| 61. |
- Selvakkumaran, Sujeetha, 1985, et al.
(författare)
-
Electric Vehicle (EV) Transition in Thailand: Is it Beneficial?
- 2018
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Ingår i: PROCEEDINGS OF THE 2018 INTERNATIONAL CONFERENCE AND UTILITY EXHIBITION ON GREEN ENERGY FOR SUSTAINABLE DEVELOPMENT (ICUE 2018). - 9789748257990
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Konferensbidrag (refereegranskat)abstract
- The adoption of electric vehicles (EV) is effectively a problem of socio-technical transitions and comes with its complexities. The Thai Energy Efficiency Development Plan includes the adoption of EV as a voluntary measure to increase the energy effectiveness of its transport sector and to mitigate GHG emissions. But, there are other important social, technological, economic and policy factors which need to be thoroughly investigated before the EV transition is attempted in Thailand, since the environmental cost may outweigh the benefits of the EV transition. The methodology used is based on systems thinking and called Causal Loop Diagrams (CLD). In CLD, the factors underpinning the benefits accruing from the EV transition in Thailand are characterized as causal relationships and feedback loops. Preliminary CLD investigation into the factors for EVs show the technological factor EV efficiency levels and their cost (economic factor) are important in determining the GHG reduction benefit, along with the grid emission factor.
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| 62. |
- Shami, Siavash, et al.
(författare)
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Assessments of ground subsidence along the railway in the Kashan plain, Iran, using Sentinel-1 data and NSBAS algorithm
- 2022
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Ingår i: International Journal of Applied Earth Observation and Geoinformation. - : Elsevier. - 1569-8432 .- 1872-826X. ; 112
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Tidskriftsartikel (refereegranskat)abstract
- The 110-kilometer-long Qom-Kashan railway is one of the busiest lines in Iran, passing through the Kashan plain. The majority of Iran's plains have subsided in recent years as a result of uncontrolled groundwater extraction, and the Kashan plain is no exception. In this study, ground surface displacement in the Kashan plain region and its impact on the railway were investigated using New Small Baseline Subset (NSBAS) in up-down and east–west directions using descending and ascending Sentinel-1 data collected between 2015 and 2021. Our results indicate that the Kashan plain is subsiding more than 90 mm/year. The study of the local areas around the railway which passes through the study area revealed that the rate of vertical velocity in some locations reaches –23 mm/year, while the rate of east–west velocity is insignificant and is approximately ±2 mm/year. Additionally, a method for analyzing the railway's stability based on longitudinal profiles along the railway is presented. Our findings suggest that more than 60% of the railway line is subject to variable amounts of subsidence. Additionally, a region of approximately one kilometer of the railway has been classified as a risk zone due to relatively fast local deformation. After examining the effect of various factors, it was determined that uncontrolled groundwater extraction in agricultural areas contributed to the subsidence in this area. Our results show that the presented stability control approach in this study is highly reliable for creating hazard profiles for linear structures, such as railways.
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| 63. |
- Shavalieva, Gulnara, 1987, et al.
(författare)
-
Environmental, health and safety assessment of post-combustion CO2 capture processes with phase-change solvents
- 2021
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Ingår i: Sustainable Production and Consumption. - : Elsevier BV. - 2352-5509. ; 25, s. 60-76
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Tidskriftsartikel (refereegranskat)abstract
- A class of solvents for chemisorption-based CO2 capture, phase-change solvents, promises significant energy reductions due to liquid-liquid phase separation and partial solvent recycling before CO2 desorption. Although energy consumption is a critical aspect of the CO2 capture process sustainability, a holistic evaluation of health, safety, and environmental impacts is required to confirm the beneficial performance of processes employing phase-change solvents compared to conventional alternatives. This study outlines a method for combining the life cycle and environmental, health and safety hazard assessment. The method is applied for the first time on processes employing two different exemplary phase-change solvents, a reference aqueous solution of methylcyclohexylamine (MCA) and a novel mixture of cyclohexylpropane-1,3-diamine (S1N) and dimethylcyclohexylamine (DMCA). The results show that phase-change solvents have the potential to be a better alternative to conventional amine (i.e., MEA) solvent systems due to the reduced reboiler duty and lower impact on the environment. However, additional care might need to be taken to prevent the potential accumulation of the carcinogenic nitrosamines in the system.
