| 1. |
- Liljenström, Hans, et al.
(author)
-
Scoping Report on Socio-Economic and Land Use Dynamics in the Stockholm-Mälar Region
- 2014
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Reports (other academic/artistic)abstract
- This scoping report for the COMPLEX work package 4 (WP4) on Socio-Economic and Land Use Dynamics in the Stockholm-Mälar Region has several objectives. The first is to present and outline the state-of-the-art, including a literature review, with regard to complex pathways to a low carbon society, with special relevance to the Stockholm-Mälar region. It will do so in a larger context of complex socio-natural systems, with an emphasis on a green economy, bioen-ergy and land use, as well as on societal transformation and behavioural change. Another objec-tive is to inform primarily our partners in COMPLEX, but also others who might be interested, including stakeholders in our study region. Perhaps the most important objective with this re-port is to provide a basis for the collaborative work within our work package, and with our col-leagues elsewhere. In this second revised version of the report, we have extended some parts, and shortened others, depending on suggestions and interesting new information. A part of this new information has come from a stakeholder workshop held in Sigtuna in early 2014, which to a great extent could contribute to a more elaborate analysis of stakeholder and policy maker positions. In addition, there is now a more extensive description of relevant land use modelling. The illustrations included in this report are extracted from scientific articles and other material that we are referring to. Their origin is explicitly cited but no copyright authorization has been requested, while this report is intended primarily for internal spread and use within the COM-PLEX consortium and its networks.
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| 2. |
- Englund, Oskar, 1982, et al.
(author)
-
Large-scale deployment of grass in crop rotations as a multifunctional climate mitigation strategy
- 2023
-
In: GCB Bioenergy. - : Wiley. - 1757-1707 .- 1757-1693. ; 15:2, s. 166-184
-
Journal article (peer-reviewed)abstract
- The agriculture sector can contribute to climate change mitigation by reducing its own greenhouse gas (GHG) emissions, sequestering carbon in vegetation and soils, and providing biomass to substitute for fossil fuels and other GHG-intensive products. The sector also needs to address water, soil, and biodiversity impacts caused by historic and current practices. Emerging EU policies create incentives for cultivation of perennial plants that provide biomass along with environmental benefits. One such option, common in northern Europe, is to include grass in rotations with annual crops to provide biomass while remediating soil organic carbon (SOC) losses and other environmental impacts. Here, we apply a spatially explicit model on >81,000 sub-watersheds in EU27 + UK (Europe) to explore the effects of widespread deployment of such systems. Based on current accumulated SOC losses in individual sub-watersheds, the model identifies and quantifies suitable areas for increased grass cultivation and corresponding biomass- and protein supply, SOC sequestration, and reductions in nitrogen emissions to water as well as wind and water erosion. The model also provides information about possible flood mitigation. The results indicate a substantial climate mitigation potential, with combined annual GHG savings from soil-carbon sequestration and displacement of natural gas with biogas from grass-based biorefineries, equivalent to 13%–48% of current GHG emissions from agriculture in Europe. The environmental co-benefits are also notable, in some cases exceeding the estimated mitigation needs. Yield increases for annual crops in modified rotations mitigate the displacement effect of increasing grass cultivation. If the grass is used as feedstock in lieu of annual crops, the displacement effect can even be negative, that is, a reduced need for annual crop production elsewhere. Incentivizing widespread deployment will require supportive policy measures as well as new uses of grass biomass, for example, as feedstock for green biorefineries producing protein concentrate, biofuels, and other bio-based products.
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| 3. |
- Thomas, Jean-Baptiste, et al.
(author)
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A comparative environmental life cycle assessment of hatchery, cultivation, and preservation of the kelp Saccharina latissima
- 2021
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In: Ices Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 78:1, s. 451-467
-
Journal article (peer-reviewed)abstract
- Seaweed cultivation and processing industries could contribute to sustainable blue growth and the European bioeconomy. This article contributes a case study evaluation of environmental sustainability of preserved brown seaweed Saccharina latissima by means of environmental life cycle assessment of a pilot facility in Sweden. The study accounts for nutrient bioremediation and carbon capture and includes two alternative hatchery processes, a 2-ha longline cultivation, and four alternative preservation methods (hang-drying outdoors, heated air-cabinet drying, ensiling, and freezing). The study found that as a result of carbon capture and nitrogen and phosphorus uptake (bioremediation) by seaweed, more CO2 and PO4 equivalents are (temporarily) absorbed than emitted by the supply chain. The extent of emissions is most affected by preservation methods undertaken. Impact profiles of the supply chain show that the greatest impact shares result from freezing and air-cabinet drying, both the two most energy-intensive processes, followed by the cultivation infrastructure, highlighting strategic optimization opportunities. Hatchery processes, harvesting, and the low-energy ensilage and hang-drying outdoors were found to have relatively small impact shares. These findings presage the environmentally friendliness of seaweed-based products by documenting their potential to mitigate eutrophication and climate change, even when taking a life cycle perspective.
