About 60% of plastic packaging in Sweden ends up in mixed municipal solid waste (MSW), which is incinerated with energy recovery. This status quo presents a missed opportunity to meet ambitious recycling targets. This study aims to provide a detailed characterization of plastic packaging in mixed MSW to assess its potential for recycling and its significance in improving the overall recycling rate. A case study involving a Swedish city was conducted wherein a sample of 5500 kg of mixed MSW from 920 households was characterized. From the 31% recycling rate, improvement of up to 59% can be achieved by diverting this misplaced plastic packaging into the existing recycling system. An additional 9% increase remains challenging to achieve due to the occurrence of non-recyclable attributes like black and multilayer packaging. The highlighted key enabler is the combination of correct household waste separation behavior and the establishment of mechanical sorting facilities to recover plastic waste from mixed MSW. These recycling potentials and associated challenges are discussed in the context of Sweden's ongoing efforts across the plastic packaging value chain. Furthermore, the importance of extended waste characterization is emphasized as a tool for identifying recycling potentials and monitoring the effectiveness of measures in enhancing circularity and resource-efficiency. 

Policy is decisive to stimulate biogas expansion; but policy-related factors may also inhibit the development. This study explores policy risks in the Swedish biogas sector and identifies strategies to mitigate these risks. The study is based on three workshops and a survey with participation of biogas stakeholders. The findings reveal that two major policy risks significantly impact the Swedish biogas sector: the ‘lack of long-term strategies’ and the ‘long and complicated permitting processes.’ ‘Limitations of permitted feedstocks’ and ‘limited system perspective—benefits of circular economy and sustainable food system’ are also among the most probable risks. More clearly defined roles for authorities at different administrative levels and the promotion of life cycle perspectives are critical to mitigate these risks. The research emphasizes that both EU and national governments play vital roles in reducing policy risks through predictable and long-term biogas strategies. Without these interventions, the potential of the Swedish biogas sector may remain underutilized.

Urban Water Infrastructure systems (UWI) are central to functioning cities. For securing a continuous and efficient supply of the systems services, continuous investment, maintenance, and renewal are needed. Neglecting maintenance and renewal can lead to recurrent breakdown problems as systems age, which makes it more and more difficult to secure efficient long-term supply. Globally, many cities struggle with aging water infrastructure, often due to competing funding priorities. Investment in maintenance and renewal is not prioritized. The problem primarily stems from the challenge of reaping the benefits of investments promptly. The long-term benefits gained from investing in the renewal of water infrastructure may be achievable in the long run, resulting in the oversight of such investments. This leads to a build-up of "renewal debt" for future generations to inherit. Addressing this issue is difficult due to various contributing factors and the complex nature of the systems. The study aims to contribute to an increased understanding of the long-term management challenges UWI, the development of improved maintenance and renewal strategies through the examination of water infrastructure management, and the assessment of the adequacy of the maintenance and renewal in a case study, the city of Linköping, Sweden. Employing a mixed methods approach, this study utilized both qualitative and quantitative methods, including interviews, workshops, and data analysis. The findings of the study provided insights into the current status of the water and sewerage networks in Linköping, highlighting the risks to ensuring reliable and sustainable water supply and discussing strategies for improving maintenance and renewal.

In Chapter 10, Shabb, McCormick, Anderberg and Mujkic investigate how Climate City Contracts (CCCs) are being developed in Europe and what it means for other parts of the world. CCCs are intended to be different from current strategies to tackle climate change because they are designed as part of a larger mission with many stakeholders, funding and growing momentum. CCCs are a mechanism to ensure that city-level work is not occurring in a vacuum but rather facilitates multi-level integration between cities, national agencies, and the European Union, but also collaboration across all stakeholders. The current focus of CCCs is mostly on the process rather than outcomes. Ambitious Climate Investment Plans, which encompass private sector efforts, are necessary to underpin the goals and activities outlined in CCCs.

Sweden aims to increase biogas production from anaerobic digestion (AD) from 2 to 7 TWh/year until 2030. This paper investigates the requirements, challenges and implications of such a development through qualitative and quantitative assessment of three scenarios. Seven key elements—national policies and policy instruments, regional policies and policy instruments, mobilization of feedstock, infrastructure for feedstock and gas, mobilization of actors, new production facilities, and stable and increasing demand—were defined for the scenario construction and were also used to structure the comparative analysis. Quantitatively, increasing the biogas production from 2 to 7 TWh is estimated to require up to 5 times larger digester volume and up to 12 times more AD plants, meanwhile producing 6 – 8 times more biofertilizers. While a centralized production structure would be more efficient, a decentralized structure with small biogas plants would facilitate the logistics of agricultural substrates and biofertilizers. New production capacity could be incentivized through new and increased production subsidies, as well as an increased demand for renewable energy. Regardless of how the goal is to be achieved, it will require collective efforts from both public and private actors to overcome the many challenges on the way.

