may be to reach out to them at a time when they are actively looking for energy-saving information (e.g., after they receive their energy bills).

Increasing participants’ commitment to sharing energy-saving advice:

  1. Further research should be conducted on the effectiveness of social norm-based messaging on the promotion and uptake of commitment campaigns, as our findings here are only suggestive.
  2. Councils should look for more opportunities to highlight the positive behaviour of others.
  3. Among those who did not commit, low relevance of the tips was cited as the top reason (e.g., not everyone has a combination boiler, or a person cannot afford to turn their thermostat on at all). Future campaigns could increase the relevance by providing a larger number of tips, and potentially offer information that is not as readily available.

Contact person for the project: Laura Taylor ([email protected])