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| 64. |
- Sparovek, Gerd, 1962, et al.
(författare)
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Asymmetries of cattle and crop productivity and efficiency during Brazil's agricultural expansion from 1975 to 2006
- 2018
-
Ingår i: Elementa. - : University of California Press. - 2325-1026. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Brazil has global importance for food production and conservation of natural resources. The country has plans to increase yields and commitments to decrease deforestation that require higher productivity. Plans and policies for the growth of Brazilian agriculture, however, have been made without an integrated analysis of the harvest and not supported by a universal metric regarding its efficiency. Applying methods to model flows of energy and matter along food supply chains for agricultural production from 1975 to 2006, we found that crop and cattle harvests and their productivity have increased during the last four decades in consolidated and deforestation frontier regions. Yet in 2006, crop protein production was 20 times larger than cattle protein, using an area 2.6 times smaller than pastures. Crop protein productivity was 0.25 ton.ha(-1) with emissions of 2 ton GHG per ton of protein, while cattle productivity was 0.01 ton.ha(-1) with emissions of 283 ton GHG per ton of protein. From 1975 to 2006, the portion of crop protein and energy going to feed increased while the portion going to direct human consumption decreased. Our findings suggest that more efficient food systems would be achieved by a combination of intensification of cattle systems, optimization of feed-meat systems and an increase in the share of the consumption of crops as a source of protein. We suggest an initial road map to the expansion of the cultivated area and intensification of agriculture for zero deforestation, efficient and sustainable land use and food systems where cattle pasture intensification is a transition that will last until the expansion of crops replace all pasture present on suitable arable land. During this transition, pasture area will decrease until it is limited only to marginal non-arable lands. Such change could be achieved by a robust strategy that combines penalties and incentives and prevents the risks of a rebound effect for the intensification of agriculture.
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| 65. |
- Wasserbaur, Raphael, 1989-, et al.
(författare)
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What if everyone becomes a sharer? A quantification of the environmental impact of access-based consumption for household laundry activities
- 2020
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Ingår i: Resources, Conservation and Recycling. - : Elsevier BV. - 0921-3449 .- 1879-0658. ; 158
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Tidskriftsartikel (refereegranskat)abstract
- In order to meet the EU's climate and resource efficiency targets, changes in our daily-life behaviours, as well as business models, are urgently necessary. More insights are needed to make real changes based on research with a systems perspective. We developed a system dynamics model to analyse the environmental benefits of a transition from ownership-based to access-based household laundry activities. The model considers demographic, technological and behavioural aspects and thereby assesses the environmental impact of laundry activities. The model is applied to the Swedish as well as the European context and allows cross-country comparisons. The results indicate a significant potential of the sharing economy. The higher utilisation of shared machines and extended lifespans of the machines can cut greenhouse gas emissions by a third and lower raw material usage overall and lower primary raw material in production due to higher recycling rates. The carbon intensity of the energy mix is a crucial factor for the environmental consequences that arise through changes in energy usage due to sharing economy practices. This case study shows the value of adopting policies that could promote sharing and extended life spans.
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| 66. |
- Wickerts, Sanna, 1992, et al.
(författare)
-
Energy storage with less metal scarcity? Prospective life cycle assessment of lithium-sulfur batteries with a focus on mineral resources.
- 2021
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In order to reduce the global dependency on fossil fuels by adopting renewable energy technologies and advancing electromobility, batteries are a key technology. Lithium-ion batteries (LIBs) are currently the dominant rechargeable battery technology, mainly due to their high energy density. However, most LIBs contain a number of geochemically scarce metals, e.g.cobalt, lithium and nickel. The production of LIBs is furthermore associated with considerable environmental impacts. Battery researchers and companies therefore try to develop the next generation batteries (NGBs) with the same or even higher energy densities than LIBs, while requiring less of scarce metals and causing lower environmental impacts. One promising NGB technology is the lithium-sulfur (Li-S) battery, with a potential to significantly improve energy density as compared to current state-of-the-art LIBs. Although Li-S batteries still face a number of scientific and technical challenges, they have a significant advantage over LIBs from a resource point of view: the cells do not require any scarce metals besides lithium. Using prospective life cycle assessment, we will assess the life-cycle environmental impacts of Li-S batteries and compare them to those of LIBs, both modeled at large-scale production. In order to investigate the effect of using less scarce metals on resource impacts, the mineral resource impact category will be given extra attention. We will therefore include a range of mineral resource impact assessment methods, e.g. the abiotic depletion indicator, the surplus ore indicator, and the recently developed crustal scarcity indicator, which takes an explicit long-term perspective on elemental resources in the Earth’s crust. The overall aim is thus to compare the prospective life-cycle impacts of this particular NGB to those of LIBs, with a focus on mineral resources.
