SwePub - search: AMNE:(ENGINEERING AND TECHNOLO...

Enumeration	Reference	Cover	Find
1.	Thomas, Jean-Baptiste, et al. (author) A comparative environmental life cycle assessment of hatchery, cultivation, and preservation of the kelp Saccharina latissima 2021 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.
2.	Mathern, Alexandre, 1986, et al. (author) Concrete Support Structures for Offshore Wind Turbines: Current Status, Challenges, and Future Trends 2021 In: Energies. - : MDPI AG. - 1996-1073 .- 1996-1073. ; 14:7 Research review (peer-reviewed)abstract Today’s offshore wind turbine support structures market is largely dominated by steel structures, since steel monopiles account for the vast majority of installations in the last decade and new types of multi-leg steel structures have been developed in recent years. However, as wind turbines become bigger, and potential sites for offshore wind farms are located in ever deeper waters and ever further from the shore, the conditions for the design, transport, and installation of support structures are changing. In light of these facts, this paper identifies and categorizes the challenges and future trends related to the use of concrete for support structures of future offshore wind projects. To do so, recent advances and technologies still under development for both bottom-fixed and floating concrete support structures have been reviewed. It was found that these new developments meet the challenges associated with the use of concrete support structures, as they will allow the production costs to be lowered and transport and installation to be facilitated. New technologies for concrete support structures used at medium and great water depths are also being developed and are expected to become more common in future offshore wind installations. Therefore, the new developments identified in this paper show the likelihood of an increase in the use of concrete support structures in future offshore wind farms. These developments also indicate that the complexity of future support structures will increase due to the development of hybrid structures combining steel and concrete. These evolutions call for new knowledge and technical know-how in order to allow reliable structures to be built and risk-free offshore installation to be executed.
3.	Herre, Lars, 1990-, et al. (author) Simplified model of integrated paper mill for optimal bidding in energy and reserve markets 2020 In: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 279 Journal article (peer-reviewed)abstract Due to the increased use of variable renewable energy sources, more capacity for reserves is required. Non-generating resources such as large industrial consumers can arbitrage energy prices and provide reserve capacity by exploiting the inherent flexibility in selected industrial processes. A large enough industrial consumer can capitalize on this flexibility through optimized bidding in electricity markets. In this work, the day-ahead cost minimization of a risk-averse pulp and paper mill is formulated as a two-stage stochastic problem, considering thermodynamic and electrical constraints. The bids in the energy and reserve markets are jointly optimized subject to price uncertainty as well as uncertainty of frequency realization. The results of a case study in Sweden display a significant economic benefit in exploiting the flexibility of integrated pulp and paper mills with electric boilers. The expected cost of the pulp and paper mill resulting from different strategies are compared and the risk-aversion of the pulp and paper mill is investigated. Reserve offers are mainly facilitated by fast-acting electric boilers and supported by flexibility in the steam network. We show that reserve offers can significantly improve the profitability of the pulp and paper mill.
4.	Jiao, Yang, et al. (author) Analysis of two hybrid energy storage systems in an off-grid photovoltaic microgrid : A case study 2020 In: Proceedings IEEE PES Innovative Smart Grid Technologies Conference Europe. - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 554-558 Conference paper (peer-reviewed)abstract In recent years, driven by global environmental issues, a growing number of renewable energy sources (RESs) have been developed. Microgrids have been confirmed as an important part in the increasing penetrations of renewable energy and the shift from a centralized paradigm to decentralized electricity production. The energy storage system (ESS) is a critical component that affects the development of microgrids. Combining advantages from different energy storage technologies, a hybrid energy storage system (HESS) can satisfy multiple requirements in microgrids. This paper compares the single battery system with the battery-supercapacitor (SC) HESS and the battery-flywheel HESS in an isolated photovoltaic (PV) power microgrid. Results show that both the SC and the flywheel distinctly reduce the battery charging and discharging powers and the required capacity of the battery. Therefore, the stresses and the needed size of the battery are reduced and the battery lifetime is extended.
