Abstract

International audience; City systems, consisting of the various social and technical infrastructures required for urban areas to function, are facing major challenges in the coming decades as global urbanization and the pressure on resource efficiency and sustainability continue. Agent-based simulation and modelling techniques enable us to study these systems from various levels of abstraction looking at actors as well as system level perspectives, and are particularly suited to understand the dynamics of underlying structures and experiment with various scenarios and the effect of local decisions on emerging system properties. This special issue aims to showcase innovative use of agent-based modelling (ABM) and multi-agent system (MAS) approaches for effective decision support regarding urban innovations in fields linked with urban development and to explore and identify how researchers in different disciplines integrate their knowledge through agent models. We are inviting researchers from across a wide range of disciplines (including computer science, physics, engineering, economics, sociology and others) to submit papers to this special issue that exhibit state-of the art innovation in ABM/MAS applied to cities. This innovation may come in the form of computational, conceptual, analytical, participatory or epistemological advances for a range of aims and motivations associated with the challenge of combining competitiveness and sustainable urban development in city systems. Possible topics include, but are not limited to, the following:[...]

Abstract

Significance Carbon dioxide removal through the permanent sequestration of biogenic CO2 is a critical technique for climate change mitigation, but most bioenergy with carbon capture and sequestration (CCS) technologies are technically immature or commercially unavailable. In contrast, examples of CCS of biogenic CO2 resulting from fermentation emissions already exist at scale. Here, we evaluate low-cost, commercially ready sequestration opportunities for existing biorefineries in the United States. We find that existing and proposed financial incentives suggest a substantial near-term opportunity to catalyze the growth of CCS infrastructure, improve the impacts of conventional biofuels, support development of carbon-negative biofuels, and satisfy low-carbon fuel policies. Capture and permanent geologic sequestration of biogenic CO2 emissions may provide critical flexibility in ambitious climate change mitigation. However, most bioenergy with carbon capture and sequestration (BECCS) technologies are technically immature or commercially unavailable. Here, we evaluate low-cost, commercially ready CO2 capture opportunities for existing ethanol biorefineries in the United States. The analysis combines process engineering, spatial optimization, and lifecycle assessment to consider the technical, economic, and institutional feasibility of near-term carbon capture and sequestration (CCS). Our modeling framework evaluates least cost source–sink relationships and aggregation opportunities for pipeline transport, which can cost-effectively transport small CO2 volumes to suitable sequestration sites; 216 existing US biorefineries emit 45 Mt CO2 annually from fermentation, of which 60% could be captured and compressed for pipeline transport for under $25/tCO2. A sequestration credit, analogous to existing CCS tax credits, of $60/tCO2 could incent 30 Mt of sequestration and 6,900 km of pipeline infrastructure across the United States. Similarly, a carbon abatement credit, analogous to existing tradeable CO2 credits, of $90/tCO2 can incent 38 Mt of abatement. Aggregation of CO2 sources enables cost-effective long-distance pipeline transport to distant sequestration sites. Financial incentives under the low-carbon fuel standard in California and recent revisions to existing federal tax credits suggest a substantial near-term opportunity to permanently sequester biogenic CO2. This financial opportunity could catalyze the growth of carbon capture, transport, and sequestration; improve the lifecycle impacts of conventional biofuels; support development of carbon-negative fuels; and help fulfill the mandates of low-carbon fuel policies across the United States. Document type: Article

Abstract

The transport sector's dependence on fossil fuels is one of the biggest challenges in a shift towards a climate-neutral and sustainable society. This roadmap report aims to investigate how electric vehicle systems can contribute to a faster transition to sustainable passenger transport in Southeast Sweden, as well as to present a methodology for guidance of similar work for faster transitions in other regions and sectors. This work has been guided by a scientifically designed and proven Framework for Strategic Sustainable Development (FSSD). Specifically, answers are given to four research questions structured in relation to the four subsystems 'Politics and instruments', 'Users and markets', 'Vehicles and infrastructure' and 'Energy and materials': What could a sustainable vision for passenger transport in Southeast Sweden look like? What could be a milestone goal for 2030? What is the current reality in relation to the 2030 goal and the vision? How could the gap between the present, 2030 and the vision be bridged? The report's results show that today's focus on fossil independence and measures against climate change must be broadened to cover the whole sustainability challengeso that other sustainability issues are addressed and so that solutions to some of the sustainability issues do not create new ones. The report also clarifies that it is necessary, practically possible and economically advantageous for Southeast Sweden to make a faster sustainability transition of passenger transportthan what has been proposed in previous studies and investigations. It is also likely that the same applies to the entire transport system and for the whole of Sweden and the world. Even geopolitical benefits are likely. A global transition to transport and energy systems based on energy from widely available flow resources like sun and wind instead of the limited fossil fuels would likely reduce the conflicts risks in the world.Restricted cobalt, lithium and platinum resources that battery and fuel cell cars depend on, and other metals needed for solar cells and wind turbines can, however, give rise to similar conflict risks. This roadmap report's recommendations on reduced transport needs and car dependency and its focus on resource efficiency counteract these conflict risks by striking against underlying resource-driving mechanisms. Should this roadmap be translated into practical policies, the forthcoming transition would therefore likely be made considerably more 'future-proof'. GreenCharge Southe