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| 67. |
- Willskytt, Siri, 1989
(författare)
-
How can consumables be made more resource efficient? Environmental and resource assessment of measures
- 2018
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The global population growth paired with increasing consumption per capita puts resource efficiency and sustainability on the political agenda. Consequently, the need for resource-efficient and sustainable products, including consumables, is expected to increase in the future. Strategies and measures for resource-efficient products are being developed, however, with less focus on consumables. This thesis aims to investigate how consumables can be made more resource efficient. The research was carried out in two parts. First, a life cycle assessment was carried out on a selected consumable, namely an incontinence product. The aim was to investigate the potential to improve the resource efficiency of incontinence products by assessing four different resource efficiency (RE) measures which could be applied within a short time frame using current technology. The measures included reduce losses in production, change material composition to a larger proportion of renewables, shift to a partly multiple-use product and improve the use of the product through customisation. The second part of this thesis focused on synthesising learnings from a number of assessment studies. The analysis was based on typologies formulated for mapping resource efficiency measures and product characteristics. This resulted in a number of findings detailing under which circumstances resource efficiency measures yield environmental and resource benefits, as well as when there are possible trade-offs. The assessment studies of consumables were selected for a more detailed analysis in this thesis. Based on the review of cases and the typology of RE measures, the following RE measures were found applicable to consumables: reduce losses in production, reduce material use in products, change material in product, use effectively, shift to multiple-use products, reduce use of auxiliary materials and energy, recycle, digest anaerobically or compost, recover energy, and landfill. These are more measures which could potentially be applied to consumables than commonly discussed in the circular economy literature. Moreover, the identified measures among the cases all showed potential to improve resource efficiency. For the measure shift to multiple-use product, it was important for the product to last enough times to outweigh the environmental impact from production. In addition, an efficient maintenance system using electricity with low fossil content was an important element for achieving RE. When changing the material in a product, a risk of burden shifting between environmental impact categories was identified. Moreover, the measures applied to the incontinence products were found to be widely combinable, which could ultimately lead to greater resource efficiency. Others findings were that some measures are interdependent and that many, if not most, are dependent on design.
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| 68. |
- Zackrisson, Mats, et al.
(författare)
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Case study LCA on automotive light-weighting, using different datasets
- 2019
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Ingår i: The 9th International Conference on Life Cycle Management Abstract book.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Goal(s) Practitioners need quick but accurate methods for decision making when choosing materials in e.g. car chassis components. Simplified LCA is commonly used for this but choice of database, impact assessment method, material source and system boundaries can distort results and decision-making. This case study investigating steel versus aluminium in a cars roof evaluates effects from making lighter vehicles and demonstrates how the calculation results differ depending on choice of datasets. The impact of sourcing recycled or virgin material and depending on carbon intensity of energy source is assessed. Implications regarding future development and LCA modelling of e.g. light-weighting of electric cars is discussed. Method(s) The model considers manufacturing of a car roof from two optional materials, aluminium and steel, and the difference in fuel/electrical consumption for 10 years. The LCA system model compares the environmental impact of the material production with the weight-induced incremental fuel consumption impact of carrying the roof. The system boundary includes all life cycle phases, but in line with EPD system rules, end of life recycling is considered at the input material level. Cars are regulated to 85% material recycling, with near 100% for metal chassis.[MZ1] Also, from overview analysis of component production plants (stamping and joining) the chassis production difference was omitted. The functional unit is use of a car roof during car life cycle. A 17 kg steel roof is compared to a 7 kg aluminium roof, where the requirement of functionality stays the same for the roof regardless of the material chosen. In this study the following impact categories are used: -Climate impact -Acidification -Ground-level ozone (Photochemical oxidation) -Overfertilization (Eutrophication) Cost impact is also calculated to compare with literature. The evaluation only considers the effect of light-weighting a car depending on its energy source. It cannot be used to compare cars using different energy sources. The system boundaries and functional unit does not include the production of engines nor anything else of the car except the roof. Thus, the study is limited to comparing differences in the material production with the weight-induced energy consumption changes. Results. The study validates earlier studies on climate, eutrophication and economic gains in changing car body. For photochemical oxidation and acidification, the result differs depending on database, no robust conclusion can be. One dataset always gives reduced environmental impact on the chosen categories. The reason is that these data incorporates the effects of future recycling. This could be interpreted as in a system with effective end-of-life recycling and a high use of recycled materials, all investigated impacts would be reduced by light-weighting. For electric cars, light-weighting of chassis can minimise battery size and/or increase drive range. Adaptions for other materials must consider that the assumption of negligible impact changes in the car manufacturing plant is only true for metal plate in a mixed model line, thus the component plant has to be accounted for. Also, many reinforced plastic compounds are not recycled but incinerated, thus EoL combustion need to be accounted for.
