Dr. Diego Casado-Mansilla

There are several actions that can be taken to adopt a sustainable lifestyle: recycling, reducing resources or the use of disposable items, avoiding heat or cold leakages depending on the season, switching off electrical equipment or lights when they are not in use, etc.

The environment can ease or hinder these actions. Sustainability in a private setting, where every element is known, and occupants have complete control of each electrical device, seems to be easier than sustainability in common or shared spaces, such as workplaces. In these latter environments, although the motivation or intentions are high, there are barriers to pro-environmental behavior: 1) workers do not pay the electrical invoices and are unaware of energy use and cost; 2) the diffusion of responsibility phenomenon and the shared use of many electrical devices (e.g. photocopiers, thermostats, coffee-makers, kettles, etc.) keep the devices unnecessarily switched on because no one takes the responsibility to switch them off; and 3) there is an overall uncertainty about the most energy-efficient way to operate shared equipment and people doubt if the action they are taking will reduce the ecological footprint (e.g. whether to switch off an electrical device or the room lights if someone immediately after us will use them).

The thesis hypothesis to overcome sustainability barriers in common or shared spaces requires the design of strategies that ease the adoption of long-term energy-efficient behaviors. To this aim, three empirical studies were conducted, one of them longitudinal. The leading actor of each of these studies is the persuasive technology, defined as technology designed to change the attitudes or behaviors of the users through persuasion, built into the shared electrical devices prone to energy-inefficient utilization. Augmenting these devices with persuasive technology was embraced favorably by the participants of the study. Even more insightful was finding that people tend to treat the augmented devices as if they were real people, attributing social characters to them or affiliating with them to create a team relationship towards coping with energy inefficiency in the workplace.

To validate the hypothesis, this thesis contributed to the Sustainable Human-Computer Interaction community (S)HCI in the following ways: 1) combining predictive soft computing techniques with persuasive interaction to cope with energy inefficiency, increasing workers' energy awareness through eco-feedback provided immediately upon performing the energy inefficient action; 2) illustrating that persuasive technologies are propitious, forming pro-environmental behaviour in the mid and long term; and 3) demonstrating that automating electronic devices (i.e. preventing subjects from controlling these devices), in favor of comfort, is associated with a reduction of the participant's confidence in technology as a means to solve all current environmental problems.