1. |
- Chen, B., et al.
(author)
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Pathways for sustainable energy transition
- 2019
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In: Journal of Cleaner Production. - : Elsevier Ltd. - 0959-6526 .- 1879-1786. ; 228, s. 1564-1571
-
Journal article (peer-reviewed)abstract
- Energy transitions are ongoing processes all over the world. While sustainable solutions are envisioned for the future, many societies are still under high-carbon and high-pollution energy regime borne by fossil fuels. How to design pathways towards sustainable energy transition has attracted worldwide concerns. Understanding the possible transition pathways of the energy system requires the integration of new energy technologies, environmental sciences, economics and management. This Special Issue of Journal of Cleaner Production targets to collect the latest research results on sustainable energy systems, discover innovative avenues and inspiring models and share knowledge on energy system modelling and management. In this paper, we identify 4 themes on sustainable energy transition pathways including: (1)Sustainable energy economics and management; (2)Renewable energy generation and consumption; (3)Environmental impacts of energy systems; and (4)Electric vehicle and energy storage. Theories, technologies, innovative models, and successful experiences are discussed accordingly. It is suggested that creative, robust and audacious strategies in governance, management and education are needed to boost sustainable energy transition across various scales and sectors.
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2. |
- Gustafsson, Marcus, 1987-, et al.
(author)
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Techno-economic analysis of energy renovation measures for a district heated multi-family house
- 2016
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In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 177, s. 108-116
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Journal article (peer-reviewed)abstract
- Renovation of existing buildings is important in the work toward increased energy efficiency and reduced environmental impact. The present paper treats energy renovation measures for a Swedish district heated multi-family house, evaluated through dynamic simulation. Insulation of roof and façade, better insulating windows and flow-reducing water taps, in combination with different HVAC systems for recovery of heat from exhaust air, were assessed in terms of life cycle cost, discounted payback period, primary energy consumption, CO2 emissions and non-renewable energy consumption. The HVAC systems were based on the existing district heating substation and included mechanical ventilation with heat recovery and different configurations of exhaust air heat pump.Compared to a renovation without energy saving measures, the combination of new windows, insulation, flow-reducing taps and an exhaust air a heat pump gave up to 24% lower life cycle cost. Adding insulation on roof and façade, the primary energy consumption was reduced by up to 58%, CO2 emissions up to 65% and non-renewable energy consumption up to 56%. Ventilation with heat recovery also reduced the environmental impact but was not economically profitable in the studied cases. With a margin perspective on electricity consumption, the environmental impact of installing heat pumps or air heat recovery in district heated houses is increased. Low-temperature heating improved the seasonal performance factor of the heat pump by up to 11% and reduced the environmental impact.
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3. |
- Lindroth [formerly Tyrberg], Simon, 1979-
(author)
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Buoy and Generator Interaction with Ocean Waves : Studies of a Wave Energy Conversion System
- 2011
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Doctoral thesis (other academic/artistic)abstract
- On March 13th, 2006, the Division of Electricity at Uppsala University deployed its first wave energy converter, L1, in the ocean southwest of Lysekil. L1 consisted of a buoy at the surface, connected through a line to a linear generator on the seabed. Since the deployment, continuous investigations of how L1 works in the waves have been conducted, and several additional wave energy converters have been deployed. This thesis is based on ten publications, which focus on different aspects of the interaction between wave, buoy, and generator. In order to evaluate different measurement systems, the motion of the buoy was measured optically and using accelerometers, and compared to measurements of the motion of the movable part of the generator - the translator. These measurements were found to correlate well. Simulations of buoy and translator motion were found to match the measured values. The variation of performance of L1 with changing water levels, wave heights, and spectral shapes was also investigated. Performance is here defined as the ratio of absorbed power to incoming power. It was found that the performance decreases for large wave heights. This is in accordance with the theoretical predictions, since the area for which the stator and the translator overlap decreases for large translator motions. Shifting water levels were predicted to have the same effect, but this could not be seen as clearly. The width of the wave energy spectrum has been proposed by some as a factor that also affects the performance of a wave energy converter, for a set wave height and period. Therefore the relation between performance and several different parameters for spectral width was investigated. It was found that some of the parameters were in fact correlated to performance, but that the correlation was not very strong. As a background on ocean measurements in wave energy, a thorough literature review was conducted. It turns out that the Lysekil project is one of quite few projects that have published descriptions of on-site wave energy measurements.
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4. |
- Thomas, Jean-Baptiste, et al.
(author)
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A comparative environmental life cycle assessment of hatchery, cultivation, and preservation of the kelp Saccharina latissima
- 2021
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In: Ices Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 78:1, s. 451-467
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Journal article (peer-reviewed)abstract
- Seaweed cultivation and processing industries could contribute to sustainable blue growth and the European bioeconomy. This article contributes a case study evaluation of environmental sustainability of preserved brown seaweed Saccharina latissima by means of environmental life cycle assessment of a pilot facility in Sweden. The study accounts for nutrient bioremediation and carbon capture and includes two alternative hatchery processes, a 2-ha longline cultivation, and four alternative preservation methods (hang-drying outdoors, heated air-cabinet drying, ensiling, and freezing). The study found that as a result of carbon capture and nitrogen and phosphorus uptake (bioremediation) by seaweed, more CO2 and PO4 equivalents are (temporarily) absorbed than emitted by the supply chain. The extent of emissions is most affected by preservation methods undertaken. Impact profiles of the supply chain show that the greatest impact shares result from freezing and air-cabinet drying, both the two most energy-intensive processes, followed by the cultivation infrastructure, highlighting strategic optimization opportunities. Hatchery processes, harvesting, and the low-energy ensilage and hang-drying outdoors were found to have relatively small impact shares. These findings presage the environmentally friendliness of seaweed-based products by documenting their potential to mitigate eutrophication and climate change, even when taking a life cycle perspective.