The city's wire-based infrastructure systems (WBIS) are responsible for the delivery of electricity,telecommunications, sanitation, drainage, and district heating and are a necessity for sustainable modern urban life.Maintaining the functionality of these structures involves high costs and, brings disturbance to the local community and effectson the environment. One key reason for this is that the cables and pipes are placed under streets, making system parts easilyworn and their service lifetime reduced, and all maintenance and renewal rely on recurrent needs for excavation. In Sweden, asignificant part of wire-based infrastructure is already outdated and will need to be replaced in the coming decades. Thereplacement of these systems will entail massive costs as well as important traffic disruption and environmental disturbance.However, this challenge may also open a unique opportunity to introduce new, more sustainable technologies and managementpractices. The transformation of WBIS management for long-term sustainability and meeting maintenance and renewal needsdoes not have a comprehensive approach. However, a systemic approach may inform WBIS management. This approachconsiders both technical and non-technical aspects, as well as time-related factors. Nevertheless, there is limited systemicknowledge of how different factors influence current management practices. The aim of this study is to address this knowledgegap and contribute to the understanding of what factors influence the current practice of WBIS management. A case studyapproach is used to identify current management practices, the underlying factors that influence them, and their implicationsfor sustainability outcomes. The case study is based on both quantitative data on the local system and data from interviews andworkshops with local practitioners and other stakeholders. Linköping was selected as a case since it provided goodaccessibility to the water administration and relevant data for analyzing water infrastructure management strategies. It is asufficiently important city in Sweden to be able to identify challenges, which, to some extent, are common to all Swedish cities.By uncovering current practices and what is influencing Linköping, knowledge gaps and uncertainties related to sustainabilityconsequences were highlighted. The findings show that goals, priorities, and policies controlling management are shorttermed, and decisions on maintenance and renewal are often restricted to finding solutions to the most urgent issues.Sustainability transformation in the infrastructure area will not be possible through individual efforts without coordinatedtechnical, organizational, business, and regulatory changes.

The single-use function of plastic packaging generates a continuously increasing input to the waste management system leading to sustainability challenges. In response, several management strategies along the plastic value chain are proposed including improvements on product design, source-separation, mechanical and optical sorting, and further downstream material recycling. However, in some countries like Sweden, these strategies are often implemented in isolation without considering their combination effects on the performance of the entire plastic value chain. Moreover, the corresponding assessments of these strategies are often limited to material efficiency (i.e., recycling rate) thus overlooking the potential trade-offs with environmental performance. Hence, this study aims to assess the combination effects of different management strategies for plastic packaging in Sweden in terms of both material and environmental dimensions. Over 700 scenarios involving different combinations of management strategies were modeled and assessed through life cycle assessment. The results show that upstream strategies such us polymer restriction especially for food packaging (i.e., limiting to polyethylene terephthalate and polypropylene) lead to higher recycling rates and better environmental performance. In contrast, further downstream material recycling strategies show more apparent trade-offs, especially between recycling rates and environmental impacts related to toxicity. Recommendations for the combinations of management strategies for plastic packaging, which can increase recycling rates and reduce environmental impacts, are presented and discussed. 

Multi-utility tunnel (MUT) have received increasing attention as an alternative method for installing subsurface infrastructure for the distribution of electricity, telecommunications, water, sewage and district heating. MUTs are described as a potentially more sustainable technology than conventional open-cut excavation (OCE), especially if the entire life cycle of these cable and pipe networks is taken into account. Based on an extensive review of the academic literature, this article aims to identify and critically examine claims made about the pros and cons of using MUT for the placement of subsurface infrastructure. Identified claims are mapped, and their validity and applicability assessed. These claims are then analyzed from a sustainability perspective, based on the three sustainability dimensions and a life cycle perspective. The results show that a variety of advantages and disadvantages of using MUTs for subsurface infrastructure are highlighted by the articles, but several of these are without any empirical support. When some form of empirical support is presented, it usually comes from case-specific analyses of MUTs, and the applicability in other MUT projects is seldom discussed. Economic performance is the sustainability dimension that has received the most attention, while environmental performance has not been analyzed in the reviewed literature, which is a major limitation of the current knowledge. In summary, the knowledge about the sustainability performance of using MUTs for subsurface infrastructure is still limited and incoherent. In order to increase the knowledge, this article points out the importance of new case studies, in which the sustainability consequences of using MUTs for subsurface infrastructure are mapped and evaluated by combining both quantitative and qualitative assessment methods.

This paper compares and analyzes the relations between the biogas development and the national policy frameworks for biogas solutions in eight European countries. The policy frameworks are compared using a biogas policy model, comprising five dimensions: type of policy; administrative area; administrative level; targeted part of the value chain; and continuity and change over time. The studied countries show examples of both increasing and stagnating biogas production, all of which can be associated with changes in national policy frameworks. Many different policy tools?particularly economic instruments?have proven successful for stimulating biogas production, but changing a well-functioning framework risks impeding the development. Therefore, predictability and relevance for targeted actors are key in policymaking. Targeting specific parts of the value chain can however be required to integrate all the benefits of biogas solutions, such as agricultural methane emissions reduction. Moreover, it can be challenging to design policies and policy instruments that are both effective and sustainable over time, without needs for modifications or adjustments. Finally, biogas policies and policy instruments that are effective in one country would not necessarily lead to the same outcome in another country, as they are dependent on the broader context and policy and economic framework.

Contemporary environmental problems require a transition to renewable energy. Biogas is one alternative, which besides being renewable has many other benefits. For further expansion of biogas production, it seems necessary to develop new areas of biogas usage where biogas can replace fossil fuels. This article presents an analysis of the drivers for and barriers to increased biogas usage in three sectors where biogas usage is undeveloped in Sweden: manufacturing, road transport and shipping. Several of the identified drivers and barriers, such as unstable and short-term policies, lack of infrastructure, and contract requirements, have also been found in previous studies even though they may be slightly different depending on the context. A new driver observed in this study is that of intergenerational thinking in family-owned businesses. The study also reiterates the significant influence of policy in the form of subsidies, tax exemptions and regulations on the adoption and use of renewable energy in general and biogas specifically. The results suggest the need for future policymaking to be guided by long-term trajectories, which can be a relevant basis for adopters to make investments into biogas technologies.