The reduced environmental footprint of bicycle sharing systems (BSS) is one of the reasons for their rapid growth in popularity. BSS have evolved technologically, transitioning from smart dock systems to smart bicycle systems, and it is not clear if the increased use of electronics in BSS results in a net environmental benefit. This article provides an evaluation of the impact of incorporating additional technology into BSS and uses that analysis as guidance for future BSS development. By comparing the impacts of a private bicycle, a smart dock BSS, and smart bike BSS using a life cycle assessment (LCA), this work reveals breakeven points and tradeoffs between the technologies. This study is also the first published empirical LCA of a smart bike known to the authors. In the production phase, smart bikes generate approximately three times the amount of greenhouse gas (GHG) emissions compared to the smart dock bikes per kilometer ridden over the lifetime, and when considering the endpoint categories of human health, ecosystem, and resources, smart bikes have approximately 2.7 times the environmental impact. The results suggest that shifting from smart dock to smart bike requires an increase in ridership by a factor of 1.8 to overcome the increased environmental impact based on the GHG emissions. We find that smart docks become preferable at a population density between 1,030 residents/km2 (in a bike friendly city) and 3,100 residents/km2 (in a city that is less likely to bike).

Social impact assessment (SIA) provides a methodology for defining, monitoring and employing measures to demonstrate the benefits and/or harms created for target communities through evidence of social outcomes and impacts. Although a recent increase in the number of applications is seen, SIA lacks consensus in its methodology, which increases ambiguity and complicates the generalization of any results obtained from individual studies. The objectives of this study are to investigate the methodology of SIA in order to define trends, state of the art, limitations, knowledge gaps, and to recommend future research directions. This study employs a systematic mapping to determine the methods available to perform SIA, and more importantly to identify a set of fundamental challenges faced by practitioners using SIA. Articles are searched through online databases, and are limited to the English language. A total of 81 articles published between 2009 and 2019 were selected, of which 49 included a case study application. A total of 12 fundamental challenges were identified, based upon the screened articles, which serve as a starting point for future research directions to further enhance the SIA methodology.

No abstract

Background Social life-cycle assessment (S-LCA) provides a framework to evaluate the social impacts of decisions made during the design phases of a product. Rooftop solar panels are considered an environmentally friendly renewable energy technology due to their ability to generate electricity without producing greenhouse gases while generating electricity. This study presents the application of a challenge-derived S-LCA framework to assess the social impacts of rooftop solar panels in the southeast region of the United States (U.S.) during the use and end-of-life phases. Methods The challenge-derived S-LCA framework was developed based on a set of challenges to performing social assessments. The challenges were identified through a systematic mapping process and verified using expert feedback. Additional feedback is gathered through users from mechanical engineering capstone design students. The case study application shown in this paper aims to identify the potential social impacts at a pre-implementation stage of the rooftop solar panel in residential applications. The framework follows the ISO 14040 LCA structure, and the analysis was performed based on impact indicators (Type-I framework) and performance reference points (PRP). Results The framework implements existing social impact assessment methodologies, and guides each of the assessment stages based on the type of analysis performed. The results highlight the workers as the stakeholder group with the highest social impacts. The results also highlight the need for regulation to make rooftop solar panels accessible to low-income community members. Conclusions An S-LCA framework to assess the social impacts of product systems and technologies is implemented to evaluate the potential social impacts of residential rooftop solar panels. The framework presented applies to product systems and technologies at a pre- or post-implementation state, and it aims to guide novice and expert users alike. Nonetheless, further research is still needed to improve the methodology presented, and additional case studies should be performed to test the applicability of the framework across a broad set of fields.