Abstract

The urban and rural energy systems are undergoing modernization. This modernization is motivated by the need to increase sustainability in both systems. Some characteristics of this modernization include electrification of industries, transports, and heating and cooling loads. Additionally, there has been an increase in building-applied photovoltaic (PV) systems, and in the flexibility of customer loads. This thesis aims to progress the knowledge regarding the electric power production and consumption in the future urban and rural energy systems. In total, three models were developed and applied to case studies: a spatial electric vehicle (EV) charging model, a residential load forecasting model, and a clear-sky index (CSI) generative model. The results of the EV spatial model showed that there is an aggregation effect for the charging of the EVs. If all EVs charge opportunistically upon arrival using 3.7 kW, at most 19% of the EVs in a large area will charge simultaneously. Delaying the charging to after 22:00 will result in a significant increase in the simultaneity factor — to 59%. Two forecasting models were compared for the residential load. Both models achieved a root mean square error (RMSE) smaller than 4%. One model had a slightly sharper forecast than the other model — by 2.6% — and a variable prediction interval (PI) which decreased at night. As regards the spatiotemporal matching between PV power production and EV charging in rural and urban areas, the results showed that there were no correlations between the building type in each part of the city and the temporal matching. Both residential and workplace areas had similar temporal matching. This is because of the orientations of the roofs in the cities and the sizes of the parking lots. Considering the impacts of EV charging on the distribution grid of a Swedish municipality (Herrljunga), it is shown that 3.7 kW chargers will result in at most a 1% decrease in the voltage of the grid. No under-voltages were witnessed. In conclusion, the urban and rural energy systems can withstand the penetration of PV and EVs in the nearby coming years. Extreme scenarios might, however, require increasing the flexibility or performing upgrades to the systems.  

Abstract

Today humankind is facing numerous sustainability challenges that require us to question CO2 intensive practices like those present in the transport and energy sector. To meet those challenges, many countries have adopted ambitious climate targets. Achieving such targets requires an understanding of the wider socio-technical context of transitions. The aim of this licentiate thesis is therefore to analyse such socio-technical transitions towards low-emission futures enabled by the electrification of passenger cars and high voltage grid development. A combination of different transitions theories (for ex. Multi-level perspective and Technological innovation systems) and institutional theory has been used. To reach the aim paper I analyses the climate impacts of electric vehicles (EVs) and policy measures to achieve a breakthrough scenario for EVs. The results show that a mixture of short and long term policies are needed that take into account the technology development stage and behavioural aspects of EV adopters. Paper II addresses the need to include the high voltage transmission grid and its planning procedures as a central part of debates on transitions. Therefore the opportunities, challenges and reasons for conflict in the established regime are studied. The results show that in order to achieve a sustainable grid development regime, it is necessary to spend time on achieving legitimacy and social sustainability. The third paper uses semi-structured expert interviews and focuses on innovation dynamics for EV adoption. By focusing on dynamics instead of single policy measures, it is possible to grasp interactions within a niche, but also in between a niche, regime and landscape. The results show that strong initial technology legitimacy was needed to start substantial innovation dynamics. This could be further strengthened with a strong and broad coalition of actors. Both those factors led, if present, to an improved variety and match of policy instruments. As such this thesis has shown that transitions are not just about technology or policy instruments as such but about the dynamics and processes needed to enable them. This can be relevant in other transitions that otherwise may underestimate the importance of these components. "p"QC 20170512"/p" Norstr