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5. |
- Mathern, Alexandre, 1986, et al.
(author)
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Concrete Support Structures for Offshore Wind Turbines: Current Status, Challenges, and Future Trends
- 2021
-
In: Energies. - : MDPI AG. - 1996-1073 .- 1996-1073. ; 14:7
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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.
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6. |
- Herre, Lars, 1990-, et al.
(author)
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Simplified model of integrated paper mill for optimal bidding in energy and reserve markets
- 2020
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In: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 279
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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.
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7. |
- Svensson, Olle, 1967-
(author)
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Experimental results from the Lysekil Wave Power Research Site
- 2012
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Doctoral thesis (other academic/artistic)abstract
- This thesis presents how experimental results, from wave power research performed offshore at the Lysekil research site, were obtained. The data were used to verify theoretical models as well as evaluate the feasibility of wave power as a future sustainable energy source.The first experiments carried out at the research site was the measurement of the force in a line where one end was connected to a buoy with a diameter of 3 m and the other end to a set of springs with limited stroke length. The system is exposed to high peak forces compared to average forces. The maximum measured force in the line, when the buoy motion is limited by a stiff stopper rope is ten times the average force in that particular sea state.The experiment performed on the first wave energy converter tested at the Lysekil Research Site is described. The infrastructure of the site is presented where the central connection point is the measuring station. The key finding is that it is possible to transform the motions of ocean waves into electrical energy and distribute it to land.Many wave energy converters must be interconnected if large amounts of energy are to be harvested from the waves. The first submerged substation intended for aggregation of energy from wave power converters is described, with focus on the measurement and control system placed inside the substation. During this experiment period the generators were equipped with many different sensors; these measurements are explained in the thesis.The system that aggregates power from the studied wave energy converter is regularly exposed to peak power of up to 20 times the maximum average output from the converter.Vertical and horizontal movement of the buoy has been measured in different ways. The result is that the vertical displacement of the buoy can be measured with a simple accelerometer circuit but it is much more complicated to measure the horizontal displacement. A special method for measuring the horizontal displacement has been implemented by measuring the strain in the enclosure and the force in the line.
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8. |
- Johansson, Björn, 1975, et al.
(author)
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Power Level Sampling of Metal Cutting Machines for Data Representation in Discrete Event Simulation
- 2015
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In: International Journal of Production Research. - : Informa UK Limited. - 0020-7543 .- 1366-588X. ; 53:23, s. 7060-7070
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Journal article (peer-reviewed)abstract
- An extension to the application area for discrete event simulation (DES) has been ongoing since the last decade and focused only on economic aspects to include ecologic sustainability. With this new focus, additional input parameters, such as electrical power consumption of machines, are needed. This paper aim at investigating how NC machine power consumption should be represented in simulation models of factories. The study includes data-sets from three different factories. One factory producing truck engine blocks, one producing brake disc parts for cars and one producing forklift components. The total number of data points analysed are more than 2,45,000, where of over 1,11,000 on busy state for 11 NC machines. The low variability between busy cycles indicates that statistical representations are not adding significant variability. Furthermore, results show that non-value-added activities cause a substantial amount of the total energy consumption, which can be reduced by optimising the production flow using dynamic simulations such as DES.
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9. |
- 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.
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10. |
- Lindahl, Niklas, 1981, et al.
(author)
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Early stage techno-economic and environmental analysis of aluminium batteries
- 2023
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In: Energy Advances. - : Royal Society of Chemistry (RSC). - 2753-1457. ; 2:3, s. 420-429
-
Journal article (peer-reviewed)abstract
- For any proper evaluation of next generation energy storage systems technological, economic, and environmental performance metrics should be considered. Here conceptual cells and systems are designed for different aluminium battery (AlB) concepts, including both active and passive materials. Despite the fact that all AlBs use high-capacity metal anodes and materials with low cost and environmental impact, their energy densities differ vastly and only a few concepts become competitive taking all aspects into account. Notably, AlBs with high-performance inorganic cathodes have the potential to exhibit superior technological and environmental performance, should they be more reversible and energy efficient, while at the system level costs become comparable or slightly higher than for both AlBs with organic cathodes and lithium-ion batteries (LIBs). Overall, with continued development, AlBs should be able to complement LIBs, especially in light of their significantly lower demand for scarce materials. Several aluminium battery concepts are evaluated at material, cell and system levels for technical, economic and environmental performance, which enables them to complement lithium-ion batteries in the future.
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11. |
- 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.
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12. |
- Galkin, Nikolai, et al.
(author)
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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.
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13. |
- Zhang, Yang, et al.
(author)
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Planning and operation of an integrated energy system in a Swedish building
- 2019
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In: Energy Conversion and Management. - : Elsevier. - 0196-8904 .- 1879-2227. ; 199
-
Journal article (peer-reviewed)abstract
- More flexibility measures are required due to the increasing capacities of variable renewable energies (VRE). In buildings, the integration of energy supplies forms integrated energy systems (IES). IESs can provide flexibility and increase the VRE penetration level. To upgrade a current building energy system into an IES, several energy conversion and storage components are needed. How to decide the component capacities and operate the IES were investigated separately in studies on system planning and system operation. However, a research gap exists that the system configuration from system planning is not validated by actual operation conditions in system operation. Meanwhile, studies on system operation assume that IES configurations are predetermined. This work combines system planning and system operation. The IES configuration is determined by mixed integer linear programming in system planning. Actual operation conditions and forecast errors are considered in system operation. The actual operation profiles are obtained through year-round simulations of different energy management systems. The results indicate that the system configuration from system planning can meet energy demands in system operation. Among different energy management systems, the combination of robust optimization and receding horizon optimization achieves the lowest yearly operation cost. Meanwhile, two scenarios that represent high and low forecast accuracies are studied. Under the high and low forecast accuracy scenarios, the yearly operation costs are about 4% and 6% higher than that obtained from system planning.