5.	Lindahl, Niklas, 1981, et al. (author) Early stage techno-economic and environmental analysis of aluminium batteries 2023 In: Energy Advances. - : Royal Society of Chemistry (RSC). - 2753-1457. ; 2:3, s. 420-429 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.
6.	von Platten, Jenny, et al. (author) Renovating on unequal premises : A normative framework for a just renovation wave in swedish multifamily housing 2021 In: Energies. - : MDPI. - 1996-1073. ; 14:19 Journal article (peer-reviewed)abstract While the energy transition of the EU housing stock is now being intensified with the launch of the Renovation Wave, economic inequalities are increasing in many OECD countries, which has effects on housing-related inequalities and the demand of affordable housing. The Renovation Wave is thus an opportunity to improve housing quality for low-income households, but also entails risks for increased rents. In Sweden, the standard of housing is relatively high and energy poverty in multifamily housing is rare, meaning that there are limited social benefits to be achieved from extensive energy retrofitting; moreover, Sweden lacks a social housing sector, which limits protection of the worst-off residents. This paper thus explores whether the limited social benefits of the Renovation Wave weigh up against the risks that it entails for the worst-off in the Swedish context. This is done within a normative framework for just energy transitioning that is developed within the context of the Renovation Wave and increasing economic inequalities, consisting of four ordered principles: (1) The equal treatment principle; (2) The priority principle; (3) The efficiency principle; and (4) The principle of procedural fairness. Analysis showed that to be considered just according to our framework, the Swedish energy transition of housing should, in contradistinction to what is suggested in the Renovation Wave, limit the imposition of extensive energy retrofitting in low-income areas. Finally, having identified a mismatch between the most effective approaches in terms of energy savings and the most acceptable approaches in terms of social justice, we offer policy recommendations on how to bridge this mismatch in a Swedish context. © 2021 by the authors.
7.	Galkin, Nikolai, et al. (author) On Modelling of Edge Datacentre Microgrid for Participation in Smart Energy Infrastructures 2022 In: IEEE Open Journal of the Industrial Electronics Society. - : Institute of Electrical and Electronics Engineers Inc.. - 2644-1284. ; 3, s. 50-64 Journal article (peer-reviewed)abstract Datacentres are becoming a sizable part of the energy system and are one of the biggest consumers of the energy grid. The so-called “Green Datacentre” is capable of not only consuming but also producing power, thus becoming an important kind of prosumers in the electric grid. Green datacentres consist of a microgrid with a backup uninterrupted power supply and renewable generation, e.g., using photovoltaic panels. As such, datacentres could realistically be important participants in demand/response applications. However, this requires reconsidering their currently rigid control and automation systems and the use of simulation models for online estimation of the control actions impact. This paper presents such a microgrid simulation model modelled after a real edge datacentre. A case study consumption scenario is presented for the purpose of validating the developed microgrid model against data traces collected from the green edge datacentre. Both simulation and real-time validation tests are performed to validate the accuracy of the datacentre model. Then the model is connected to the automation environment to be used for the online impact estimation and virtual commissioning purposes.
8.	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.
9.	Behzadi, Amirmohammad, et al. (author) A Green and Energy-Efficient Smart Building Driven by Photovoltaic Thermal Panels Connected to the Grid 2023 In: International Conference on Smart Cities and Green ICT Systems, SMARTGREENS - Proceedings. - : Science and Technology Publications, Lda. - 9789897586514 ; , s. 106-112 Conference paper (peer-reviewed)abstract The present paper introduces a new smart building system driven by photovoltaic thermal panels. The concept is to improve the contribution of renewable energy in the local matrix for peak load shaving by having a two-way connection with the local electricity network via a rule-based energy monitoring control design. Besides, the feasibility of removing the electrical storage unit with high investment cost is studied by establishing a dynamic interaction between the energy production and usage components to reduce the energy costs over the year. The system has intelligent thermal energy storage integrated with an electrically-driven coil, heat exchanger, pumps, and several smart valves and control units. The transient system simulation (TRNSYS) package is implemented to assess the practicality of the suggested intelligent model for a building complex in Malmo, Sweden. According to the parametric outcomes, by raising the panel area, while the generated electricity increases, the solar utilization factor falls, indicating conflictive changes among performance metrics. The results also show that the renewable resource covers the building's heating and electricity demands for the majority of the year and that a significant amount of energy is sold to the neighbourhood electricity grid, demonstrating the viability of the introduced intelligent model.