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| 4. |
- Ekener, Elisabeth, 1963-, et al.
(author)
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Developing Life Cycle Sustainability Assessment methodology by applying values-based sustainability weighting - Tested on biomass based and fossil transportation fuels
- 2018
-
In: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526 .- 1879-1786. ; 181, s. 337-351
-
Journal article (peer-reviewed)abstract
- The production and use of transportation fuels can lead to sustainability impacts. Assessing them simultaneously in a holistic way is a challenge. This paper examines methodology for assessing the sustainability performance of products in a more integrated way, including a broad range of social impacts. Life Cycle Sustainability Assessment (LCSA) methodology is applied for this assessment. LSCA often constitutes of the integration of results from social LCA (S-LCA), environmental life cycle assessment (E-LCA) and life cycle costing (LCC). In this study, an S-LCA from an earlier project is extended with a positive social aspect, as well as refined and detailed. E-LCA and LCC results are built from LCA database and literature. Multi Criteria Decision Analysis (MCDA) methodology is applied to integrate the results from the three different assessments into an LCSA. The weighting of key sustainability dimensions in the MCDA is performed in different ways, where the sustainability dimensions are prioritized differently priority based on the assumed values of different stakeholder profiles (Egalitarian, Hierarchist, and Individualist). The developed methodology is tested on selected biomass based and fossil transportation fuels - ethanol produced from Brazilian sugarcane and US corn/maize, and petrol produced from Russian and Nigerian crude oils, where it delineates differences in sustainability performance between products assessed. The outcome in terms of relative ranking of the transportation fuel chains based on sustain ability performance differs when applying different decision-maker profiles. This result highlights and supports views that there is no one single answer regarding which of the alternatives that is most sustainable. Rather, it depends strongly upon the worldview and values held by the decision maker. A key conclusion is that sustainability assessments should pay more attention to potential differences in underlying values held by key stakeholders in relevant societal contexts. The LCSA methodology still faces challenges regarding results integration but MCDA in combination with stakeholder profiles appears to be a useful approach to build on further.
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| 5. |
- Hörteborn, Axel, 1986, et al.
(author)
-
Economic incentives and technological limitations govern environmental impact of LNG feeder vessels
- 2023
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In: Journal of Cleaner Production. - : Elsevier Ltd. - 0959-6526 .- 1879-1786. ; 429
-
Journal article (peer-reviewed)abstract
- In the transition to sustainable shipping, Liquified Natural Gas (LNG), is proposed to play a role, reducing emissions of sulphur and nitrogen oxides, and particulate matter. However, LNG is a fossil fuel and there is an ongoing discussion regarding the extent of methane slip from ships operating on LNG, challenging the assumptions of LNG as a sustainable solution. Here we show another aspect to consider in the environmental assessment of shipping; LNG feeder vessels may spend as much as 25% of their time at sea just running the ship to ensure the pressure in the tanks are not exceeded, i.e., run time not directly attributed to the shipment of gas from one port or ship, to another. In other words, the economic incentives are currently allowing for roughly 32% increase of the ships’ operational emissions and discharges and increased navigational risks. Most coastal areas are heavily affected by anthropogenic activities and e.g., in the Baltic Sea there is consensus among the HELCOM member states that the input of nutrient and hazardous substances must be reduced. Even if the LNG feeder vessels are currently few, the possibility to reduce their environmental impact by 32% should be an attractive opportunity for future policy measures and investigation of technological solutions of the problem.
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| 6. |
- Shahroozi, Zahra, 1992-
(author)
-
Survivability control using data-driven approaches and reliability analysis for wave energy converters
- 2024
-
Doctoral thesis (other academic/artistic)abstract
- Wave energy, with five times the energy density of wind and ten times the power density of solar, offers a compelling carbon-free electricity solution. Despite its advantages, ongoing debates surround the reliability and economic feasibility of wave energy converters (WECs). To address these challenges, this doctoral thesis is divided into four integral parts, focusing on optimizing the prediction horizon for power maximization, analyzing extreme waves' impact on system dynamics, ensuring reliability, and enhancing survivability in WECs.Part I emphasizes the critical importance of the prediction horizon for maximal power absorption in wave energy conversion. Using generic body shapes and modes, it explores the effect of dissipative losses, noise, filtering, amplitude constraints, and real-world wave parameters on the prediction horizon. Findings suggest achieving optimal power output may be possible with a relatively short prediction horizon, challenging traditional assumptions.Part II shifts focus to WEC system dynamics, analyzing extreme load scenarios. Based on a 1:30 scaled wave tank experiment, it establishes a robust experimental foundation, extending into numerical assessment of the WEC. Results underscore the importance of damping to alleviate peak forces. Investigating various wave representations highlights conservative characteristics of irregular waves, crucial for WEC design in extreme sea conditions.Part III explores the computational intricacies of environmental design load cases and fatigue analyses for critical mechanical components of the WEC. The analysis is conducted for hourly sea state damage and equivalent two-million-cycle loads. Finally, a comparison of safety factors between the ultimate limit state and fatigue limit state unfolds, illustrating the predominant influence of the ultimate limit state on point-absorber WEC design.Part IV, centers on elevating survivability strategies for WECs in extreme wave conditions. Three distinct controller system approaches leverage neural networks to predict and minimize the line force. Distinct variations emerge in each approach, spanning from rapid detection of optimal damping to integrating advanced neural network architectures into the control system with feedback. The incorporation of a controller system, refined through experimental data, showcases decreases in the line force, providing a practical mechanism for real-time force alleviation.This thesis aims to contribute uniquely to the goal of advancing wave energy conversion technology through extensive exploration.