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14. |
- Shahroozi, Zahra, 1992-
(author)
-
Survivability control using data-driven approaches and reliability analysis for wave energy converters
- 2024
-
Doctoral thesis (other academic/artistic)abstract
- Wave energy, with five times the energy density of wind and ten times the power density of solar, offers a compelling carbon-free electricity solution. Despite its advantages, ongoing debates surround the reliability and economic feasibility of wave energy converters (WECs). To address these challenges, this doctoral thesis is divided into four integral parts, focusing on optimizing the prediction horizon for power maximization, analyzing extreme waves' impact on system dynamics, ensuring reliability, and enhancing survivability in WECs.Part I emphasizes the critical importance of the prediction horizon for maximal power absorption in wave energy conversion. Using generic body shapes and modes, it explores the effect of dissipative losses, noise, filtering, amplitude constraints, and real-world wave parameters on the prediction horizon. Findings suggest achieving optimal power output may be possible with a relatively short prediction horizon, challenging traditional assumptions.Part II shifts focus to WEC system dynamics, analyzing extreme load scenarios. Based on a 1:30 scaled wave tank experiment, it establishes a robust experimental foundation, extending into numerical assessment of the WEC. Results underscore the importance of damping to alleviate peak forces. Investigating various wave representations highlights conservative characteristics of irregular waves, crucial for WEC design in extreme sea conditions.Part III explores the computational intricacies of environmental design load cases and fatigue analyses for critical mechanical components of the WEC. The analysis is conducted for hourly sea state damage and equivalent two-million-cycle loads. Finally, a comparison of safety factors between the ultimate limit state and fatigue limit state unfolds, illustrating the predominant influence of the ultimate limit state on point-absorber WEC design.Part IV, centers on elevating survivability strategies for WECs in extreme wave conditions. Three distinct controller system approaches leverage neural networks to predict and minimize the line force. Distinct variations emerge in each approach, spanning from rapid detection of optimal damping to integrating advanced neural network architectures into the control system with feedback. The incorporation of a controller system, refined through experimental data, showcases decreases in the line force, providing a practical mechanism for real-time force alleviation.This thesis aims to contribute uniquely to the goal of advancing wave energy conversion technology through extensive exploration.
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15. |
- Behzadi, Amirmohammad, et al.
(author)
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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.
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16. |
- Lv, Zhihan, Dr. 1984-, et al.
(author)
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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.
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17. |
- 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.
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18. |
- Ghaviha, Nima, et al.
(author)
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Review of Application of Energy Storage Devices in Railway Transportation
- 2017
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In: Energy Procedia. - : Elsevier BV. - 1876-6102.
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Conference paper (peer-reviewed)abstract
- Regenerative braking is one of the main reasons behind the high levels of energy efficiency achieved in railway electric traction systems. During regenerative braking, the traction motor acts as a generator and restores part of the kinetic energy into electrical energy. To use this energy, it should be either fed back to the power grid or stored on an energy storage system for later use. This paper reviews the application of energy storage devices used in railway systems for increasing the effectiveness of regenerative brakes. Three main storage devices are reviewed in this paper: batteries, supercapacitors and flywheels. Furthermore, two main challenges in application of energy storage systems are briefly discussed. © 2017 The Authors.
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19. |
- Rusu, Cristina, et al.
(author)
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Challenges for Miniaturised Energy Harvesting Sensor Systems
- 2018
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In: 2018 10th International Conference on Advanced Infocomm Technology (ICAIT). - : Institute of Electrical and Electronics Engineers Inc.. - 9781538679364 ; , s. 214-217
-
Conference paper (peer-reviewed)
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20. |
-
Chalmers Environmental Initiative Progress Report 2001
- 2001
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Editorial collection (peer-reviewed)abstract
- The Board of the Chalmers University of TechnologyFoundation decided in 1999 to invest SEK 100million in a strategic investment in the environmentwith a special focus on environmental systems analysis.This investment was entitled The ChalmersEnvironmental Initiative (CEI). Through thisenvironmental initiative Chalmers has acquired aprominent international position within environmentalsystems analysis.CEI is the result of the active research and educationthat has taken place at Chalmers over the past 10years. A broad base in combination with leadingedge technology presented the opportunity to createa very strong research programme based oninteraction between the various schools at Chalmers.As CEI is integrated into undergraduate anddoctoral programmes at Chalmers, engineers,architects and doctoral students have access, withinthe framework of their studies, to research-basedenvironmental education with a focus on asustainable society. CEI also co-operates with otherparties, such as industry, politicians, various organisationsand the general public, as a further means ofcontributing to sustainable development in society.Within CEI, seven new professors have beenappointed within the following areas:Management for SustainabilityRolf Wolff, 1 June 2000Environmental Systems TechnologyAnne-Marie Tillman, 1 September 2000Sustainable Industrial MetabolismChristian Azar, 1 September 2000Global Environmental MeasurementsDonal Murtagh, 1 November 2000Green ChemistryWilliam J. Frederick Jr, 1 August 2001Sustainable Energy SystemsFilip Johnsson, preliminary 1 October 2001Design for Sustainable Urban DevelopmentVacant: interviews during April 2001The four professors appointed in 2000 are presentedin this report as well as their declaration of intentfor the next few years. At present, the CEI professorsare involved with approximately 40 universities,institutes and industrial partners in the form ofproject co-operation and joint publications. The fourprofessors have the greater proportion of theirenvironmental research funded through externalgrants, compared to CEI. The proportion of facultyfunds and other internal Chalmers funds is at presentvery low. A summary of the financing structureis also included in this report.During 2001, various forms of co-operation wereinitiated between the professors, such as joint projectplans, doctoral students, courses and graduateschools. During autumn 2001, a residential seminaris planned for discussions within CEI as well as anopen presentation of the project and the professors.This major in-house focus on environmental researchhas attracted attention externally and contributedto the opening up of new potential in combinationwith increased expectations. Since May 1, 2000,Chalmers has been a member of the Alliance forGlobal Sustainability (AGS), an association of someof the world’s foremost universities in theenvironmental field. AGS and other platforms formthe basis for international research collaboration.CEI and other environmental activities have led tospin-off effects and contributed to increased interestin Chalmers as an environmental university.Chalmers and Göteborg University were, forexample, jointly awarded the King Carl XVI Gustafvisiting professorship in environmental science for2001-2002 and Margot Wallström received anhonorary doctorate from Chalmers in 2001. A largenumber of well-known environmental researchershave also visited Chalmers to take part inconferences and seminars, including the winners ofthe Volvo Environmental Award for 2000 and thewinner of the City of Göteborg InternationalEnvironmental Award for 2000.