10.	Lv, Zhihan, Dr. 1984-, et al. (author) Towards carbon Neutrality : Prediction of wave energy based on improved GRU in Maritime transportation 2023 In: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 331 Journal article (peer-reviewed)abstract Efficient use of renewable energy is one of the critical measures to achieve carbon neutrality. Countries have introduced policies to put carbon neutrality on the agenda to achieve relatively zero emissions of greenhouse gases and to cope with the crisis brought about by global warming. This work analyzes the wave energy with high energy density and wide distribution based on understanding of various renewable energy sources. This study provides a wave energy prediction model for energy harvesting. At the same time, the Gated Recurrent Unit network (GRU), Bayesian optimization algorithm, and attention mechanism are introduced to improve the model's performance. Bayesian optimization methods are used to optimize hyperparameters throughout the model training, and attention mechanisms are used to assign different weights to features to increase the prediction accuracy. Finally, the 1-hour and 6-hour forecasts are made using the data from China's NJI and BSG observatories, and the system performance is analyzed. The results show that, compared with mainstream prediction algorithms, GRU based on Bayesian optimization and attention mechanism has the highest prediction accuracy, with the lowest MAE of 0.3686 and 0.8204, and the highest R2 of 0.9127 and 0.6436, respectively. Therefore, the prediction model proposed here can provide support and reference for the navigation of ships powered by wave energy.
11.	Kersten, Anton, 1991 (author) Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges 2021 Doctoral thesis (other academic/artistic)abstract Modular battery systems based on multilevel inverter (MLI) topologies can possibly overcome some shortcomings of two-level inverters when used for vehicle propulsion. The results presented in this thesis aim to point out the advantages and disadvantages, as well as the technical challenges, of modular vehicle battery systems based on MLIs in comparison to a conventional, two-level IGBT inverter drivetrain. The considered key aspects for this comparative investigation are the drive cycle efficiency, the inverter cost, the fault tolerance capability of the drivetrain and the conducted electromagnetic emissions. Extensive experiments have been performed to support the results and conclusions. In this work, it is shown that the simulated drive cycle efficiency of different low-voltage-MOSFET-based, cascaded seven-level inverter types is improved in comparison to a similarly rated, two-level IGBT inverter drivetrain. For example, the simulated WLTP drive cycle efficiency of a cascaded double-H-bridge (CDHB) inverter drivetrain in comparison to a two-level IGBT inverter, when used in a small passenger car, is increased from 94.24% to 95.04%, considering the inverter and the ohmic battery losses. In contrast, the obtained efficiency of a similar rated seven-level cascaded H-bridge (CHB) drivetrain is almost equal to that of the two-level inverter drivetrain, but with the help of a hybrid modulation technique, utilizing fundamental selective harmonic elimination at lower speeds, it could be improved to 94.85%. In addition, the CDHB and CHB inverters’ cost, in comparison to the two-level inverter, is reduced from 342€ to 202€ and 121€, respectively. Furthermore, based on a simple three-level inverter with a dual battery pack, it is shown that MLIs inherently allow for a fault tolerant operation. It is explained how the drivetrain of a neutral point clamped (NPC) inverter can be operated under a fault condition, so that the vehicle can drive with a limited maximum power to the next service station, referred to as limp home mode. Especially, the detection and localization of open circuit faults has been investigated and verified through simulations and experiments. Moreover, it is explained how to measure the conducted emissions of an NPC inverter with a dual battery pack according to the governing standard, CISPR 25, because the additional neutral point connection forms a peculiar three-wire DC source. To separate the measured noise spectra into CM, line-DM and phase-DMquantities, two hardware separators based on HF transformers are developed and utilized. It is shown that the CM noise is dominant. Furthermore, the CM noise is reduced by 3dB to 6dB when operating the inverter with three-level instead of two-level modulation.
