3.1. Domestic scale engagement: In-Home Displays (IHDs)

Dr Tom Hargreaves, University of East Anglia


Over the last four decades, sustained attempts to reduce domestic energy demand have struggled to produce significant or lasting results. Getting people to engage with and reduce their energy use has proven extremely difficult. A key reason for this lack of engagement is that, for most people and most of the time, energy is 'doubly invisible' [6]. It cannot be physically seen, and current billing and payment systems also mean it is very hard to connect energy use to particular activities. A popular response has been to provide forms of feedback on energy use through a range of in-home displays (IHDs).

IHDs provide real-time information to householders, letting them know exactly how much energy they are using second-by-second, as well as how much this costs. The intention is that this feedback will enable householders to identify where and when they are using the most energy and thereby take steps to reduce their use.

Studies suggest that IHDs can help people realise financial savings of up to 15 per cent [7], with better results achieved where the feedback is frequent, sustained, appliance specific and given in a clear and appealing manner [8]. These encouraging findings have supported the policy decision to give IHDs to all UK households by the end of 2020 as part of the UK government's £12.1 billion smart meter roll-out.

What's the problem?

While IHDs have considerable potential to help people learn about, and reduce their domestic energy use, a large-scale trial of IHDs in 60,000 homes in the UK, including 18,000 equipped with smart meters, observed no statistically significant savings from standalone IHDs, and just 3 per cent savings when IHDs were combined with smart meters [9]. In either case, these results fall someway short of potential savings.

More in-depth and long-term studies have also cast doubt over IHDs overall effectiveness. While it is recognised that, when used, IHDs do help people to learn about their energy use, it has also been shown that they have only short-term effects, typically just 3-4 months, with people often then becoming bored of them and packing them away [10], that they can negatively influence household social dynamics causing conflict about energy saving as often as cooperation [11][12], and that they may make matters worse by legitimising energy-intensive practices and overlooking those considered non-negotiable [13].

The central lesson from research on IHDs is that many of their problems and limitations derive from over-simplistic assumptions about household behaviour. It is too often assumed that, when given new and better information about their energy use, individuals will make rational decisions and choose to cut their consumption to save both energy and money. The reality, however, is that decisions about household energy use are not made by individuals but must often be negotiated with others. Such decisions that are made are far from rational, but rather involve numerous aesthetic, emotional, pragmatic and other forms of household 'logic'.

Finally, instead of being able to choose freely about how to reduce their use, householders are often constrained by societal expectations about what is normal and non-negotiable.

What's the solution?

Some simple measures may help improve IHDs overall effectiveness. It is clear that, on their own, IHDs are unlikely to achieve substantial and sustained reductions in energy use. Rather, householders must be supported to get the most out of them. For example, IHDs should be carefully explained at installation, and further help and advice should be given to encourage and enable people to act on the information they provide.

It is clear also that a long-term approach is required to keep householders engaged beyond a 3-4 month 'honeymoon' period. For example, IHDs could potentially receive regular upgrades that offer new and more detailed information to ensure that they remain interesting and useful to householders. Further, householders should be encouraged to use IHDs to reflect on what they consider to be non-negotiable to ensure that underlying trends towards rising energy use do not go unchallenged.

Perhaps most importantly, though, getting the most out of IHDs – and of other interventions to reduce domestic energy demand – requires a more in-depth understanding and appreciation of how energy is used in the home. In short, attempts to reduce household energy use should start by trying to understand the realities of everyday domestic life and how energy fits into this, rather than the other way around.