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21. |
- PAPPIS, IOANNIS, 1989-
(author)
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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
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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.
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22. |
- Malmgren, Elin, 1992, et al.
(author)
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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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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.
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23. |
- Timmons, D., et al.
(author)
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Cost minimization for fully renewable electricity systems : A Mauritius case study
- 2019
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In: Energy Policy. - : Elsevier Ltd. - 0301-4215 .- 1873-6777. ; 133
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Journal article (peer-reviewed)abstract
- Climate change is the world's most prominent environmental problem, and fossil-fuel combustion is its primary cause. To set carbon reduction goals, policy makers require information on feasibility and cost of renewable energy systems. In this study, we describe an economic approach to modeling a national electricity system based entirely on renewable sources, using the island-nation of Mauritius as a case study. Many renewable electricity studies consider levelized costs of electricity (LCOE), which represents average cost of electricity, but cost minimization requires equalizing marginal costs. With variable sources, marginal costs change over time. Minimizing cost thus requires a model incorporating variability at high time resolution (daily or hourly), with the objective of minimizing the levelized cost of electricity for an entire electricity system (LCOES). In Mauritius, the minimum-cost renewable electricity portfolio includes roughly equal proportions of solar, wind, and biomass electricity, along with electricity storage. Policy issues include setting renewable energy targets, selecting policy instruments to incentivize optimum renewable energy portfolios, incorporating energy efficiency, determining appropriate discount rates, ensuring land availability, and accounting for non-cost considerations. Many of the economic and policy issues identified apply universally, and methods demonstrated in this study could be used anywhere in the world.
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24. |
- Garciá-Carmona, L., et al.
(author)
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Biohybrid systems for environmental intelligence on living plants : WatchPlant project
- 2021
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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.
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25. |
- Ringsberg, Jonas, 1971, et al.
(author)
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Comparison of mooring solutions and array systems for point absorbing wave energy devices
- 2018
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In: Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE. - 9780791851326 ; 11A, s. 1-11
-
Conference paper (peer-reviewed)abstract
- Most of the ocean energy technologies are considered to be ina pre-commercial phase and need technical development. Thisstudy focuses on design of mooring solutions and comparesarray systems of a specific floating point-absorbing waveenergy converter (WEC) developed by the companyWaves4Power. A full-scale prototype of the WEC is installedin Runde (Norway) where it is moored with three polyestermooring lines, each having one floater and one gravity anchor.Based on this reference installation, the method of systemsengineering was used to propose twenty-two conceptualmooring solutions for different array systems. They werecompared and reduced to four top concepts in a systematicelimination procedure using Pugh and Kesselring matrices. Thetop concepts were assessed in detail by means of LCOE(levelised cost of energy), LCA (life cycle analysis) and riskanalyses. The fatigue life of the mooring lines and the energycapture were calculated using results obtained from coupledhydrodynamic and structure response analyses in the DNV-GLDeepC software. Two final concepts were proposed for thewater depths 75 and 200 m.
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26. |
- De Castro Marins, Karin Regina
(author)
-
Balanced assessment of energy systems : Integrating energy usage & supply
- 2006
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In: PLEA - Int. Conf. Passive Low Energy Archit., Conf. Proc.. ; , s. II189-II194
-
Conference paper (peer-reviewed)abstract
- The present topic approaches energy systems, building and urban design in an integrated path. The objective of the project was to develop a methodology for balanced assessment of energy systems, considering two main pillars: Energy Usage and Energy Supply. Load management, cost, and environmental impact are analysed in order to identify a better overall performance, by the combination of initiatives in both sides. The research includes, in the energy usage side, design and management strategies for energy efficiency in residential and commercial buildings, and in urban planning as well. In the energy supply side, it includes decentralised systems in building scale, and centralised systems in neighbourhood and city scale. Electricity, space heating, and space cooling are considered. A quantitative assessment module and graphical interfaces were developed to support project development and decision-making, and demonstrate advantages of integrated approaches. A study-case was performed, corresponding to a master plan for urban development of the city of Miyun, in China, supposed to be a model of sustainable development. The project strongly emphasizes the need for relationship of dependent variables included in the design and management of city, building and energy systems, aiming to contribute to a more mature approach towards sustainability.