12.	PAPPIS, IOANNIS, 1989- (author) Trade-offs and conflicting objectives of decision-making investments in low-carbon technology portfolios for sustainable development : National and continental insights offered by applying energy system models 2022 Doctoral thesis (other academic/artistic)abstract Energy infrastructure and appropriate energy policies are crucial for sustainable development and to meet Sustainable Development Goals (SDGs). Limiting global warming potential below 1.5oC would require “rapid and far-reaching” transitions and unprecedented changes in all aspects of society. Several factors influence investment decisions on energy conversion technologies and their specific locations. The choice, timing, and location of energy investments affect the total system cost, socio-economic development, the environment (e.g., emissions, water use), and a nation's energy security. However, existing national energy modelling initiatives only investigate a subset of these pillars for achieving sustainability.This thesis examines the challenges associated with the energy transition of low-and middle-income countries (Paraguay, Ethiopia, Africa). This work considers national and global policies, focusing on achieving SDG7 and SDG13. The dissertation includes a cover essay and four appended papers. The research conducted in this Thesis examines how energy-systems models can assist in understanding an energy system's complex interactions for sustainable development.Specifically, the results highlight hydropower and solar PV as key technologies to achieve climate change targets, energy security and energy access goals. Hydropower and other renewable electricity can be exported to bolster energy security for the exporting country, although export revenues are eroded by local demand growth and low export prices. The benefits of low-cost electricity provided by cross-border hydropower should be balanced against energy security concerns for the importing country. The research demonstrates the benefits of regional coordination, with trade enabling renewable resources to be harnessed and the electricity transmitted to demand centres. Although RET decreases carbon dioxide emissions and water use compared to fossil-fuel plants and creates more jobs, they require high up-front capital costs offset by the lower operating fuel costs in the long term. Thus, increasing the ambition of climate targets while achieving electricity access results in lower cumulative costs. Also, although hydropower and renewable technologies build climate resilience, hydropower operation depends on climate variability affecting energy security. Thus, mitigation strategies should consider the associated challenges of climate change in hydropower investments.Hydropower and renewables are primarily grid-connected technologies, so off-grid and mini-grid systems are key complements to national-grid expansion when pushing for universal energy access. They also impact energy security, total system costs and socio-economic development. This Thesis's outcomes can support governments in strategic energy planning to identify future renewable energy projects and ensure their financial viability. Energy systems in their transition need to be affordable, reliable and sustainable (e.g., energy secured, combat climate change) by being climate-resilient. The thesis findings demonstrate that nations need integrated energy planning, accounting for the geospatial characteristics of energy technologies, and water resources management to achieve SDG7 and build climate-resilient (SDG13). A broad portfolio of renewable technologies, interconnectors and a decentralized power generation system providing electricity closer to the end-user demand is needed to enhance energy security, decrease environmental pressures and provide affordable electricity for a nation.
13.	Malmgren, Elin, 1992, et al. (author) The environmental performance of a fossil-free ship propulsion system with onboard carbon capture – a life cycle assessment of the HyMethShip concept 2021 In: Sustainable Energy & Fuels. - : Royal Society of Chemistry (RSC). - 2398-4902. ; 5:10, s. 2753-2770 Journal article (peer-reviewed)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.