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| 7. |
- Vikström, Hanna, 1985-, et al.
(author)
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Lithium availability and future production outlooks
- 2013
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In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 110:10, s. 252-266
-
Journal article (peer-reviewed)abstract
- Lithium is a highly interesting metal, in part due to the increasing interest in lithium-ion batteries. Several recent studies have used different methods to estimate whether the lithium production can meet an increasing demand, especially from the transport sector, where lithium-ion batteries are the most likely technology for electric cars. The reserve and resource estimates of lithium vary greatly between different studies and the question whether the annual production rates of lithium can meet a growing demand is seldom adequately explained. This study presents a review and compilation of recent estimates of quantities of lithium available for exploitation and discusses the uncertainty and differences between these estimates. Also, mathematical curve fitting models are used to estimate possible future annual production rates. This estimation of possible production rates are compared to a potential increased demand of lithium if the International Energy Agency’s Blue Map Scenarios are fulfilled regarding electrification of the car fleet. We find that the availability of lithium could in fact be a problem for fulfilling this scenario if lithium-ion batteries are to be used. This indicates that other battery technologies might have to be implemented for enabling an electrification of road transports.
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| 8. |
- Englund, Oskar, 1982
(author)
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On Sustainability of Biomass for Energy and the Governance Thereof
- 2016
-
Doctoral thesis (other academic/artistic)abstract
- Due to concerns about climate change, energy security, and resource scarcity, non- renewable resources are increasingly being displaced by biomass. As with most human activities, the production of biobased products can be associated with negative impacts. Primarily, this relates to the biomass supply systems, i.e., agriculture and forestry, which currently are major causes of biodiversity loss and degradation of ecosystem services. Developing sustainable production systems when transitioning from non-renewable resources to biomass is imperative. This thesis aims to clarify the meaning of sustainability in the context of biomass for bioenergy, and contribute to our understanding of how different forms of governance can promote sustainably sourced biomass for bioenergy. The thesis is based on five appended papers: Paper I analyses to what extent, where, and under what conditions oil palm for biodiesel in Brazil can be produced profitably, and what risks and opportunities that can be associated with introducing large-scale oil palm production in Brazil. Paper II lays the foundation for understanding how new biomass production can be introduced into landscapes while supporting rather than compromising the ability of the landscape to supply other ecosystem services. Paper III describes different forms of governance and shows how these can play different roles in promoting sustainable bioenergy in different countries. Paper IV focuses on how short rotation coppice production systems are affected by EU policy and how different governance forms can assist in adapting production systems to conform to the corresponding sustainability requirements. Finally, Paper V assesses how sustainability certification (private governance) addresses biodiversity conservation and contributes to our understanding of possible improvements.
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| 9. |
- Svensson, Olle, 1967-
(author)
-
Experimental results from the Lysekil Wave Power Research Site
- 2012
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Doctoral thesis (other academic/artistic)abstract
- This thesis presents how experimental results, from wave power research performed offshore at the Lysekil research site, were obtained. The data were used to verify theoretical models as well as evaluate the feasibility of wave power as a future sustainable energy source.The first experiments carried out at the research site was the measurement of the force in a line where one end was connected to a buoy with a diameter of 3 m and the other end to a set of springs with limited stroke length. The system is exposed to high peak forces compared to average forces. The maximum measured force in the line, when the buoy motion is limited by a stiff stopper rope is ten times the average force in that particular sea state.The experiment performed on the first wave energy converter tested at the Lysekil Research Site is described. The infrastructure of the site is presented where the central connection point is the measuring station. The key finding is that it is possible to transform the motions of ocean waves into electrical energy and distribute it to land.Many wave energy converters must be interconnected if large amounts of energy are to be harvested from the waves. The first submerged substation intended for aggregation of energy from wave power converters is described, with focus on the measurement and control system placed inside the substation. During this experiment period the generators were equipped with many different sensors; these measurements are explained in the thesis.The system that aggregates power from the studied wave energy converter is regularly exposed to peak power of up to 20 times the maximum average output from the converter.Vertical and horizontal movement of the buoy has been measured in different ways. The result is that the vertical displacement of the buoy can be measured with a simple accelerometer circuit but it is much more complicated to measure the horizontal displacement. A special method for measuring the horizontal displacement has been implemented by measuring the strain in the enclosure and the force in the line.