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27. |
- Wang, S., et al.
(author)
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Operational reliability of multi-energy customers considering service-based self-scheduling
- 2019
-
In: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 254
-
Journal article (peer-reviewed)abstract
- The developments of energy storage and substitution techniques have made it possible for customers to self-schedule their energy consumption behaviors, to better satisfy their demands in response to uncertain supply conditions. The interdependency of multiple energies, the chronological characteristics, and uncertainties in the self-scheduling context bring about additional complexities to secure the reliable energy requirements of multi-energy customers. As a necessary and challenging task, the operational reliability of multi-energy customers is tackled in this paper. Considering that the consumed energies eventually come down to the energy-related services, the self-scheduling of multi-energy customers is implemented from the perspective of specific energy-related services rather than energy carriers. Firstly, an optimal self-scheduling model for multi-energy customers is developed with the consideration of chronological service curtailment, service shifting and possible failures during service shifting. In the optimal self-scheduling model, the costs of service curtailment and shifting are formulated based on the proposed evaluation method. The time-sequential Monte Carlo simulation approach is applied to model the chronological volatilities of multi-energy demands over the entire study period, embedded with a scenario reduction technique to reduce the computational efforts. Taking full account of the possible scenarios, the quantitative reliability indices of the multi-energy customers can be obtained. The results in test cases demonstrate that the expected energy not supplied of the multi-energy customer drops significantly by 56.32% with the self-scheduling strategy. It can be also concluded that, the self-scheduling and its inherent uncertainties do have significant impacts on the operational reliability of the multi-energy customer.
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28. |
- Acuña, José, 1982-
(author)
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Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes
- 2013
-
Artistic work (other academic/artistic)abstract
- U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs.Field tests are performed using distributed temperature measurements along U-pipe and coaxial heat exchangers installed in groundwater filled boreholes. The measurements are carried out during heat injection thermal response tests and during short heat extraction periods using heat pumps. Temperatures are measured inside the secondary fluid path, in the groundwater, and at the borehole wall. These type of temperature measurements were until now missing.A new method for testing borehole heat exchangers, Distributed Thermal Response Test (DTRT), has been proposed and demonstrated in U-pipe, pipe-in-pipe, and multi-pipe BHE designs. The method allows the quantification of the BHE performance at a local level.The operation of a U-pipe thermosyphon BHE consisting of an insulated down-comer and a larger riser pipe using CO2 as a secondary fluid has been demonstrated in a groundwater filled borehole, 70 m deep. It was found that the CO2 may be sub-cooled at the bottom and that it flows upwards through the riser in liquid state until about 30 m depth, where it starts to evaporate.Various power levels and different volumetric flow rates have been imposed to the tested BHEs and used to calculate local ground thermal conductivities and thermal resistances. The local ground thermal conductivities, preferably evaluated at thermal recovery conditions during DTRTs, were found to vary with depth. Local and effective borehole thermal resistances in most heat exchangers have been calculated, and their differences have been discussed in an effort to suggest better methods for interpretation of data from field tests.Large thermal shunt flow between down- and up-going flow channels was identified in all heat exchanger types, particularly at low volumetric flow rates, except in a multi-pipe BHE having an insulated central pipe where the thermal contact between down- and up-coming fluid was almost eliminated.At relatively high volumetric flow rates, U-pipe BHEs show a nearly even distribution of the heat transfer between the ground and the secondary fluid along the depth. The same applies to all coaxial BHEs as long as the flow travels downwards through the central pipe. In the opposite flow direction, an uneven power distribution was measured in multi-chamber and multi-pipe BHEs.Pipe-in-pipe and multi-pipe coaxial heat exchangers show significantly lower local borehole resistances than U-pipes, ranging in average between 0.015 and 0.040 Km/W. These heat exchangers can significantly decrease the temperature difference between the secondary fluid and the ground and may allow the use of plain water as secondary fluid, an alternative to typical antifreeze aqueous solutions. The latter was demonstrated in a pipe-in-pipe BHE having an effective resistance of about 0.030 Km/W.Forced convection in the groundwater achieved by injecting nitrogen bubbles was found to reduce the local thermal resistance in U-pipe BHEs by about 30% during heat injection conditions. The temperatures inside the groundwater are homogenized while injecting the N2, and no radial temperature gradients are then identified. The fluid to groundwater thermal resistance during forced convection was measured to be 0.036 Km/W. This resistance varied between this value and 0.072 Km/W during natural convection conditions in the groundwater, being highest during heat pump operation at temperatures close to the water density maximum.
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29. |
- Hasselqvist, Hanna, et al.
(author)
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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.
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30. |
- Chiu, Justin N. W., et al.
(author)
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Industrial surplus heat storage in smart cities
- 2015
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In: ASME 2015 9th International Conference on Energy Sustainability, ES 2015, collocated with the ASME 2015 Power Conference, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. - : American Society of Mechanical Engineers. - 9780791856857
-
Conference paper (peer-reviewed)abstract
- Surplus heat generated from industrial sectors amounts to between 20% and 50% of the total industrial energy input. Smart reuse of surplus heat resulted from industrial sectors and power generation companies is an opportunity to improve the overall energy efficiency through more efficient use the primary energy sources. A potential solution to tackle this issue is through use of thermal energy storage (TES) to match user demand to that of the generated surplus heat. A mobile TES (MTES) concept of transportation of industrial surplus heat from production sites to end customers has shown promising results. One commissioned demonstration project using industrial heat for swimming pool water temperature regulation in Dortmund, Germany proved the interest and attention given to this concept. In this paper, a techno-economic case study in Sweden of transportation of surplus thermal energy to district heating in smart cities is presented. The application consists of heat storage at 110°C- 130°C through the use of phase change materials (PCM) based TES, notably with use of Erythritol (90 kWh/ton) for the considered temperature range, to remote district heating network located at 48 km from the thermal energy generation site. The advantages of using latent heat based PCM are the high enthalpy density per unit volume and per unit mass, as well as the quasi-constant temperature during charging and releasing of heat. The M-TES in this study has a total storage capacity of 2.1 MWh, the optimization of charge/discharge time to the amount of stored/released energy and to that of energy transportation rate is presented in this paper. Contrary to logical thinking, it is shown through this work that under certain conditions, it is more cost-effective to operate at partial load of storage units albeit the increased number of transport trips and charge/discharge cycles.