14.	Garciá-Carmona, L., et al. (author) Biohybrid systems for environmental intelligence on living plants : WatchPlant project 2021 In: GoodIT 2021 - Proceedings of the 2021 Conference on Information Technology for Social Good. - New York, NY, USA : Association for Computing Machinery (ACM). ; , s. 210-215 Conference paper (peer-reviewed)abstract New challenges such as climate change and sustainability arise in society influencing not only environmental issues but human's health directly. To face these new challenges IT technologies and their application to environmental intelligent monitoring become into a powerful tool to set new policies and blueprints to contribute to social good. In the new H2020 project, WatchPlant will provide new tools for environmental intelligence monitoring by the use of plants as "well-being"sensors of the environment they inhabit. This will be possible by equipping plants with a net of communicated wireless self-powered sensors, coupled with artificial intelligence (AI) to become plants into "biohybrid organisms"to test exposure-effects links between plant and the environment. It will become plants into a new tool to be aware of the environment status in a very early stage towards in-situ monitoring. Additionally, the system is devoted to be sustainable and energy-efficient thanks to the use of clean energy sources such as solar cells and a enzymatic biofuel cell (BFC) together with its self-deployment, self-awareness, adaptation, artificial evolution and the AI capabilities. In this concept paper, WatchPlant will envision how to face this challenge by joining interdisciplinary efforts to access the plant sap for energy harvesting and sensing purposes and become plants into "biohybrid organisms"to benefit social good in terms of environmental monitoring in urban scenarios.
15.	Hasselqvist, Hanna, et al. (author) Exploring Renewable Energy Futures through Household Energy Resilience 2022 In: Conference on Human Factors in Computing Systems - Proceedings. - New York, NY, USA : Association for Computing Machinery. - 9781450391573 Conference paper (peer-reviewed)abstract A transition to renewable energy increases the risks of disruptions when electricity supply does not meet demand. HCI has explored how digital technologies can mitigate such problems in households through support for reducing or shifting electricity use. However, faster transitions may be possible if some disturbances can be acceptable and households are supported in adapting to them. In this paper, we present a study of 21 Swedish households and their experiences of and ideas on how to manage disruptions in electricity supply. We call this perspective household energy resilience and identify three strategies for resilience: (1) response diversity, i.e., diversity in ways of carrying out normally electricity-dependent practices, (2) creating opportunities to develop resilience, and (3) building community energy resilience. Furthermore, we suggest how HCI can support these strategies, both by providing tools to increase resilience and by carefully designing technology and services to be more resilient in themselves. © 2022 Owner/Author.
16.	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.
17.	Rendon, M. A., et al. (author) Energy management of a hybrid-electric aeronautical propulsion system to be used in a stationary test bench 2020 In: Proceedings of the ASME Turbo Expo. - : American Society of Mechanical Engineers (ASME). - 9780791884140 Conference paper (peer-reviewed)abstract Environmental requirements have led the air transportation industry to work towards reducing greenhouse gas emissions and mechanical noise levels. Nowadays, this sector contributes with 2% of the total greenhouse gas emissions, and there is a demand from global aviation regulators for further reducing this percentage. In the last years, the development of Hybrid-Electric Propulsion Systems (HEPSs) has grown. The HEPS combines an Internal Combustion Engine (ICE), for example, Gas Turbine (GT) or reciprocating engine, with an Electric Motor (EM), combining the inherent advantages of both. HEPSs present increased efficiency and operating safety in comparison with conventional ICE-powered systems. Furthermore, they can supply the electrical devices with power. This area of study is multidisciplinary in nature and, therefore, poses research challenges on ICEs, EMs, electronic converters, propeller design, monitoring and control systems, management and supervision systems, energy efficiency and optimization, aerodynamics and aircraft mechanical design. A research project aimed at the characterisation of hybrid-electric aircraft propulsion systems, and the construction of a HEPS prototype, is underway in Brazil. The system is essentially composed of a GT, an EM, three electronic converters, a battery bank and a propeller. It can operate with three different topologies: series, full-electric and turbo-electric. A test bench with all the necessary peripheral and analysis infrastructure is under construction. Present work aims to: (i) develop simplified models for all the test bench components, (ii) given a mission profile, show the results of an initial energy management computing code that determines the optimal hybridization strategy, and (iii) simulate various operating alternatives for the chosen mission profile. The results (i) highlight the impact of critical characteristics of the batteries on the HEPS performance, and (ii) demonstrate the application of the management code on optimizing the aircraft energy consumption for a given mission profile.
18.	Tillig, Fabian, 1984, et al. (author) Design, operation and analysis of wind-assisted cargo ships 2020 In: Ocean Engineering. - : Elsevier BV. - 0029-8018. ; 211:1, s. 1-23 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.
