Helping homeowners optimise their boiler flow temperatures with step-by-step advice: results of a randomised controlled trial

This report details results of a pilot field trial exploring the impact of emailing customers simple instructions about how to change their boiler settings.

Nesta developed an online tool that provided boiler optimisation advice. The tool included a step-by-step guide with relevant sections tailored to a user’s boiler control configuration. The tool aimed to help overcome barriers and to increase the chance of individuals successfully turning their boiler flow temperature down.

To assess whether our online tool was successful in helping individuals turn down their boiler flow temperature, we collaborated with Loop. We launched the pilot on 9th April 2022. There were two arms: a treatment group who received our intervention – an email from Loop with a link to our online tool (3,502 customers) – and a control group, who did not (3,500 customers).

We found that:

  • The email increased the proportion of participants who self-reported turning their boiler down (34% in the treatment group versus 19% in the control group – this difference was statistically significant)
  • We did not find evidence that our intervention resulted in a difference between participants' satisfaction with their temperature in the treatment group and control group.

Money Saving Boiler Challenge

Our campaign aims to help over one million households change their combi boiler settings to save energy.

Authors

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…

Steve Buckley

Andy Marsden

Andy Marsden

Andy Marsden

Designer, Design & Technology

Andy is a designer for the sustainable future mission.

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Shaan Jindal

Shaan Jindal

Shaan Jindal

Analyst, sustainable future mission

Shaan joins Nesta as an analyst for the sustainable future team.

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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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