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31. |
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32. |
- Skagestad, Ragnhild, 1978, et al.
(author)
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GCCSI Webinar: Cutting Cost of CO2 Capture in Process Industry (CO2stCap) Project overview & first results for partial CO2 capture at integrated steelworks
- 2017
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Other publication (other academic/artistic)abstract
- GCCSI Webinar: Cutting Cost of CO2 Capture in Process Industry (CO2stCap) Project overview & first results for partial CO2 capture at integrated steelworks This publication has the format of a webinar: The CO2StCap project is a four year initiative carried out by industry and academic partners with the aim of reducing capture costs from CO2 intensive industries (more information here). The project, led by Tel-Tek, is based on the idea that cost reduction is possible by capturing only a share of the CO2 emissions from a given facility, instead of striving for maximized capture rates. This can be done in multiple ways, for instance by capturing only from the largest CO2 sources at individual multi-stack sites utilising cheap waste heat or adapting the capture volumes to seasonal changes in operations. The main focus of this research is to perform techno-economic analyses for multiple partial CO2 capture concepts in order to identify economic optimums between cost and volumes captured. In total for four different case studies are developed for cement, iron & steel, pulp & paper and ferroalloys industries. The first part of the webinar gave an overview of the project with insights into the cost estimation method used. The second part presented the iron & steel industry case study based on the Lulea site in Sweden, for which waste-heat mapping methodology has been used to assess the potential for partial capture via MEA-absorption. Capture costs for different CO2 sources were discussed, demonstrating the viability of partial capture in an integrated steelworks.
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33. |
- Englund, Oskar, 1982, et al.
(author)
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Large-scale deployment of grass in crop rotations as a multifunctional climate mitigation strategy
- 2023
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In: GCB Bioenergy. - : Wiley. - 1757-1707 .- 1757-1693. ; 15:2, s. 166-184
-
Journal article (peer-reviewed)abstract
- The agriculture sector can contribute to climate change mitigation by reducing its own greenhouse gas (GHG) emissions, sequestering carbon in vegetation and soils, and providing biomass to substitute for fossil fuels and other GHG-intensive products. The sector also needs to address water, soil, and biodiversity impacts caused by historic and current practices. Emerging EU policies create incentives for cultivation of perennial plants that provide biomass along with environmental benefits. One such option, common in northern Europe, is to include grass in rotations with annual crops to provide biomass while remediating soil organic carbon (SOC) losses and other environmental impacts. Here, we apply a spatially explicit model on >81,000 sub-watersheds in EU27 + UK (Europe) to explore the effects of widespread deployment of such systems. Based on current accumulated SOC losses in individual sub-watersheds, the model identifies and quantifies suitable areas for increased grass cultivation and corresponding biomass- and protein supply, SOC sequestration, and reductions in nitrogen emissions to water as well as wind and water erosion. The model also provides information about possible flood mitigation. The results indicate a substantial climate mitigation potential, with combined annual GHG savings from soil-carbon sequestration and displacement of natural gas with biogas from grass-based biorefineries, equivalent to 13%–48% of current GHG emissions from agriculture in Europe. The environmental co-benefits are also notable, in some cases exceeding the estimated mitigation needs. Yield increases for annual crops in modified rotations mitigate the displacement effect of increasing grass cultivation. If the grass is used as feedstock in lieu of annual crops, the displacement effect can even be negative, that is, a reduced need for annual crop production elsewhere. Incentivizing widespread deployment will require supportive policy measures as well as new uses of grass biomass, for example, as feedstock for green biorefineries producing protein concentrate, biofuels, and other bio-based products.
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34. |
- Rendon, M. A., et al.
(author)
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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.
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35. |
- Davidsson, Simon, et al.
(author)
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A review of life cycle assessments on wind energy systems
- 2012
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In: The International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 0948-3349 .- 1614-7502. ; 17:6, s. 729-742
-
Research review (peer-reviewed)abstract
- PurposeSeveral life cycle assessments (LCA) of wind energy published in recent years are reviewed to identify methodological differences and underlying assumptions.MethodsA full comparative analysis of 12 studies were undertaken (10 peer-reviewed papers, 1 conference paper, 1 industry report) regarding six fundamental factors (methods used, energy use accounting, quantification of energy production, energy performance and primary energy, natural resources, and recycling). Each factor is discussed in detail to highlight strengths and shortcomings of various approaches.ResultsSeveral potential issues are found concerning the way LCA methods are used for assessing energy performance and environmental impact of wind energy, as well as dealing with natural resource use and depletion. The potential to evaluate natural resource use and depletion impacts from wind energy appears to be poorly exploited or elaborated on in the reviewed studies. Estimations of energy performance and environmental impacts are critically analyzed and found to differ significantly.Conclusions and recommendationsA continued discussion and development of LCA methodology for wind energy and other energy resources are encouraged. Efforts should be made to standardize methods and calculations. Inconsistent use of terminology and concepts among the analyzed studies are found and should be remedied. Different methods are generally used and the results are presented in diverse ways, making it hard to compare studies with each other, but also with other renewable energy sources.