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| 69. |
- Murekatete, Rachel Mundeli, 1981-
(författare)
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Sensitivity, Variation, and Application of Least-Cost Path Models in Landscape Connectivity Analysis and Corridor Planning
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In recent decades, Rwanda has been affected by the loss and fragmentation of natural habitats for native species of animals and plants. As a consequence, landscape connectivity—i.e., the degree to which a landscape facilitates or impedes the movement of organisms between resource patches—has considerably weakened or is even completely lost, causing detrimental effects on biodiversity, notably the reduction of populations of key native species. In order to counter this problem, one potential solution currently being explored by local planners in Rwanda consists of establishing conservation corridors for organisms to move safely between their habitat remnants. Specifically, this thesis was inspired by a project initiated by the Dian Fossey Gorilla Fund International, a conservation non-governmental organization (NGO) based in Rwanda, which consists of establishing a conservation corridor for pollinators.For their capabilities of storing, processing, and visualizing landscape data, geographic information systems (GIS) have been increasingly popular among conservation biologists and practitioners. Of particular relevance to connectivity analysis and corridor planning is the least-cost path model. A typical use of this model is such that one first estimates the cost for a certain action (e.g., movement by an organism or acquisition by a government) at each location of a given landscape and represents the results in the form of a raster surface, and then measures the degrees of connectivity between patches of interest in terms of effective distances, which are equated with least-cost path distances over the raster cost surface. While the least-cost path model is easy to use and available in virtually any commercial raster-based GIS, we observe that users of it often overlook some important assumptions, the violation of which might greatly affect the validity of the model’s outcome.The goal of this thesis is to provide a scientific contribution to landscape connectivity analysis and conservation corridor planning by 1) investigating the potential misuse or abuse of the conventional least-cost path model when sufficient information is not available on the underlying cost surface, 2) proposing an alternative model under such a circumstance and 3) demonstrating its relevance to conservation practice. More specifically, for the model to work, it is explicitly or implicitly assumed that, the optimality of a path is evaluated as the sum of the cost-weighted lengths of all its segments—cost-weighted, i.e., multiplied by their underlying cost values. The validity of this assumption must be questioned, however, if cost values are measured on a scale—e.g., an ordinal scale of measurement in Stevens’s typology—that does not permit arithmetic operations. In a typical practice of landscape connectivity analysis and corridor planning, the raster cost surface is created by transforming one or more sets of values (e.g., land cover type, land ownership, and elevation) attributed to cells into another set of such values (representing cost) through a function reflecting one or more criteria. A question arises: how certain can one be about the correctness of such a cost estimation function?There are at least four issues in the application of the least-cost path model to landscape connectivity analysis and corridor planning under uncertainty. First, while it is generally anticipated that different cost estimation functions lead to different least-cost paths (hence to different effective distances or different corridor locations), little is known on how such differences arise (or do not arise). Second, while it is generally recognized that the location and length of a least-cost path are both sensitive to the spatial resolution of the raster cost surface, little is known if they are always sensitive in the same way and to the same degree and if not, what makes them more (or less) sensitive. Third, when it is difficult to establish a fully connected corridor between target habitat areas (e.g., because of surrounding anthropogenic activities), the least-cost path (which is by definition fully connected) may not be useful at least in its original form. Lastly, even if the conventional least-cost path model may have inconsistent results in theory, it may well be continued to be used in practice, unless there is a sound alternative to it.The issues raised above are addressed through four studies corresponding to four respective papers which are appended to this thesis. While the first three studies use artificial landscape data generated by computers with varying spatial and non-spatial characteristics, the fourth study uses data on a real landscape. The first study (Paper 1) evaluates how the locations and lengths of least-cost paths (the latter of which are referred to as least-cost distances) vary with change in cost estimation parameters. This is done through a series of computational experiments, in which each of the artificial landscapes is converted into different cost surfaces by systematically