Abstract

Biogas is largely utilised as vehicle fuel in public bus transport in Sweden today. This study investigates opportunities and barriers for continued domestic use and production of biogas, in relation to the ongoing electrification of public bus transport. The analysis is based on interviews with actors in public transport and the biogas sector, experts on biogas systems, and representatives for alternative user segments. Three regions were chosen as case-studies for investigations of prospects in public transport, i.e. Stockholm, Västra Götaland and Skåne, though alternative uses were studied from a national perspective. In addition to public transport, considered uses include road transport, sea transport, industries, and electricity and heat production. The study identifies a broad agreement among stakeholders that renewable resources should be implemented where they provide most benefits from a system perspective. Therefore, electric public buses are valued in urban environments, while biogas solutions are found suitable for regional routes. Biogas is further viewed as environmentally beneficial in all user segments except continuous electricity and heat production, where it largely would replace renewable rather than fossil sources. Regarding costs and competitiveness, probable future uses are identified within light and heavy-duty road transport, and in consumer-oriented industries, i.e. the food industry. Economic support in policy instruments is further considered essential for continuous development of the Swedish biogas sector, though current influential instruments, e.g. the tax exemption, are described as short-term and unpredictable. The willingness to pay for the collected societal benefits of biogas further decrease in transitions from public to private consumers, and as biogas solutions simultaneously are linked with limited or uncertain competitiveness in these sectors, risks prevail that such transitions could imply stagnations and declines in biogas use and production, given today’s situation. Idag används biogas till stor del som drivmedel för bussar inom kollektivtrafik i Sverige. Denna studie undersöker möjligheter och hinder för en fortsatt nationell användning och produktion av biogas, i samband med att bussar inom kollektivtrafiken nu elektrifieras. Analysen är baserad på intervjuer med aktörer inom kollektivtrafiken och biogassektorn, sakkunniga inom biogas, och alternativa användare av biogas. Tre regioner, Stockholm, Västra Götaland och Skåne, valdes som fallstudier för analys av möjligheter för fortsatt användning inom kollektivtrafiken. Alternativa användningar studerades istället ur ett nationellt perspektiv, och inkluderade vägtransporter, sjöfart, industri och el- och värmeproduktion. Studien visar att det råder enighet mellan intervjupersoner att förnybara resurser över lag ska användas där de medför störst samhällsnytta sett till samhället i stort. Inom kollektivtrafiken beskrivs elbussar därför som fördelaktiga i stadsmiljöer, medan biogas ses som lämpligt i regional trafik. Biogas framställs dessutom som miljömässigt fördelaktigt i alla alternativa användningsområden utom kontinuerlig el- och värmeproduktion, eftersom då främst förnybara och inte fossila resurser ersätts. Med hänsyn till kostnader och konkurrenskraft ses lätta och tunga transporter tillsammans med kundnära industrier, t.ex. livsmedelsindustrin, som troliga framtida användningsområden för biogas. Ekonomiskt stöd från styrmedel bedöms vara nödvändigt för en fortsatt utveckling av biogassektorn i Sverige, även om dagens styrmedel, t.ex. skattebefrielsen, beskrivs som kortsiktiga och oförutsägbara. Betalningsviljan för biogasens samlade samhällsnyttor minskar också vid en övergång från offentliga till privata kunder. Eftersom biogas därtill har en begränsad eller osäker konkurrenskraft jämtemot andra alternativ i de privata segmenten, identifierar denna studie risker för stagnation eller nedgång i användning och produktion av biogas vid en eventuell utfasning från den offentliga sektorn, givet dagens situation.

Abstract

The Swedish transportation sector needs to undergo major changes in order to achieve the established goals for climate and environment. The largest change is the replacement of fossil-fuelled vehicles to vehicles propelled by renewable energy sources, such as biofuels and electricity. To account for an increase in local electric power consumption, the electric power infrastructure of Sweden needs to adapt through expansion and reconstruction of the electric power grid. However, changes in infrastructure are usually expensive. It is therefore suitable to also examine alternative solutions, which could potentially be more cost efficient. One of these solutions are vehicle-to-grid (V2G), where electric vehicles acts as local electric power control and provides auxiliary services to the electric power grid. This thesis is a case study of a part of a low-voltage electric power grid on Gotland, with the goal of analysing the potential of V2G in the investigated area. The study focused on utilizing V2G for balancing electric power consumption and generation, and for adjusting voltage levels. Simulations of the area were executed in PSS®E for three different cases; one high-load case, low-load case and average-load case. It was found that by utilizing V2G a ramp up of electric power during mornings was delayed by approximately one hour, making the electric power grid potentially more compatible with photovoltaics (PV). However, the overall effects from V2G was fairly low. This outcome can partly be explained by the assumptions made in the report, and also due to some odd behaviour of the system model. 