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36. |
- Tillig, Fabian, 1984, et al.
(author)
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Design, operation and analysis of wind-assisted cargo ships
- 2020
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In: Ocean Engineering. - : Elsevier BV. - 0029-8018. ; 211:1, s. 1-23
-
Journal article (peer-reviewed)abstract
- This study presents a novel approach to analytically capture aero- and hydrodynamic interaction effects on wind-assisted ships. Low aspect ratio wing theory is applied and modified to be used for the prediction of lift and drag forces of hulls sailing at drift angles. Aerodynamic interaction effects are captured by analytically solving the Navier-Stokes equation for incompressible, potential flow. The developed methods are implemented to a 4 degrees-of-freedom performance prediction model called “ShipCLEAN”, including a newly developed method for rpm control of Flettner rotors on a ship to maximize fuel savings. The accuracy of the model is proven by model- and full-scale verification. To present the variability of the model, two case study ships, a tanker and a RoRo, are equipped with a total of 11 different arrangements of Flettner rotors. The fuel savings and payback times are assessed using realistic weather from ships traveling on a Pacific Ocean route (tanker) and Baltic Sea route (RoRo). The results verify the importance of using a 4 degrees-of-freedom ship performance model, aero- and hydrodynamic interaction and the importance of controlling the rpm of each rotor individually. Fuel savings of 30% are achieved for the tanker, and 14% are achieved for the RoRo.
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37. |
- Shivakumar, Abhishek, et al.
(author)
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Drivers of renewable energy deployment in the EU : An analysis of past trends and projections
- 2019
-
In: Energy Strategy Reviews. - : Elsevier. - 2211-467X .- 2211-4688. ; 26
-
Journal article (peer-reviewed)abstract
- Energy policy in the European Union (EU) is driven by the objective to transition to an affordable, reliable, and low carbon energy system. To achieve this objective, the EU has explicitly stated targets for greenhouse reduction, shares of renewable energy sources (RES), and energy efficiency improvements for 2020 and 2030. In this paper, we focus on the drivers, barriers and enablers to achieving the EU's RES targets (20% by 2020 and 27% by 2030). Effective energy policies play a key role in the deployment of RES technologies. In order to design effective policies, a clear understanding of past trends and projections for future deployment is required. In this paper, we first analyse the past deployment of RES technologies for electricity supply (RES-E) in selected EU Member States. This highlights the key drivers, barriers, and enablers for deployment of RES in the past. In a second step, we conduct a meta-analysis of projections for RES-E shares from multiple well-established studies. Such an analysis will help in supporting the design of more effective energy policies and successfully achieving the EU's energy targets.
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38. |
- Fachrizal, Reza, 1993-, et al.
(author)
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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.
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39. |
- Dreier, Dennis, et al.
(author)
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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.
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40. |
- Lv, Zhihan, Dr. 1984-, et al.
(author)
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Digital twins for secure thermal energy storage in building
- 2023
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In: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 338
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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.
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41. |
- Mirzaei Alavijeh, Nima, 1993, et al.
(author)
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Cost-Effectiveness of Carbon Emission Abatement Strategies for a Local Multi-Energy System - A Case Study of Chalmers University of Technology Campus
- 2020
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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.
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42. |
- 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.
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43. |
- Heinisch, Verena, 1991, et al.
(author)
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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.
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44. |
- Karlsson, Åsa, et al.
(author)
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External Costs and Taxes in Heat Supply System
- 2003
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In: Energy Policy. - 0301-4215 .- 1873-6777. ; 31:14, s. 1541-1560
-
Journal article (peer-reviewed)abstract
- A systems approach was used to compare different heating systems from a consumer perspective. The whole energy system was considered from natural resources to the required energy services. District heating, electric heat pumps, electric boilers, natural-gas-, oil- or pellet-fired local boilers were considered when supplying heat to a detached house. The district heat production included wood-chip-fired and natural-gas-fired cogeneration plants. Electricity other than cogenerated electricity was produced in wood-chip- and natural-gas-fired stand-alone power plants. The analysis includes four tax scenarios, as well as the external cost of environmental and health damage arising from energy conversion emission based on the ExternE study of the European Commission. The most cost efficient systems were the natural-gas and oil boiler systems, followed by the heat pump and district heating systems, when the external cost and taxes were excluded. When including the external costs of CO2 emission, the wood-fuel-based systems were much more cost efficient than the fossil-fuel-based systems, also when CO2 capture and storage were applied. The external costs are, however, highly uncertain. Taxes steer towards lowering energy use and lowering CO2 emission if they are levied solely on all the fossil-fuel-related emission and fuel use in the systems. If consumer electricity and heat taxes are used, the taxes have an impact on the total cost, regardless of the fuel used, thereby benefiting fuel-based local heating systems. The heat pump systems were the least affected by taxes, due to their high energy efficiency. The electric boiler systems were the least cost efficient systems, also when the external cost and taxes were included.
