The world’s climate is changing and the UK is committed to an 80% reduction in greenhouse gas emissions by 2050.

Around half of our emissions come from buildings, so half of the cuts will have to come from the built environment. But emissions targets will only be met if people start using energy in different ways.

Many people aren't sure if a television uses more power on standby in a year than is used watching it. Understanding how fuel efficient our homes are, in terms of kw/hour per m² of the house, is much more complex.

How we can reduce energy use within buildings

There are three main approaches to reducing energy use within buildings:

  1. Physical controls – can work well, but aren’t always cost-effective. Equipping windows with sensors and motors would cost around £100 per window, which would take some time to recoup.
  2. Policy controls – ideas such as enforcing times when appliances can and cannot be run are difficult socially and politically. When California tried to impose a state-wide reduction of 1°F in air-conditioning temperature settings, there was public outrage and resistance.
  3. Behavioural change – persuading building occupants to change the way they consume energy has more chance - economically, socially and politically - of achieving significant energy reductions.

Previous studies of behavioural change to energy consumption have suggested reductions are achievable, but aren’t often sustained in the longer term.

Achieving sustained reductions requires a different approach – prioritising relevance over quantity of information – that has an effect beyond any temporary interventions or campaigns.

Energy ENLITENment

The ENLITEN project is investigating a three-step process to encourage people to change their long-term behaviour regarding domestic energy use by providing contextually relevant information and responsive energy tariffs.

Monitoring energy use

Sensors are being installed in 200 homes that are capable of detecting humidity, temperature and whether radiators or TVs are on, to get a good idea of how people use energy in their home.

The data from these sensors is used to inform personalised feedback that’s based on the individual’s house, rather than a generic ‘typical’ one.

Contextually relevant information

Home energy smart meters have been around for some time, but they haven’t made a great deal of difference to household energy consumption, because:

  • they only show instantaneous power usage.
  • their data representation is more intelligible to engineers than householders.

By taking sensor data, using it to establish energy consumption patterns, and suggesting actions that could reduce bills, households would be able to see how a shift in their behaviour could save them money.

Tablet computers with different configurations of wording, diagrams and user interfaces will be trialled with households, to see which versions users touch the most.

Making monitoring feedback more relevant

Instead of graphs or pie charts showing instantaneous power usage, simple sentences that highlight potential actions might be more useful, like:

We’ve noticed your boiler is on between 8-10am, but you leave the house at 7:30. We’ve projected this over a year and believe this is costing you £95. You might want to reset your timer clock.

Responsive energy tariffs

In the future, electricity prices won’t be static. A lot of the cost of energy is the overhead of the infrastructure capable of carrying peak demand, rather than fuel. So, as energy prices rise and the technology becomes more available, it’s likely that energy providers will offer instant, incentivised tariffs.

A tablet linked in to instant tariffs could tell a householder that if they delayed putting on their washing machine by 45 minutes, an energy supplier would charge them 3p per unit instead of 14p per unit. People might willingly press a button, change tariff and save money.

Increased energy literacy can make a world of difference

Between identical households – with the same income, number of people and type of house – there’s a fourfold difference in the amount of energy use between the most wasteful and the most efficient of them.

So, we know that if we can change user behaviour we can save a great deal of energy through buildings.

By better understanding people’s knowledge about energy, information can be tailored to the terms that make sense to them, helping them make more informed energy choices and effect long-term change in their energy consumption behaviour.