To reduce energy consumption of households, many appliances contain eco-settings, which when used, reduce energy consumption. However, the effectivity of the eco-settings in reducing energy consumption is hardly tested. Other design for sustainable behaviour strategies like coercion and feedback might be more effective. To test the effectivity of these three design for sustainable behaviour strategies in reducing the energy consumption of washing machines a 2 × 2 factorial design experiment is conducted. A total of 779 European washing machine users were asked to set washing machine controls for three laundry baskets on one of four control panels. The results showed that eco-settings of the washing machines were used for only 15% of the laundry cycles. Respondents presented with coercion or feedback controls consumed 15% less energy compared to those who were allowed to decide whether to use eco-settings. Few people understood the relation of water temperature and the duration of washing machine programs on energy consumption. Feedback can support their decision processes and prevent unintentional and unsustainable settings. Our research shows that energy efficient washing machines are not necessarily leading to energy reductions because eco-settings are only used in a minority of cases. In this survey, only 6% of the potential 44% savings was realised. The results suggest it would be more effective to always use energy efficient settings, preferably together with feedback and scripting of program menus that solicit the use of short cold cycles. For energy efficiency to be effective, a product must be designed for sustainable behaviour of the user./

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This thesis explores why some consumers buy sustainable options and others do not. As well as how this can be altered through targeted marketing communication and design. Sustainable intent is no guarantee for sustainable behaviour, but sustainable intent is also not a necessity for sustainable behaviour. It is the sustainable behaviour that counts. The reasons consumers buy energy-efficient vacuum cleaners makes this clear. Three out of four buyers of energy-efficient vacuum models did buy an energy-efficient vacuum cleaner for other reasons than environmental friendliness. They bought their energy efficient vacuum cleaner for the exact same reasons as those who bought an inefficient model. For neither shoes nor vacuum cleaners, sustainability is a primary buying criteria. On the contrary, there is a bias that sustainability comes at the cost of perceived quality, fashion image or performance. Only when all the main buying criteria are met, sustainability adds differentiation and value. This counts for both “feel” products (such as shoes and clothing) or “think” utilities (such as household appliances and utilities). The highest willingness to buy the sustainable shoe has been reported when the communicated benefit was on personal relevance combined with a green design. Sustainability and the environmental impact of a product is, for most consumers, abstract and distal. More abstract than the present need which will be solved with the new acquisition. It is also hard, if not impossible, for a layman to compare the environmental costs of product alternatives. Results of comparisons are often context dependent and counter intuitive, which may reduce green trust. To make sustainable products attractive to mainstream consumers, it is necessary, like in mainstream marketing, to focus communication and design on the consumers’ main buying criteria. Deliver sustainability but focus the products’ message and design on the general relevance and needs of the customer or user. Communicating sustainable products is most effective when personal benefits are combined with a linked sustainable benefit such as a health or energy cost reduction. Presenting the energy-efficiency of appliances as a result of broader technological advantages is more effective in creating sustainable purchases than emphasising the communication on the products’ environmental friendliness. Design should and can counter the bias and negative performance perceptions of sustainability. Consumers perceive the smaller energy-efficient motors in appliances often as less robust and powerful than energy-inefficient ones. Design can counter this perceived underperformance of sustainability with additional volume and weight which both have only a minor effect on the environmental cost. Sustainable utilities should perform as well and still look robust and powerful as less sustainable variants. Sustainable shoes without leather should be also just as comfortable, breathable and fashionable. Unfortunately, the study after recommendations of buyers of sustainable vacuum cleaners showed sustainable buyers are less positive in their recommendations compared to those who bought unsustainable versions. This makes owners of energy-efficient appliances ineffective in promoting sustainable alternatives, increasing green trust or changing social norms. Differences in satisfaction ratings are not caused by the differences in the energy efficiency of the products but by the differences in the products’ perceived performance, ease of use and value for money. These are all independent of the input power of vacuum cleaners. Additionally, irrespective of the energy efficiency of the vacuum cleaners, higher suction power and increased weight positively mediate the recommendations. Focusing design and communication on these aspects rather than on energy efficiency alone can reduce the perceived green risk and increase green trust in sustainable products. For energy consuming durables, often the largest part of their environmental cost is realised during the use phase. Eco-design legislation to increase the energy efficiency of appliances and cars prescribes the use of eco-settings to reduce energy consumption. Most of the eco-settings usage is optional and, in most cases, defaults to the unsustainable settings after they are switched off. The washing machine study shows only a few percentages of the theoretical energy savings from the eco-setting being realised. The focus of legislators has not been on user behaviour and the effectivity of these energy efficiency measures. The washing machine study shows energy inefficient users consume three times as much energy as energy efficient users (Chapter 5). The comparison of different design for sustainable behaviour interventions showed elimination of the unsustainable settings, combined with feedback on energy consumption to be far more effective in reducing energy consumption. Design interventions are cost efficient to implement and an effective addition to the technological innovations in motor adaptions and insulations. Feedback also teaches new behaviour. Sustainability should be implicit and not explicit if it is not relevant for the products’ performance or image. By focusing design and communication on consumer relevance and behaviour, this thesis highlights that it is possible to increase sustainable consumption among mainstream consumers. @en