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| 10. |
- Cowie, A. L., et al.
(author)
-
Applying a science-based systems perspective to dispel misconceptions about climate effects of forest bioenergy
- 2021
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In: Global Change Biology Bioenergy. - : John Wiley and Sons Inc. - 1757-1693 .- 1757-1707. ; 13:8, s. 1210-1231
-
Journal article (peer-reviewed)abstract
- The scientific literature contains contrasting findings about the climate effects of forest bioenergy, partly due to the wide diversity of bioenergy systems and associated contexts, but also due to differences in assessment methods. The climate effects of bioenergy must be accurately assessed to inform policy-making, but the complexity of bioenergy systems and associated land, industry and energy systems raises challenges for assessment. We examine misconceptions about climate effects of forest bioenergy and discuss important considerations in assessing these effects and devising measures to incentivize sustainable bioenergy as a component of climate policy. The temporal and spatial system boundary and the reference (counterfactual) scenarios are key methodology choices that strongly influence results. Focussing on carbon balances of individual forest stands and comparing emissions at the point of combustion neglect system-level interactions that influence the climate effects of forest bioenergy. We highlight the need for a systems approach, in assessing options and developing policy for forest bioenergy that: (1) considers the whole life cycle of bioenergy systems, including effects of the associated forest management and harvesting on landscape carbon balances; (2) identifies how forest bioenergy can best be deployed to support energy system transformation required to achieve climate goals; and (3) incentivizes those forest bioenergy systems that augment the mitigation value of the forest sector as a whole. Emphasis on short-term emissions reduction targets can lead to decisions that make medium- to long-term climate goals more difficult to achieve. The most important climate change mitigation measure is the transformation of energy, industry and transport systems so that fossil carbon remains underground. Narrow perspectives obscure the significant role that bioenergy can play by displacing fossil fuels now, and supporting energy system transition. Greater transparency and consistency is needed in greenhouse gas reporting and accounting related to bioenergy.
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| 11. |
- Habibi, Shiva, 1978, et al.
(author)
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Comparison of free-floating car-sharing services in cities
- 2017
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In: ECEEE Summer Study, 29 May - 3 June, 2017. - 2001-7960. - 9789198387810 ; 2017
-
Conference paper (peer-reviewed)abstract
- In recent years, free-floating car sharing services (FFCS) have been offered by many organizations as a more flexible option compared to traditional car sharing. FFCS allows users to pick up and return cars anywhere within a specified area of a city. FFCS can provide a high degree of utilization of vehicles and less usage of infrastructure in the form of parking lots and roads and thus has the potential to increase the efficiency of the transport sector. However, there is also a concern that these compete with other efficient modes of transport such as cycling and public transport. The aim of this paper is to better understand how, when and where the vehicles are utilized through logged data of the vehicles’ movements. We have access to data collected on FFCS services in 22 cities in Europe and North America which allows us to compare the usage pattern in different cities and examine whether or not there are similar trends. In this paper, we use the collected data to compare the different cities based on utilization rate, length of trip and time of day that the trip is made. We find that the vehicle utilization rates differ between cities with Madrid and Hamburg having some of the highest utilization levels for the FFCS vehicles. The results form a first step of a better understanding on how these services are being used and can provide valuable input to local policy makers as well as future studies such as simulation models.
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| 12. |
- Agrell, Erik, 1965
(author)
-
Kryptovalutor – energiförbrukning och miljöeffekter
- 2023
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In: En samhällsvetenskaplig introduktion till bitcoin och kryptovalutor.
-
Book chapter (other academic/artistic)abstract
- Detta kapitel fokuserar på bitcoins elförbrukning och även, i ett bredare perspektiv, annan miljöpåverkan. Efter en kort inledning i avsnitt 4.1 redovisas i avsnitt 4.2 några försök att uppskatta hur stor elförbrukningen egentligen är, och vilka källor till osäkerhet som finns i sådana uppskattningar. Motsvarande uppskattning av klimatskadliga utsläpp redovisas i avsnitt 4.3. Siffrorna sätts i perspektiv med några jämförelser i avsnitt 4.4. Utvecklingen över tid illustreras i avsnitt 4.5 och därmed kopplingen till bitcoinpriset. Miljöfrågan breddas till ett livscykelperspektiv i avsnitt 4.6, där produktion och skrotning av den specialtillverkade elektronik som används i bitcoinfabrikerna diskuteras. I avsnitt 4.7 ställs sedan den naturliga frågan: Vad finns det för alternativ? Kapitlet avslutas med några övergripande reflektioner i avsnitt 4.8.
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| 13. |
- Nordelöf, Anders, 1975, et al.