varying parameters of a cost-estimation function, on which least-cost paths are generated. The locations and lengths of those paths are statistically analyzed to find sources of their variation. The second study (Paper 2) investigates how the least-cost distance is affected by the spatial resolution of the corresponding cost surface. This is also done through a series of computational experiments, in which each of the artificial landscapes is converted into a cost surface, which is, in turn, converted into different cost surfaces (different, i.e., only in their spatial resolutions) by systematically aggregating grid cells. Then, the statistical behavior of the ratio of the least-cost distance measured on a lower-resolution cost surface to that measured on a higher-resolution cost surface is analyzed. The third study (Paper 3) proposes the mini-max path model as an alternative to the least-cost path model. Unlike the conventional model (in which the optimality of a path is based on the sum of its length multiplied by the underlying cost values), the alternative model determines the optimality of a path using the length of a segment(s) of the path that intersects the cells having the maximum cost value (with a special tie-breaking rule). The performances of the two models are tested in one of the following two assumptions at a time: the cost values are measured on an ordinal scale or on a ratio scale. The fourth study (Paper 4) applies the model proposed in the third study to an ongoing conservation project of the Dian Fossey Gorilla Fund International that plans to design a ‘stepping-stone’ corridor—which is not fully connected but takes the form of a sequence of fragmented forest patches—between two core habitat areas of pollinator birds between two protected areas in Rwanda. The project does not have complete information on the study area and the target species and thus the project staff can only rank land cover types in terms of their suitability/cost for being part of the corridor. The utility of the model is tested with different assumptions on the behavior of the birds (e.g., minimum stepping stone size) as well as on the cost associated with the implementation of the corridor (e.g., cost for planting shrubs along the corridor to encourage the birds to use it).The first study finds that the same pair of terminal cells may well be connected by different least-cost paths on different cost surfaces though derived from the same landscape data. The variation among those paths is highly sensitive to the forms of spatial and non-spatial distributions of landscape elements (which cannot be controlled by users of the least-cost path model) as well as by those of cost values derived from them (which may be, at least indirectly, controlled by users of the model). The second study finds that least-cost distances measured on lower-resolution cost surfaces are generally highly correlated with—and useful predictors of—effective distances measured on higher-resolution cost surfaces. This relationship tends to be weakened when linear barriers to connectivity (e.g., roads and rivers) exist, but strengthened as distances increase and/or when linear barriers (if any) are detected by other presumably more accessible and affordable sources such as vector line data. The third study confirms the effectiveness of the conventional least-cost path model on ratio-scaled cost surfaces but finds that the alternative mini-max path model is mathematically sounder if the cost values are measured on an ordinal scale and practically useful if the problem is concerned not with the minimization of cost but with the maximization of some desirable condition such as suitability. The fourth study demonstrates the utility of the mini-max path model by effectively casting the stepping stone corridor problem as a special case of it. The model allows for a rapid first delineation of candidate routes for stepping stone corridors and facilitates the early exploratory stages of conservation projects.Major implications of this thesis to the research and practice in landscape connectivity analysis and conservation corridor planning with raster-based GIS are summarized as follows.When sufficient information is available for quantification of cost values, the conventional least-cost path model is a reasonable approach to use.However, it is worth trying or at least acknowledging alternatives that do not rely on the quantitative-cost assumption if the value of each cell only indicates the ordinal category of cost of intersecting that cell. Note in particular that information used for cost estimation in practice (e.g., expert opinions or public surveys) are often of subjective and qualitative nature.The highest-resolution data may not always be most effective—much less, most cost-effective—for the task being undertaken. The choice of spatial resolution of th
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| 70. |
- Ekener, Elisabeth, 1963-, et al.
(författare)
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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
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526 .- 1879-1786. ; 181, s. 337-351
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Tidskriftsartikel (refereegranskat)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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