Although environmental awareness is increasing every year, and most people say they prefer to buy more sustainable products, many still do not act on their promise at the cash counter. Sustainable products are often still perceived to have lower quality or reduced performance. Recom- mendations of sustainable buyers might reduce this perceived risk of sustainability. In this research, the Net-Promotor-Scores (NPS) and the underlying reasons for such recommendations of 888 vacuum cleaner buyers were analyzed. The buyers of energy-efficient vacuum cleaners were found to be significantly less positive about their purchase. A difference in scores is, however, not caused by the difference in the energy efficiency of the products, but by differences in other drivers to recommend a product, such as perceived cleaning performance, ease of use and value for money. Additionally, higher suction power and increased weight positively mediated NPS ratings, irrespective of energy efficiency. Focusing design and communication on these aspects rather than on energy efficiency alone can be used to reduce the perceived green risk and increase trust in sustainable products. In this way, recommendations of buyers of energy-efficient appliances can be an effective additional tool in increasing sustainable consumption.@en

Although most people claim to prefer a more sustainable product, only a limited number of ‘green buyers’ act on their words at the moment of purchase. To find out how to get mainstream buyers to buy more sustainable products, we used data on 950 Western European buyers of 32 different vacuum cleaner models. The issue was why three out of four consumers bought a less sustainable high input power model when an energy-efficient model with equal specifications was also on offer at the same price. Only 6% of buyers bought their vacuum cleaner for environmental reasons. The remaining 94% of buyers stated that their purchase decision was mainly based on reliability, durability, key features, the brand and value for money, regardless of whether they bought an energy-efficient or -inefficient model. The 73% who bought energy-inefficient vacuum cleaners opted for heavier models (perceived as more robust) featuring bags for dust collection, and were more sensitive to messages addressing technological innovation. Beside energy-efficiency legislation, we see two options to encourage mainstream consumers to buy more energy-efficient products: (1) link technical advancement in innovation to lower power (‘we can create more suction with less energy’) in product branding, and (2) seduce mainstream consumers with models that are redesigned for performance, robustness and durability. With this quantitative consumer research, we add both to the knowledge of buying behaviour in terms of sustainability as well as to the knowledge on how to redesign and market green products in mainstream markets.@en

The quality of life (QoL) of survivors of a myocardial infarction (MI) remains lower than that of their peers long after the acute event. Previous research on this subject has indicated, however, that this difference might lessen somewhat over time for the dimension 'emotional functioning' (as measured by the sickness impact profile (SIP): A generic instrument for QoL). The present study explores this phenomenon further using two instruments that specifically measure emotional functioning i.e. the hospital anxiety and depression scale (HAD) and the heart patients psychological questionnaire (HPPQ). Ninety-nine participants of a large population-based cohort (the Rotterdam study), who had been admitted to the hospital because of an MI in the previous 6-60 months, and 101 reference subjects, without a history of infarction of heart or brain, from the same age and gender-groups, were interviewed twice (at 1- to 3-year time intervals). The results of the present study confirm earlier findings that the emotional functioning (in terms of 'anxiety', 'depression', 'well-being', 'feeling disabled', and 'displeasure') of MI survivors is impaired when compared to their unaffected peers. Moreover, they did not show any improvement in 'anxiety', 'depression', 'well-being' and 'displeasure' over time in the MI survivors. The results did, however, show that the difference between MI survivors and referents became less in time in the dimension 'feeling disabled'. This decrease was partly because MI survivors improved and partly because referents felt more disabled over time. One explanation for this might be that referents (51% aged 70 years and over) had difficulties in adapting emotionally to decreasing levels of physical functioning with increasing age, while the MI survivors tended to adjust to and accept the impairments they had contracted several years earlier.@en