Abstract

It has been argued that for the management of complex issues such as sustainability, which transcend traditional policy sectors and require coordination between several different interests and actors, policymaking depends upon collaboration and integration processes between different sectors and tiers of government. The overall aim of this thesis is therefore to study how and why (or why not) policy integration processes are being developed in regional policymaking and what this means for the achievement of sustainable transport. The thesis consists of two separate qualitative case studies of policymaking in two Swedish regions, one representing a least likely case and the other a most likely case of policy integration. The focus has been on the organizational actors involved in policymaking processes for the regional transport system. For the general discussion the theoretical framework of policy integration, complemented by the analytical concepts of policy logics, organizational identities and boundary object are used. The findings are presented in four articles. An overall conclusion is that policy integration processes do not necessarily result in policy for sustainable transport. If policy integration becomes a goal in itself and the same as joint policy, it risks neglecting sustainable values and becoming the smallest common denominator that a number of actors can agree on. For developing sustainable transport solutions, collaboration for the coordination of policy may be beneficial, but the aim of such processes should not be joint policy. För att beslut och riktlinjer ska kunna utformas så att de leder till lösningar av komplexa frågor, såsom hållbar utveckling, anses de behöva hanteras i samverkan mellan flertalet berörda sektorer och beslutsfattande nivåer. Det är dessa samverkansprocesser, beskrivna som integration under policy processer, som den här avhandlingen analyserar. Syftet är att studera om och hur integrerade regionala policyprocesser förekommer, hur de utvecklas samt deras betydelse för att åstadkomma ett hållbarare transportsystem. Detta undersöks genom kvalitativa fallstudier av två olika svenska regioner som representerar ett minst och ett mest troligt fall av integration av policy. Fallstudierna görs i regionerna Stockholms län och Västra Götalands län. Dessa två fall representerar dessutom två helt olika typer av regionala organisationer, vilket gör att de utgör underlag till, inte bara en diskussion om hållbara transporter, utan också om utvecklingen av den svenska regionala förvaltningsnivån. För analys används teori kring integration av policy och tre huvudsakliga analytiska begreppsansatser: policylogiker, organisationsidentiteter och gränsobjekt. Resultaten presenteras i fyra separata artiklar och dessa diskuteras tillsammans i den inledande kappan. I studien konstateras att integration av policysektorer och förvaltningsnivåer inte nödvändigtvis leder till transportlösningar som är mer hållbara. Beslut om en gemensam policy över sektorer och nivåer riskerar bli urvattnad eftersom det är många aktörer som ska komma överens. Samverkan för att samordna olika mål och intressen visar sig i huvudsak vara viktigt för att styra mot ett hållbart transportsystem, men det innebär inte att gemensam policy bör vara målet. Därutöver belyser studien hur olika organisationsformer på regional nivå påverkar regionala beslutsprocesser och hanteringen av hållbar transportutveckling.

Abstract

This paper presents a new practical approach to optimally allocate charging stations in large-scale transportation networks for electric vehicles (EVs). The problem is of particular importance to meet the charging demand of the growing fleet of alternative fuel vehicles. Considering the limited driving range of EVs, there is need to supply EV owners with accessible charging stations to reduce their range anxiety. The aim of the Route Node Coverage (RNC) problem, which is considered in the current paper, is to find the minimum number of charging stations, and their locations in order to cover the most probable routes in a transportation network. We propose an iterative approximation technique for RNC, where the associated Integer Problem (IP) is solved by exploiting a probabilistic random walk route selection, and thereby taking advantage of the numerical stability and efficiency of the standard IP software packages. Furthermore, our iterative RNC optimization procedure is both pertinent and straightforward to implement in computer coding and the design technique is therefore highly applicable. The proposed optimization technique is applied on the Sioux-Falls test transportation network, and in a large-scale case study covering the southern part of Sweden, where the focus is on reaching the maximum coverage with a minimum number of charging stations. The results are promising and show that the flexibility, smart route selection, and numerical efficiency of the proposed design technique, can pick out strategic locations for charging stations from thousands of possible locations w ithout numerical difficulties. ©2019 Hie Authors. Published by Elsevier B.V. "p"open acce