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- Andersson, Karin, 1952, et al.
(författare)
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Criteria and Decision Support for A Sustainable Choice of Alternative Marine Fuels
- 2020
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 12:9, s. 3623-
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Tidskriftsartikel (refereegranskat)abstract
- To reach the International Maritime Organization, IMO, vision of a 50% greenhouse gas (GHG) emission reduction by 2050, there is a need for action. Good decision support is needed for decisions on fuel and energy conversion systems due to the complexity. This paper aims to get an overview of the criteria types included in present assessments of future marine fuels, to evaluate these and to highlight the most important criteria. This is done using a literature review of selected scientific articles and reports and the authors’ own insights from assessing marine fuels. There are different views regarding the goal of fuel change, what fuel names to use as well as regarding the criteria to assess, which therefore vary in the literature. Quite a few articles and reports include a comparison of several alternative fuels. To promote a transition to fuels with significant GHG reduction potential, it is crucial to apply a life cycle perspective and to assess fuel options in a multicriteria perspective. The recommended minimum set of criteria to consider when evaluating future marine fuels differ somewhat between fuels that can be used in existing ships and fuels that can be used in new types of propulsion systems
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- Andersson, Karin, 1952
(författare)
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Emission free propulsion for ships
- 2021
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Ingår i: Baltic Rim Economies BRE review. - 1459-9759. ; 2021:5, s. 26-26
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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- Andersson, Karin, 1952, et al.
(författare)
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Shipping and the Environment
- 2021
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Ingår i: International Encyclopedia of Transportation: Volume 1-7. ; 3, s. 286-293
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The sea provides the infrastructure for shipping, but it is also a very important part of the natural environment, providing many kinds of ecosystem services to man. More than 90% of international goods transport is performed by sea, and although shipping is the most energy efficient means of transport, it also causes impacts on nature, health, crops, and the built environment. The main part of emissions to air from shipping is related to the fuel. Traditionally, combustion engines using fossil heavy fuel oil (HFO) or diesel oil with emissions of sulfur, nitrogen oxides, particles, and other pollutants have been dominating. In order to decrease environmental impact, “zero emission” fuels and propulsion alternatives have been developed. The impact on the marine environment from, for example, oil spills and use of antifouling coatings on ships are other areas of concern. Shipping has a large challenge in becoming fossil-free and in developing “zero emission” technology in the coming decades.
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- Andersson, Karin, 1952
(författare)
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The shipping industry and the climate
- 2022
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Ingår i: Sustainable Energy Systems on Ships: Novel Technologies for Low Carbon Shipping. - 9780128244715 ; , s. 3-25
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- As by 2020, the past six years, including 2020, are likely to be the six warmest years on record and the global mean temperature was 1.2°C above the preindustrial level [1]. International agreements, the Kyoto Protocol (1997) and the Paris agreement (2016), has set the aim to keep a global temperature rise during this century well below 2°C above pre-industrial levels. The anthropogenic inflow of GHGs to the atmosphere from the shipping industry was estimated by the IMO to totally around 2.5–3% of the global emissions in 2018 (or 1076 million tonnes). This is an increase by 9.6% since the previous study in 2014. The IMO projects the future emissions to increase from 1000 Mt CO2 in 2018 to 1000 to 1500 Mt CO2 in 2050 in a “Business as Usual”, BAU, scenario. Two years after the Paris agreement, the IMO adopted a vision, followed by a plan for implementation, in which a global goal of 50% reduction in GHG emissions from shipping by 2050 compared to 2008, and a total phase-out “within this century” is stated. Action from the IMO has started with a data collection system for fuel oil consumption. Ships of >5000 gross tonnage are required to collect consumption data fuel oil use and data on transport work. The European Union has started work on emission decrease with demands on Monitoring, Reporting and Verification of CO2 emissions from large ships (>5000 tonnes) using EU ports. Also here further measures are expected. At present here are many different initiatives, internationally, from countries as well as from shipping companies and shipowners to find ways towards “zero carbon shipping”. The different regulations and incentives introduced will help on the way, but still there is a need for more strict regulations or stronger incentives. The present initiatives give a large potential to make shipping and sea transport an important player also in a carbon neutral, sustainable society.
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- Erestam, Sofia, et al.
(författare)
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Associations between intraoperative factors and surgeons' self-assessed operative satisfaction.
- 2020
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Ingår i: Surgical endoscopy. - : Springer Science and Business Media LLC. - 1432-2218 .- 0930-2794. ; 34:1, s. 61-68
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Tidskriftsartikel (refereegranskat)abstract
- Little is known concerning what may influence surgeon satisfaction with a surgical procedure and its associations with intraoperative factors. The objective was to explore the relationships between surgeons' self-assessed satisfaction with performed radical prostatectomies and intraoperative factors such as technical difficulties and intraoperative complications as reported by the surgeon subsequent to the operation.We utilized prospectively collected data from the controlled LAPPRO trial where 4003 patients with prostate cancer underwent open (ORP) or robot-assisted laparoscopic (RALP) radical prostatectomy. Patients were included from fourteen centers in Sweden during 2008-2011. Surgeon satisfaction was assessed by questionnaires at the end of each operation. Intraoperative factors included time for the surgical procedure as well as difficulties and complications in various steps of the operation. To model surgeon satisfaction, a mixed effect logistic regression was used. Results were presented as odds ratios (OR) with 95% confidence intervals (CI).The surgeons were satisfied in 2905 (81%) and dissatisfied in 702 (19%) of the surgical procedures. Surgeon satisfaction was not statistically associated with type of surgical technique (ORP vs. RALP) (OR 1.36, CI 0.76; 2.43). Intraoperative factors such as technical difficulties or complications, for example, suturing of the anastomosis was negatively associated with surgeon satisfaction (OR 0.24, CI 0.19; 0.30).Our data indicate that technical difficulties and/or intraoperative complications were associated with a surgeon's level of satisfaction with an operation.
