Behave Yourself: How E.ON and Savills’ Cardiff office harnessed behavioural science to cut office energy use by more than a quarter

The science behind the experiment

At the core of this experiment, E.ON and Savills were looking to test how a range of behavioural science theories can be used to change employees’ habits and help reduce energy use – from switching off computer monitors and printers at night, to turning off lights and leaving the office thermostats alone.

The set-up of this office proved ideal for the experiment. Each side of the office has its own energy meter, which made it easy to directly compare the impact that small and low-cost nudges can have on our energy use at work, as well as the financial savings to the business, compared to a control group with no nudges installed.

The nudges used varied from simple stickers above light switches prompting people to turn them off, text above heating controls guiding employees to keep it within an advised range to goal-setting ‘contacts’ and assigned energy ambassadors to keep people accountable. The nudges installed were all subtle and low cost to produce, costing less than £50. The experiment was designed and delivered by a team of behavioural science experts from H+K Strategies.

The results

As a result of these nudges, the experiment saw significant reductions in the energy use, with the amount used for sockets and lighting falling by 4%. Meanwhile, with the experiment taking place in the colder autumn months, energy use for heating in both halves of the office saw a rise. However, while the control nearly doubled its usage, the experiment group only rose by a quarter2.

This resulted in a total saving of 26% in energy use for the half of the office undertaking the experiment. When applied to the entire office, over the course of a year, this represents an energy saving big enough to run an office of 81 laptops for 8 hours a day for a year.

These figures are significant when compared to other similar experiments to reduce energy use, which typically achieve 3-5% decreases. For example, a programme undertaken in the United States using letters comparing consumers’ energy use to other households saw just a 2% reduction3 in energy. Moreover, when considering the fact that the Savills office used for the experiment already had a building management system, this experiment demonstrates the powerful role behavioural science has to play in energy saving.