According to the survey of Lützelschwab, Steinebach, Steinebach, and Schulte (2021), 57.8 % of respondents from municipalities in Aargau, Switzerland, believe that graphic visualizations of their personal energy expense will motivate them to reduce the energy consumption. Therefore, by designing concrete nudges in the areas of energy consumption in households and transportation, the thesis investigated how the Fit4Digital Smart Service Portal could intentionally influence Swiss citizens' decisions to an environmentally friendly behavior with the help of choice architecture.

Contemporary theories, as well as national and international good practice examples, were reviewed. In addition, seven semi-structured interviews with Swiss and Finnish experts in the fields of energy, environment, and transportation were conducted to help close the research gap. These interview partners were selected because research indicated that the Nordic countries are at the forefront of sustainability (ACCIONA, 2019), and the Swiss interviewees' experiences were relevant to this specifically Swiss bachelor thesis. For the interview transcriptions, manual coding was used.

The findings of this thesis revealed that numerous national and international experiences could be considered and modified for the Smart Service Portal. Furthermore, when learning from good practices abroad, it is crucial to investigate the transferability to Switzerland. In addition, by including the target behavior, target group, drivers, as well as barriers, touchpoints, and resources needed to assess the nudge's effectiveness, the ‘five steps for successful choice architecture’, may ensure that a successful green nudge is created. Based on 42 good practice examples and seven expert interviews, no major deviation in the number of stated NUDGES and MINDSPACE principles was found in the areas of households and transportation. The most frequently used principles in both areas included Incentives, Understand Mappings, Give Feedback, and Salience; the least explored included Defaults, Expect Error, and Commitment. By implementing the eleven concrete nudges, as well as general recommendations and implementation scenarios, Fit4Digital will have a guide to make the environmental section of the web portal both more effective as well as transparent.