(author)
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A scalable life cycle inventory of an electrical automotive traction machine—part I: design and composition
- 2018
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In: International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 1614-7502 .- 0948-3349. ; 24:1, s. 55-69
-
Journal article (peer-reviewed)abstract
- Purpose: A scalable life cycle inventory (LCI) model of a permanent magnet electrical machine, containing both design and production data, has been established. The purpose is to contribute with new and easy-to-use data for LCA of electric vehicles by providing a scalable mass estimation and manufacturing inventory for a typical electrical automotive traction machine. The aim of this article (part I of two publications) is to present the machine design, the model structure, and an evaluation of the models’ mass estimations. Methods: Data for design and production of electrical machines has been compiled from books, scientific papers, benchmarking literature, expert interviews, various specifications, factory records, and a factory site visit. For the design part, one small and one large reference machine were constructed in a software tool, which linked the machines’ maximum ability to deliver torque to the mass of its electromagnetically active parts. Additional data for remaining parts was then gathered separately to make the design complete. The two datasets were combined into one model, which calculates the mass of all motor subparts from an input of maximum power and torque. The range of the model is 20–200 kW and 48–477 Nm. The validity of the model was evaluated through comparison with seven permanent magnet electrical traction machines from established brands. Results and discussion: The LCI model was successfully implemented to calculate the mass content of 20 different materials in the motor. The models’ mass estimations deviate up to 21% from the examples of real motors, which still falls within expectations for a good result, considering a noticeable variability in design, even for the same machine type and similar requirements. The model results form a rough and reasonable median in comparison to the pattern created by all data points. Also, the reference motors were assessed for performance, showing that the electromagnetic efficiency reaches 96–97%. Conclusions: The LCI model relies on thorough design data collection and fundamental electromagnetic theory. The selected design has a high efficiency, and the motor is suitable for electric propulsion of vehicles. Furthermore, the LCI model generates representative mass estimations when compared with recently published data for electrical traction machines. Hence, for permanent magnet-type machines, the LCI model may be used as a generic component estimation for LCA of electric vehicles, when specific data is lacking.
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| 14. |
- Nordelöf, Anders, 1975, et al.
(author)
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A scalable life cycle inventory of an electrical automotive traction machine—part II: manufacturing processes
- 2018
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In: International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 1614-7502 .- 0948-3349. ; 23:2, s. 295-313
-
Journal article (peer-reviewed)abstract
- Purpose: A scalable life cycle inventory (LCI) model of a permanent magnet electrical machine, containing both design and production data, has been established. The purpose is to contribute with new and easy to use data for life cycle assessment (LCA) of electric vehicles by providing a scalable mass estimation and manufacturing inventory for a typical electrical automotive traction machine. The aim of this article (part II of two publications) is to present the manufacturing data with associated collection procedures, from material constituents to complete motor. Another objective is to explain the gate-to-gate system boundaries and the principles for linking the LCI model upstream, to database data, in order to create a full cradle-to-gate dataset. Methods: Data for design and production of electrical machines has been compiled from books, scientific papers, benchmarking literature, expert interviews, various specifications, factory records, and a factory site visit. For the manufacturing part, new primary data was collected directly from industry, with a motor factory and a steel mill in Sweden as main contributors, and from technical literature. Other LCA publications were used, if presented in sufficient detail to be disaggregated and revised, to match the gaps of the model. The data represents the current level of technology and targets high-volume manufacturing to the largest extent possible. Also, flows crossing the system boundary have a recommended link to Ecoinvent data, or a request for an attentive selection of input data, depending on the user’s object of study. A distinction was made between the regular and an extended system boundary, wherein the processing of some smaller subparts was accounted for through proposals of ready-made Ecoinvent activities for production efforts. Results and discussion: An extensive new dataset representing electrical machine manufacturing is presented, and, together with the estimation of motor mass and configuration of article part I, it forms a comprehensive scalable LCI model of a typical automotive electric traction motor. New production data includes a complete motor factory, electrical steel production, and the fabrication of a neodymium-dysprosium-iron-boron (Nd(Dy)FeB) magnet. In addition, smaller, new datasets cover the composition of silicon steel, the making of electrolytic iron, enameling of copper wire, and die casting of aluminum. Conclusions: Successful data generation required “data building” from multiple sources and access to expert support. Transparent, well-explained, and disaggregated data records were found to be crucial for LCA data validation and usefulness.
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| 15. |
- Tillig, Fabian, 1984, et al.