19.	Fachrizal, Reza, 1993-, et al. (author) Residential building with rooftop solar PV system, battery storage and electric vehicle charging : Environmental impact and energy matching assessments for a multi-family house in a Swedish city 2022 In: 21st Wind & Solar Integration Workshop (WIW 2022). - : The Institution of Engineering and Technology (IET). - 9781839538339 ; , s. 565-572 Conference paper (peer-reviewed)abstract In this paper, environmental impact and energy matching assessments for a residential building with a rooftop photovoltaic (PV)system, battery energy storage system (BESS) and electric vehicles (EV) charging load are conducted. This paper studies a real multi-family house with a rooftop PV system in a city located on the west-coast of Sweden, as a case study. The environmental impact parameter assessed in this study is CO2 equivalent (CO2-eq) emissions. It should be noted that the CO2-eqemission assessment takes into account the whole life cycle, not only the operational processes. The assessments consider boththe household and transport energy demands for the building’s residents. Results show that, CO2-eq emissions from the building electricity usage are increased by 1.65 ton/year with the integrationof PV-BESS system. This is because the Swedish electricity mix has a lower CO2-eq emissions than the PV-BESS system. The total CO2-eq emissions from the transport needs of the building’s residents are significantly decreased, by 32.9 ton/year, if they switch from fossil-fuel-powered cars to EVs. However, the integration of EVs increases the power demand significantly which could be problematic for the power system. In such scenario, the highly-utilized distributed PV systems, enhanced by BESS, can be a low-carbon solution to address the increased power demand challenges coming from transport electrification.
20.	Dreier, Dennis, et al. (author) Comparison of management strategies for the charging schedule and all-electric operation of a plug-in hybrid-electric bi-articulated bus fleet 2020 In: Public Transport. - : Springer Nature. - 1866-749X .- 1613-7159. ; 12:2, s. 363-404 Journal article (peer-reviewed)abstract This study developed a real-time optimisation (RTO) model that uses real-world bus operation data, i.e. route-specific and time-specific driving cycles. Potentials for energy savings and all-electric operation were estimated for a plug-in hybrid-electric bi-articulated bus fleet (PLUG scenario) that can be managed according to different management strategies. Five strategies A–E were simulated that manage the charging schedule and all-electric operation with different priorities: PLUG-A, prioritise buses for charging by arrival times at the charging station (“first come, first served”); PLUG-B, prioritise buses for charging by energy intensities of the bus routes; PLUG-C, minimise the total energy use of the bus fleet; PLUG-D, maximise the total all-electric time of the bus fleet; and PLUG-E, maximise the total all-electric distance of the bus fleet. For comparison, a business as usual (BAU) scenario with conventional buses and another scenario with hybrid-electric buses (HYB) were simulated. Two weeks of real-world bus operation data from the city of Curitiba in Brazil were used as input data. The study finds that total energy savings of 17% and 27% in the HYB and PLUG scenarios can be achieved compared to the BAU scenario, respectively. Meanwhile, the average shares of the total all-electric time (TAET) and total all-electric distance (TAED) to the total bus fleet operation amount to 20% and 14% in the HYB scenario. Furthermore, both TAET and TAED in the PLUG scenario depend strongly on the chosen strategy amounting to ranges of 21–64% and 17–61%, respectively. Simultaneous maxima were found for strategy D.