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- Malmgren, Elin, 1992, et al.
(författare)
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The environmental performance of a fossil-free ship propulsion system with onboard carbon capture – a life cycle assessment of the HyMethShip concept
- 2021
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Ingår i: Sustainable Energy & Fuels. - : Royal Society of Chemistry (RSC). - 2398-4902. ; 5:10, s. 2753-2770
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Tidskriftsartikel (refereegranskat)abstract
- The climate impact caused by the shipping industry has increased over the past decades despite attempts toimprove the energy efficiency of vessels and lower induced emissions. A tool in reducing climate and otherenvironmental impacts is new low emissions propulsion technologies. These new technologies need toreduce harmful emissions not only in the tailpipe but also over the entire life cycle. This study uses lifecycle assessment to investigate the life cycle environmental impact of a propulsion concept currentlyunder development: the HyMethShip concept. The HyMethShip concept combines electro-methanolenergy storage, an onboard pre-combustion carbon capture system, and a dual fuel internal combustionengine. The concept aims for an almost closed CO2 loop by installing CO2 capture onboard.The CO2 isunloaded in port and converted into electro-methanol which is used to fuel the ship again. This is madepossible by a pre-combustion process converting electro-methanol to hydrogen and CO2. Theassessment is conducted from well-to-propeller and focuses on ship operation in the North Sea in 2030.The results indicate that this technology could be an alternative to reduce the climate impact fromshipping.The results show a lower impact on acidification, climate change, marine eutrophication,particulate matter, photochemical ozone formation, and terrestrial eutrophication compared to internalcombustion engines run on either marine gas oil (0.1% sulphur content), biogenic methanol, fossilmethanol, or electro-methanol. Electricity with low climate and environmental impact is likely requiredto achieve this, and low NOx emissions from combustion processes need to be maintained. A potentialtrade-off is higher toxicity impacts from the HyMethShip concept compared to most other options, dueto metal needs in wind power plants.
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- Rijpkema, Jelmer Johannes, 1982, et al.
(författare)
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Exhaust waste heat recovery from a heavy-duty truck engine: Experiments and simulations
- 2022
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Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 238
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Tidskriftsartikel (refereegranskat)abstract
- Waste heat recovery using an (organic) Rankine cycle is an important and promising technology for improving engine efficiency and thereby reducing the CO2 emissions due to heavy-duty transport. Experiments were performed using a Rankine cycle with water for waste heat recovery from the exhaust gases of a heavy-duty Diesel engine. The experimental results were used to calibrate and validate steady-state models of the main components in the cycle: the pump, pump bypass valve, evaporator, expander, and condenser. Simulations were performed to evaluate the cycle performance over a wide range of engine operating conditions using three working fluids: water, cyclopentane, and ethanol. Additionally, cycle simulations were performed for these working fluids over a typical long haul truck driving cycle. The predicted net power output with water as the working fluid varied between 0.5 and 5.7 kW, where the optimal expander speed was dependent on the engine operating point. The net power output for simulations with cyclopentane was between 1.8 and 9.6 kW and that for ethanol was between 1.0 and 7.8 kW. Over the driving cycle, the total recovered energy was 11.2, 8.2, and 5.2 MJ for cyclopentane, ethanol, and water, respectively. These values correspond to energy recoveries of 3.4, 2.5, and 1.6%, respectively, relative to the total energy requirement of the engine. The main contribution of this paper is the presentation of experimental data on a complete Rankine cycle-based WHR system coupled to a heavy-duty engine. These results were used to validate component models for simulations, allowing for a realistic estimation of the steady-state performance under a wide range of operating conditions for this type of system.
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- Rijpkema, Jelmer Johannes, 1982, et al.
(författare)
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Experimental investigation and modeling of a reciprocating piston expander for waste heat recovery from a truck engine
- 2021
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 186
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Tidskriftsartikel (refereegranskat)abstract
- Waste heat recovery using an (organic) Rankine cycle has the capacity to significantly increase the efficiency of heavy-duty engines and thereby reduce fuel consumption and CO2 emissions. This paper evaluates a reciprocating piston expander used in a Rankine cycle for truck waste heat recovery by quantifying its performance on the basis of experimental results and simulations. The experimental results were obtained using a setup consisting of a 12.8 L heavy-duty Diesel engine connected to a Rankine cycle with water and are used to calibrate a semi-empirical expander model. At an engine power between 75 and 151 kW, this system recovered between 0.1 and 3 kW, resulting in an expander filling factor between 0.5 and 2.5, and a shaft isentropic effectiveness between 0.05 and 0.5. The calibrated model indicated that the heat loss (16%), mechanical loss (6–25%), pressure drop (13–42%), and leakage (25–75%) all contributed significantly to the expander performance loss. A simulation study with acetone, cyclopentane, ethanol, methanol, and R1233zd(E), showed that a change of working fluid significantly impacts the expander performance, with the filling factor varying between 0.5 and 2.2 and the effectiveness between 0.01 and 0.5, depending on the working fluid, expander speed, and pressure ratio. The results of the optimization of the built-in volume ratio and inlet valve timing during a typical long haul driving cycle showed that acetone and R1233zd(E) provided the highest available power around 3 kW absolute, or 2.2% relative to the engine. The main contributions of this paper are the presentation of experimental results of an engine coupled to a Rankine cycle, and the quantification of performance losses and the effect of working fluid variation using an adapted semi-empirical expander model, which allows for a selection of the working fluid and geometrical modifications giving optimal performance during a long haul driving cycle.
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