(author)
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Design, operation and analysis of wind-assisted cargo ships
- 2020
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In: Ocean Engineering. - : Elsevier BV. - 0029-8018. ; 211:1, s. 1-23
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Journal article (peer-reviewed)abstract
- This study presents a novel approach to analytically capture aero- and hydrodynamic interaction effects on wind-assisted ships. Low aspect ratio wing theory is applied and modified to be used for the prediction of lift and drag forces of hulls sailing at drift angles. Aerodynamic interaction effects are captured by analytically solving the Navier-Stokes equation for incompressible, potential flow. The developed methods are implemented to a 4 degrees-of-freedom performance prediction model called “ShipCLEAN”, including a newly developed method for rpm control of Flettner rotors on a ship to maximize fuel savings. The accuracy of the model is proven by model- and full-scale verification. To present the variability of the model, two case study ships, a tanker and a RoRo, are equipped with a total of 11 different arrangements of Flettner rotors. The fuel savings and payback times are assessed using realistic weather from ships traveling on a Pacific Ocean route (tanker) and Baltic Sea route (RoRo). The results verify the importance of using a 4 degrees-of-freedom ship performance model, aero- and hydrodynamic interaction and the importance of controlling the rpm of each rotor individually. Fuel savings of 30% are achieved for the tanker, and 14% are achieved for the RoRo.
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| 16. |
- Johansson, Björn, 1975, et al.
(author)
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Power Level Sampling of Metal Cutting Machines for Data Representation in Discrete Event Simulation
- 2015
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In: International Journal of Production Research. - : Informa UK Limited. - 0020-7543 .- 1366-588X. ; 53:23, s. 7060-7070
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Journal article (peer-reviewed)abstract
- An extension to the application area for discrete event simulation (DES) has been ongoing since the last decade and focused only on economic aspects to include ecologic sustainability. With this new focus, additional input parameters, such as electrical power consumption of machines, are needed. This paper aim at investigating how NC machine power consumption should be represented in simulation models of factories. The study includes data-sets from three different factories. One factory producing truck engine blocks, one producing brake disc parts for cars and one producing forklift components. The total number of data points analysed are more than 2,45,000, where of over 1,11,000 on busy state for 11 NC machines. The low variability between busy cycles indicates that statistical representations are not adding significant variability. Furthermore, results show that non-value-added activities cause a substantial amount of the total energy consumption, which can be reduced by optimising the production flow using dynamic simulations such as DES.
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| 17. |
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| 18. |
- Engström, Rebecka Ericsdotter, 1984-
(author)
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Exploring cross-resource impacts of urban sustainability measures : an urban climate-land-energy-water nexus analysis
- 2022
-
Doctoral thesis (other academic/artistic)abstract
- In an increasingly urban world, cities' global resource uses grow. Two fundamental resources for making cities liveable are water and energy. These resources are also closely interlinked – systems that convert and deliver energy to cities require water, and urban water systems use energy. In addition, these two resource systems affect and are affected by land use and climate change. This ‘nexus’ between climate, land use, energy and water (CLEW) systems has been extensively studied in the past decade, mainly with a focus on national and transboundary CLEW systems. This doctoral thesis develops the CLEW nexus research from an urban perspective.Two quantitative analyses examine how different types of sustainability measures in cities affect intended and unintended CLEW systems. First, the CLEW impacts of a set of sustainability measures in New York City are assessed - from water conservation to emission reductions. Results show that every measure affects (to varying degrees) all studied sustainability dimensions - water, energy and climate - and that the impacts can be quantified through a reference-resource-to-service-system (RRSS).The second quantitative study focuses on how CLEW impacts from a city's sustainability efforts spread beyond local and international borders. It investigates how global water and land use are affected in alternative scenarios to achieve climate neutrality in 2030 in the town of Oskarshamn, Sweden, using an energy systems simulation model. The study finds that both the magnitude and the geographical distribution of land and water requirements vary between scenarios. A strategy to achieve climate neutrality that invests in electrification leads to increased national water use, while a strategy that relies on biofuels has a greater impact on water and land use internationally. When results are translated to interactions between the UN's sustainable development goals (SDGs), they reveal that SDG synergies and trade-offs are 'strategy-dependent': different options for achieving SDGs on energy, sustainable cities and climate action have varying consequences for the advancement of SDGs on sustainable water, food production and biodiversity.To shed light on how data challenges affect quantitative urban nexus studies, uncertainty assessments of selected thesis’ results are conducted and complemented with a thematic analysis of a set of recently published urban nexus papers. Together, they indicate that analytical choices, uncertainties in results and - as a consequence - research foci are influenced by data limitations in both this thesis and in other urban nexus studies.Lastly, the finding from the Oskarshamn analysis – that SDG interactions are strategy-dependent – is deliberated with experts within sustainability sciences and SDG interaction research. From this, a research agenda is proposed with measures to make SDG 'spillovers' visible in local level decision-making.Taken together, the thesis contributes to filling several knowledge gaps on how urban sustainability measures within the CLEW systems interact within and beyond city limits, and proposes analytical approaches to quantify these interactions. It further points out how current data challenges constrain quantitative urban nexus analyses and highlights research needs to improve data management as well as other key efforts to enable consideration of nexus interactions, including SDG 'spillovers', in cities' sustainability work.
