The energy crisis has prompted an explosion of interest in how to save energy and reduce bills. While many suggestions are familiar and easy to understand, there are plenty of highly effective behavioural actions that are less well known but no less effective. Indeed some of the most underestimated steps can be the most impactful.
We’ve been reviewing the evidence and have identified five actions households can take that will have meaningful impacts on their energy usage.
1. Turn the thermostat down by a degree or two
Moving thermostat settings from 20 to 18 degrees is by far the most effective measure most households can take. This simple change can reduce your gas bill by over 25%, saving an average UK household £313 per year. Going down just one degree to 19 degrees still represents about 13% saving on your gas bill (about £157 per year). Given the way most homes are heated in the UK, this action will benefit two in three households, and if you are one of the 2.7 million UK households heating their home to a Caribbean-esque 25 degrees, the savings will be even greater.
2. Turn down combi boiler flow temperature
Around half of UK households can save up to 8% of their gas use, around £100 per year, by reducing the flow temperature of their combi boiler (the temperature that your boiler heats the water to before it goes to your radiators). Boilers are often set by default at 70-80 degrees.
This temperature is too high for optimal performance of a condensing boiler, which should be nearer 60 degrees or lower. Turning your boiler flow temperature down shouldn’t make your home any less warm and is something that you can easily do by yourself in a couple of minutes using this step-by-step tool from Nesta that has been used by almost 100,000 people already!
3. Use a water-efficient shower head
Efficient shower heads can reduce hot water usage by an astonishing 40%. Given that around 20% of household gas consumption in the UK is used for heating water for showers and washing up, this action could add up to a typical saving of around £84 a year. Every minute cut from your shower saves about 15 litres of water and if the water is turned down while lathering, that’s another 30 litres per shower saved. This tip is still relevant for electric showers as heating water with electricity can be very expensive.
4. Turn down radiator valves
Even without changing the thermostat, lowering the settings on radiator valves can save over 5% on an annual bill which works out around £70 per year for a typical household. Bedrooms or other occasional-rooms have no need to be heated all day if they are not being used. Turning radiator valves down completely in them throughout the day will save an additional 4% or so, or around £55 per year.
5. Turn down hot water temperature on combi boilers
Using energy to heat up water only for it to be too hot to use and need cooling down with cold water is clearly wasteful. Changing the hot water temperature on combi boilers to 42 degrees reduces the amount of fuel needed to heat water, saving a typical household around £26 or 2% off their gas bill per year.
Does this match with people’s plans?
These suggestions may seem obvious when listed like this but many people don’t know which energy-saving actions are most effective and tend to overestimate some more significant but lower-impact actions. In a quick survey back in August 2022, we asked people what they were planning to do to save energy this year. There were lots of effective actions cited, such as wearing more clothes instead of heating, but also less effective measures such as turning off lights (not a bad thing to do, but modern LEDs are so efficient it won’t save much).
It should be noted that ‘planning to do’ is not the same as ‘thinking it’s effective’. And the survey predated much of the recent media attention on this topic. So how did people’s knowledge of effective energy-saving actions improve? Which ones should we emphasise more in communications? And how did the government’s energy price guarantee affect people’s intentions to reduce their energy usage?
There’s good evidence that the Government and consumer groups can draw on energy-saving advice campaigns so they can focus on highlighting the most effective actions, emphasising less familiar and most likely to be underestimated steps.
Nesta recently commissioned the highly esteemed household energy modelling team Cambridge Architectural Research (CAR) to update their original research on how much energy could be saved by making small changes to everyday household behaviours. Our top five tips above draw upon the new energy-saving research published in October.
From a behavioural perspective, many of our recommendations are – thankfully – one-off actions, which should boost the potential impact of adoption. However we want to know to what extent people may underestimate the impact of the top steps CAR has identified and by how much? We’ll run a series of online experiments to find out over the coming weeks – so watch this space.