About Nesta

Nesta is an innovation foundation. For us, innovation means turning bold ideas into reality and changing lives for the better. We use our expertise, skills and funding in areas where there are big challenges facing society.

Changing boiler settings to save money

The majority of gas boilers in the UK aren’t running as efficiently as they should. They’re burning more gas, creating more emissions and costing households more money than they need to. Our project is investigating how to encourage and support households to increase the efficiency of their existing gas boilers by lowering their flow temperature – the temperature at which the boiler sends water to the radiators. This could reduce household energy use by 6-8%.

This phase focused on developing a deeper understanding of the barriers households may face in lowering their flow temperature, as well as the most effective messaging to communicate the change, through an online experiment.

What did we do?

We ran an online experiment with the Behavioural Insights Team (BIT) to:

  • determine which messaging is most effective at encouraging research participants to change their boiler settings
  • confirm whether common concerns identified in previous phases of the project were applicable to a larger population/sample
  • identify any new/further barriers households may face in changing their boiler settings.

A sample of 959 participants, representative of the UK's population in terms of gender, age, ethnicity and region of residence, were recruited from the Behavioural Insight Team's participant base. These participants were randomly assigned to see information about how lowering boiler flow temperatures could reduce energy use with a selection of messages:

  • you could save hundreds of pounds each year by changing your boiler settings
  • you could be losing hundreds of pounds each year by not changing your boiler settings
  • small changes can make a big difference to your energy consumption.

There was also a control group that didn’t see any information other than how lowering boiler flow temperatures could reduce energy use. Participants were then asked whether they would consider changing their boiler settings and why they might be hesitant to do so.

What did we find?

Our online experiment found that people were very open to lowering their flow temperature. Not only did 92% of participants who saw the “save money” messaging say that they would do so, but 82% of participants in the control conditions said they would too.

Despite these positive indications, some important barriers were highlighted by participants, who said they were:

  • worried about making a mistake
  • concerned it would make their home colder
  • confident their boiler was already set correctly
  • confused about what changing the flow temperature does
  • satisfied with their current settings so didn’t want to risk changing things.

These barriers closely match the issues identified from our household interviews in the previous phase of this project so it’s particularly reassuring to have our initial findings backed up with a much larger sample.

We also found that people were more motivated to change their settings if shown information with a “you can save money” or “you might be losing money” message, compared to those who didn’t receive any information or saw a “small changes can make a big difference” narrative. This is important for communicating advice in the future.

"Over 80% of householders with combi boilers say they would change their boiler settings to save money."

Conclusion

Whilst consumers are keen to change their boiler settings, they don’t know how or what to do and they want certainty about how it will affect their bills. In the next phase of this project Nesta will:

  • develop clear step by step instructions to help households reduce their boiler’s flow temperature with confidence
  • build the evidence base about which flow temperature to recommend to householders based on housing and occupancy types.

Author

Katy King

Katy King

Katy King

Deputy Director, sustainable future mission

Katy is deputy director on Nesta's mission to create a sustainable future, which focuses on decarbonisation and economic recovery.

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Shaan Jindal

Shaan Jindal

Shaan Jindal

Senior Analyst, sustainable future mission

Shaan is a senior analyst in the sustainable future team.

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Seemanti Ghosh

Seemanti Ghosh

Seemanti Ghosh

Principal Researcher, Evidence & Experimentation team

Seemanti worked in the Evidence & Experimentation team, helping mission teams in the innovation research process and translating that research into policy and practice.

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Andy Marsden

Andy Marsden

Andy Marsden

Design Lead, Design & Technology

He/Him

Andy is the design lead for the sustainable future mission.

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Andrew Schein

Andrew Schein

Andrew Schein

Lead Behavioural Scientist, sustainable future mission

Andrew was the lead behavioural scientist for Nesta's sustainable future mission.

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Oli Berry

Oli is a research advisor in BIT's home affairs, security and Education team. He specialises in conducting quantitative research and has led the design of a number of randomised contro…

Dr Bobby Stuijfzand

Dr Bobby Stuijfzand is a senior research advisor in the Behavioural Insights Team's health and wellbeing team. He oversees the design and evaluation of online experiments and field tri…