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| 19. |
- Lindahl, Niklas, 1981, et al.
(author)
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Early stage techno-economic and environmental analysis of aluminium batteries
- 2023
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In: Energy Advances. - : Royal Society of Chemistry (RSC). - 2753-1457. ; 2:3, s. 420-429
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Journal article (peer-reviewed)abstract
- For any proper evaluation of next generation energy storage systems technological, economic, and environmental performance metrics should be considered. Here conceptual cells and systems are designed for different aluminium battery (AlB) concepts, including both active and passive materials. Despite the fact that all AlBs use high-capacity metal anodes and materials with low cost and environmental impact, their energy densities differ vastly and only a few concepts become competitive taking all aspects into account. Notably, AlBs with high-performance inorganic cathodes have the potential to exhibit superior technological and environmental performance, should they be more reversible and energy efficient, while at the system level costs become comparable or slightly higher than for both AlBs with organic cathodes and lithium-ion batteries (LIBs). Overall, with continued development, AlBs should be able to complement LIBs, especially in light of their significantly lower demand for scarce materials. Several aluminium battery concepts are evaluated at material, cell and system levels for technical, economic and environmental performance, which enables them to complement lithium-ion batteries in the future.
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| 20. |
- Vogl, Valentin, et al.
(author)
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A just transition towards a coal-free steel industry: perspectives from labour
- 2019
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In: 14th Nordic Environmental Social Science (NESS). ; , s. 1-30
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Conference paper (peer-reviewed)abstract
- Limiting global warming to ‘safe’ levels will require rapid and radical reductions of greenhouse gas emissions across all sectors of the global economy. The discontinuation of incumbent industrial structures, that will be an unavoidable part of such sustainability transitions, will disproportionally burden certain groups. Recent events including the social and political unrest linked to the imminent deterioration of coal communities and the fuel tax protests of the ’Gilets Jaunes’ have loudly shown that distributional effects of climate transitions cannot be ignored. Trade unions and NGOs have for some time called for an inclusive transition and brought increased attention to the justice dimension of energy transitions. In this paper, we analyse potential social impacts in a concrete case: the planned transition from coal to hydrogen-based steelmaking in the Swedish steel industry. To this end, we conduct a series of semi-structured interviews to examine the role of trade unions and the national trade union federation in re-orienting the industry. By doing so we aim to widen the scope of the just transitions debate to include process industries and to explore the concrete meaning of a just transition in the case of the planned transition of the Swedish steel industry. We analyse, on the one hand, the capacity of trade unions to influence the transition process, and, on the other hand, the potential social impacts of the transition on the labour force and local communities. As the transition of the Swedish steel sector kicks into gear, we highlight a number of social issues that should be addressed both within industry and through policy. We conclude that it is important to early on: include stakeholders in the process, bring up social and political aspects of the transition, and acknowledge and address potential conflicting interests associated with it.
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| 21. |
- Åström, Stefan, 1977
(author)
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Research and reflections on European air pollution policy support models
- 2019
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Doctoral thesis (other academic/artistic)abstract
- European emissions to air of SO2, NOx, PM2.5, NH3 and NMVOC still today cause harm to human health and the environment. These pollutants are associated with the premature death of ~400 000 people annually in the EU (25 000 perished in traffic accidents 2017). Improvements are expected but problems will persist. To abate these effects European countries are engaged in several international agreements, all dependent on interaction between science and policy. For some 15 years scientific decision support to policy-makers was based on integrated assessment models (IAM) combined with quantification of economic benefits in cost-benefit analysis (CBA) of proposed policies. However, in 2013 the European Commission changed approach and used CBA to model socio-economic optimal emission levels and used these levels as basis for a policy proposal. This new approach puts higher demand on model coverage and reliability. It can also be methodologically controversial. This thesis presents research and reflections on the robustness of air pollution policy support models used by the European Commission, with focus on IAM and CBA. Robustness over climate metrics is analysed with cost-effectiveness analysis of air pollution control options, with sensitivity analysis of metric choice. An SO2 decomposition analysis indicates if consideration of end-of-pipe control options is enough. Robustness of emission control strategies with respect to investment parameters is analysed with IAM, and CBA provides estimates of whether options to reduce emissions from international shipping should be considered in the modelling. Methodological issues are also reviewed. The results indicate that the models are robust with respect to climate metrics used and the focus on end-of-pipe SO2 options. The modelling of emission control can be sensitive to investment parameters and to the current exclusion of control options on ships. The methodological foundation of CBA is criticised but since environmental policies depend on support also from arenas outside science it remains unclear if CBA-shortcomings impairs the air pollution policy process. Regardless, there are arguments for inter alia complementing CBA with analyses based on non-economic decision rationales. Finally, the thesis provides insights and suggestions for air pollution policy modelling and research that should be considered in the future.