21.	Lv, Zhihan, Dr. 1984-, et al. (author) Digital twins for secure thermal energy storage in building 2023 In: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 338 Journal article (peer-reviewed)abstract The purpose of this work is to explore the role of the safe and optimal scheduling of thermal energy storage systems in intelligent buildings in promoting sustainable economic development under Digital Twins (DTs) technology. Phase Change Material (PCM) has high energy density, constant temperature storage, small footprint, and long service life. Here, PCM is first placed in the indoor building structure, and the DTs technology is introduced. In the development of intelligent buildings, the data generated by the energy storage system of intelligent buildings in the real space can be mapped to the virtual space in real time for simultaneous analysis. In addition, the PCM wall structure and thermal network DTs model are designed for the intelligent building. In addition, the PCW structure is used to build a thermal energy storage and dispatch model of the smart thermoelectric building based on DTs. Finally, the model is evaluated and analyzed experimentally. The analysis of system optimization power under different schemes indicates that the scheduling operation strategy of thermal energy storage of building walls can avoid overcharging or over-discharging batteries in the microgrid and reduce battery power consumption. Besides, the building wall energy storage capacity is always in the range of 0.2 ∼ 0.8 on the all-weather scale. Moreover, the model constructed here achieves significantly lower economic costs, environmental costs, and energy costs and a better energy-saving effect than the existing model. The model built here can serve as experimental reference for further digital energy storage in intelligent buildings and comprehensive energy utilization because of its superior safety performance and lower consumption.
22.	Mirzaei Alavijeh, Nima, 1993, et al. (author) Cost-Effectiveness of Carbon Emission Abatement Strategies for a Local Multi-Energy System - A Case Study of Chalmers University of Technology Campus 2020 In: Energies. - : MDPI AG. - 1996-1073 .- 1996-1073. ; 13:7 Journal article (peer-reviewed)abstract This paper investigates the cost-effectiveness of operation strategies which can be used to abate CO2 emissions in a local multi-energy system. A case study is carried out using data from a real energy system that integrates district heating, district cooling, and electricity networks at Chalmers University of Technology. Operation strategies are developed using a mixed integer linear programming multi-objective optimization model with a short foresight rolling horizon and a year of data. The cost-effectiveness of different strategies is evaluated across different carbon prices. The results provide insights into developing abatement strategies for local multi-energy systems that could be used by utilities, building owners, and authorities. The optimized abatement strategies include: increased usage of biomass boilers, substitution of district heating and absorption chillers with heat pumps, and higher utilization of storage units. The results show that, by utilizing all the strategies, a 20.8% emission reduction can be achieved with a 2.2% cost increase for the campus area. The emission abatement cost of all strategies is 36.6–100.2 (€/tCO2 ), which is aligned with estimated carbon prices if the Paris agreement target is to be achieved. It is higher, however, than average European Emission Trading System prices and Sweden’s carbon tax in 2019.
23.	Cowie, A. L., et al. (author) Applying a science-based systems perspective to dispel misconceptions about climate effects of forest bioenergy 2021 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.
24.	Heinisch, Verena, 1991, et al. (author) The impact of limited electricity connection capacity on energy transitions in cities 2021 In: Smart Energy. - : Elsevier BV. - 2666-9552. ; 3 Journal article (peer-reviewed)abstract We study the impacts of the connection capacity for electricity transfer between a city and a regional energy system on the design and operation of both systems. The city energy system is represented by the aggregate energy demand of three cities in southern Sweden, and the regional energy system is represented by Swedish electricity price area SE3. We minimize the investment and running costs in the electricity and district heating sectors, considering different levels of connection capacity between the city and the regional energy systems; connection capacities equal to 100%, 75%, 50% and 0% of the maximum city electricity demand. We find that a system design with 50% connection capacity is only 3% more expensive in terms of total costs than a system with 100% connection capacity. However, shifting electricity generation capacity from the regional to the city energy system with 50%, as compared to 100%, connection capacity leads to a higher marginal cost for electricity in the city than in the region. With the highest connection capacities, 75% and 100%, the district heating sector in the city can support wind power integration in the regional energy system by means of power-to-heat operation. Modeling systems with different connection capacities makes our results applicable to other fast-growing cities with potential to increase local electricity production and sector coupling between the electricity, district heating and electrified transport sectors.
25.	Engström, Rebecka Ericsdotter, 1984- (author) 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.

Skapa referenser, mejla, bekava och länka

Permalink

Träfflista för sökning "AMNE:(ENGINEERING AND TECHNOLOGY Environmental Engineering Energy Systems) srt2:(2020-2024)"

Refine your search

Year