Simple, clip-on, smart meters show households how much electricity they are using at any moment in time. This feedback has been shown to help people reduce the amount of electricity they use.
Talybont-on-Usk would like to reduce the energy its 300 homes consume as well as generating more of its energy from renewable sources such as the Talybont Reservoir hydro-electric turbine.
At a national level, the government and electricity suppliers are considering how to introduce smart meters across all UK homes. The relative benefits of different kinds of smart meter and the costs involved are the subject of ongoing debate and 2 year trials.
On a small scale, The Prospectory, in collaboration with Talybont Energy , ran a trial equipping 10 households in Talybont-on-Usk with Efergy smart meters for a month. The primary aim of the trial was to explore the psychology of electricity use in the home and how smart meters affect people’s understanding, attitudes and behaviour. We therefore conducted in-depth interviews with each household at the end of the trial and analysed all the reported comments. The trial also measured the effect of the meters on consumption in comparison to a group of 10 control households.
The meters had an effect. 9 of the 10 trial households reduced their consumption during the trial period by an average of 9%. In contrast, the control group consumption rose by an average of 5% over the same period. The variation in consumption between households of similar type and occupancy was striking as was the variation in people’s day to day use. This makes any concept of ‘normal’ consumption difficult.
The story behind the numbers was more complex. Two of the households who reduced their consumption didn’t use the smart meter and two of the households who used the meter didn’t reduce their consumption. The behavioural results explain these findings to some extent.
In most households, the meters had a dramatic effect on people’s understanding and awareness of the electricity they use in their everyday lives and activities. Seeing the readings jump up and down as appliances were switched on or off had the biggest effect on people’s thinking and stimulated conscious changes in the ways they used kettles, lights, auxiliary heaters, showers, washing machines, tumble dryers and ovens. It also encouraged them to turn devices off when not in use.
The meters had the most effect in households where their discretionary electricity use was fairly high and they were motivated to reduce it for either environmental or cost reasons. In the absence of such motivation, it is not clear that meter feedback alone will affect change.
The trial revealed some of the challenges for future smart meter design and technology:-
1. People struggled to monitor their usage over time. They lacked useful reference points and the day to day variability made trends hard to spot.
2. Smart meters can’t (currently) identify which appliances are on and how much each is contributing to the overall load.
3. Understanding electricity consumption is a tricky cognitive problem involving the concept of power x time. Most people will not devote much time or effort to studying numbers and graphs and the drama of seeing consumption readings jump up and down in response to kettles and hairdryers can distract people from identifying appliances which contribute a larger load over a longer period of time.
On the basis of our findings, we would recommend that only the data collection and transmission part of the problem is standardised in UK homes. The design of display appliances should be left open to encourage innovation and competition between both appliance designers and energy suppliers.