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| 22. |
- Bryngelsson, David, 1981
(author)
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Land-use competition and agricultural greenhouse gas emissions in a climate change mitigation perspective
- 2015
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Doctoral thesis (other academic/artistic)abstract
- Productive land for food production, bioenergy, or preservation of nature is a limited resource. Climate change mitigation puts additional pressure on land via higher demand for bioenergy to replace fossil fuels and via restrictions on deforestation—two processes that limit the availability of land for food produc- tion, and may thus also raise food prices. Methane and nitrous oxide emis- sions from agriculture may also need to be reduced to efficiently mitigate climate change. This thesis deals with this in three ways.In papers I–II, we estimate greenhouse gas emissions from food production for current diets and expected future developments, together with alternative di- etary developments and potential technical improvements in the agricultural sec- tor. Costs and possibilities for reaching climate goals are analyzed for the differ- ent diets. The results indicate that a phase out of ruminant products would cut mitigation cost in half, for staying below a 2◦C limit, and it may be necessary if the climate sensitivity is high.In papers III–IV, a conceptual and transparent partial equilibrium model of global land-use competition is developed, analyzed and applied. The model is to a large degree analytically explored and price differentials between crops are derived. The model is subjected to a detailed characterization of its mechanisms and parameters that are critical to the results. We conclude that the total amount of productive agricultural area and bioenergy yields are of crucial importance to the price impacts from large-scale introduction of bioenergy. We also show how limiting bioenergy production to marginal land could be difficult to implement in practice.In paper V, we use two established indicators for poverty and sensitivity to food-price changes to capture peoples’ vulnerability to rising food-prices in four Sub-Sahara African countries/regions. In contrast to previous studies, we include all food products instead of just one or a few main staples. We found that the vast majority of people are net consumers of food and that the inclusion of more than main staples increases their net position as consumers and thus vulnerability to high food prices.
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| 23. |
- Andersson, Karin, 1952, et al.
(author)
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Shipping and the Environment - Improving Environmental Performance in Marine Transportation
- 2016
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Book (other academic/artistic)abstract
- This book focuses on the interaction between shipping and the natural environment and how shipping can strive to become more sustainable. Readers are guided in marine environmental awareness, environmental regulations and abatement technologies to assist in decisions on strategy, policy and investments. You will get familiar with possible paths to improve environmental performance and, in the long term, to a sustainable shipping sector, based on an understanding of the sources and mechanisms of common impacts. You will also gain knowledge on emissions anddischarges from ships, prevention measures, environmental regulations, and methods and tools for environmental assessment. In addition, the book includes a chapter on thebackground to regulating pollution from ships. It is intended as a source of information for professionals connected to maritime activities as well as policy makers and interested public. It is also intended as a textbook in higher education academic programmes.
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| 24. |
- Thies, Fabian, 1984, et al.
(author)
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Wind-assisted, electric, and pure wind propulsion - the path towards zero-emission RoRo ships
- 2023
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In: Ships and Offshore Structures. - : Informa UK Limited. - 1754-212X .- 1744-5302. ; 18:8, s. 1229-1236
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Journal article (peer-reviewed)abstract
- Electrical and wind propulsion, together with energy stored in batteries and renewable energies harnessed onboard, can lead the way towards zero-emission ships. This study compares wind propulsion solutions and battery storage possibilities for a RoRo ship operating in the Baltic Sea. The ship energy systems simulation model ShipCLEAN is used to predict the performance of the zero-emission ship in real-life operating conditions. The study showcases how ships can be transferred from a conventional, diesel-powered to a zero-emission ship. For the zero-emission ship, all energy needed for auxiliaries and propulsion is taken from renewable sources onboard or from batteries. Challenges and opportunities, as well as necessary adaptions of the route and logistics, are discussed. Results of the study present which wind propulsion technology is the most suitable for the example RoRo ship, and how the installation of suitably sized battery packs for zero-emission operation affects the cargo capacity of the ship.
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| 25. |
- Johansson, Björn, 1975, et al.
(author)
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Evaluation and Calculation of Dynamics in Environmental Impact Assessment
- 2013
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In: IFIP Advances in Information and Communication Technology. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 1868-4238 .- 1868-422X. - 9783642403514 ; 397:1, s. 135-141
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Conference paper (peer-reviewed)abstract
- In ten years customers will select products not only based on price and quality but also with strong regard to the product value environmental footprint, including for example the energy consumed. Customers expect transparency in the product realization process, where most products are labeled with their environmental footprint. Vigorous companies see this new product value as an opportunity to be more competitive. In order to effectively label the envi-ronmental impact of a product, it is pertinent for companies to request the envi-ronmental footprint of each component from their suppliers. Hence, companies along the product lifecycle require a tool, not only to facilitate the computing of the environmental footprint, but also help reduce/balance the environmental impact during the lifecycle of the product. This paper proposes to develop a procedure that companies will use to evaluate, improve and externally advertise their product’s environmental footprint to customers.
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