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45. |
- Stenlund Nilsson Ivner, Jenny, 1976-
(author)
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Plan and Reality : Municipal Energy Plans and Development of Local Energy Systems
- 2006
-
Licentiate thesis (other academic/artistic)abstract
- Enligt lagen om kommunal energiplanering ska varje svensk kommun ha en energiplan för tillförsel för tillförsel och användning av energi. Huruvida energiplanering är ett bra sätt att styra det kommunala energisystemet är dock omdebatterat. Denna avhandling studerar innehåll i, och implementering av, ett antal svenska kommunala energiplaner. Energiplanernas effektivitet studeras på två nivåer: uppfyllelse av mål och visioner i planerna, samt hur detta bidrar till att uppfylla de nationella energipolitiska målen.Forskningen baseras på tre studier: en studie av innehållet i tolv energiplaner från Östergötland, en studie av mål och visioner i sju energiplaner och hur energisystem utvecklats efter energiplanerna antagits, samt en fallstudie av Kungälvs kommun där mål och måluppfyllelse studerats mer utförligt. Innehåll och målformuleringar i energiplanerna har analyserats med avseende på miljö, effektiv energianvändning och systemnivå. Mål och måluppfyllelse har även analyserats med avseende på aktörer.Resultaten visar på att de studerade energiplanerna har smal systemsyn och att de miljöanalyser som finns i planerna är undermåliga. Energiplaneringen har varit effektiv till viss del. Bäst måluppfyllelse har kommunerna när det gäller mål på en relativt låg systemnivå och när det är kommunen själv som äger frågan, exempelvis fjärrvärmeutbyggnad och energieffektivisering av kommunens lokaler. När det gäller utvecklingens bidrag till de nationella energipolitiska målen är resultaten varierande: användning av biobränslen har ökat avsevärt, medan självförsörjningsgraden på el bara ökat något. Bäst är utvecklingen när det gäller minskade koldioxidutsläpp.Baserat på bristerna som upptäckts i de studerade energiplanerna och dess implementering förs en diskussion kring möjligheter att öka energiplaneringens effektivitet och vidga systemsynen. Förbättringar som diskuteras är att stärka kopplingen till fysisk planering, och att inkludera medborgarmedverkan och miljöbedömningar. Om kopplingen till energifrågor stärks i översiktlig planering och om även privata aktörer kommer till tals under planeringsprocessen, skulle detta kunna underlätta implementering av energiplanerna. Miljöbedömningar i sin tur kan bidra med en vidare systemsyn om mer relevanta mål i planerna. Slutligen föreslås att ramverket för miljöbedömning av planer och program (2001/42/EC) kan användas vid energiplanering eftersom det framhåller vikten av breda analyser, samråd med privata aktörer och miljöbedömningar.
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46. |
- Ekener, Elisabeth, 1963-, et al.
(author)
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Developing Life Cycle Sustainability Assessment methodology by applying values-based sustainability weighting - Tested on biomass based and fossil transportation fuels
- 2018
-
In: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526 .- 1879-1786. ; 181, s. 337-351
-
Journal article (peer-reviewed)abstract
- The production and use of transportation fuels can lead to sustainability impacts. Assessing them simultaneously in a holistic way is a challenge. This paper examines methodology for assessing the sustainability performance of products in a more integrated way, including a broad range of social impacts. Life Cycle Sustainability Assessment (LCSA) methodology is applied for this assessment. LSCA often constitutes of the integration of results from social LCA (S-LCA), environmental life cycle assessment (E-LCA) and life cycle costing (LCC). In this study, an S-LCA from an earlier project is extended with a positive social aspect, as well as refined and detailed. E-LCA and LCC results are built from LCA database and literature. Multi Criteria Decision Analysis (MCDA) methodology is applied to integrate the results from the three different assessments into an LCSA. The weighting of key sustainability dimensions in the MCDA is performed in different ways, where the sustainability dimensions are prioritized differently priority based on the assumed values of different stakeholder profiles (Egalitarian, Hierarchist, and Individualist). The developed methodology is tested on selected biomass based and fossil transportation fuels - ethanol produced from Brazilian sugarcane and US corn/maize, and petrol produced from Russian and Nigerian crude oils, where it delineates differences in sustainability performance between products assessed. The outcome in terms of relative ranking of the transportation fuel chains based on sustain ability performance differs when applying different decision-maker profiles. This result highlights and supports views that there is no one single answer regarding which of the alternatives that is most sustainable. Rather, it depends strongly upon the worldview and values held by the decision maker. A key conclusion is that sustainability assessments should pay more attention to potential differences in underlying values held by key stakeholders in relevant societal contexts. The LCSA methodology still faces challenges regarding results integration but MCDA in combination with stakeholder profiles appears to be a useful approach to build on further.
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47. |
- de Klijn-Chevalerias, M., et al.
(author)
-
The Dutch approach for assessing and reducing environmental impacts of building materials
- 2017
-
In: Building and Environment. - : Elsevier BV. - 0360-1323. ; 111, s. 147-159
-
Journal article (peer-reviewed)abstract
- Buildings are one of the largest consumers of energy and materials, and hence they are also one of the largest contributors to negative environmental impacts. Traditionally, energy consumed by buildings during their operation phase was the most significant in their lifecycles and far exceeded the embodied energy. However, in contemporary low-energy buildings, the embodied energy is proportionally higher because of the prevalent use of energy-intensive materials. To determine the embodied energy and environmental impacts of building materials, the Dutch have developed an assessment method, which has also been adapted by BREEAM-NL. This paper offers an overview of the Dutch approach for assessing the environmental impacts of building materials and demonstrates its practical application. The use of the Dutch Assessment Method to identify, and quantify materials-related design improvements has been demonstrated through an exemplifying case study. It has been identified that the environmental impact of a building is largely influenced by the material choices made at the early design stage of the project.
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48. |
- 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.
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49. |
- Duwig, Christophe
(creator_code:cre_t)
-
Exhibition : Towards the energy of the future – the invisible revolution behind the electrical socket
- 2023
-
Artistic workabstract
- Energy Crisis! Electricity Price drama! The threat of global energy poverty! Media are generous with spectacular titles. Yes, energy is important, and yes, nearly all societal challenges are connected to how we convert, distribute and use energy. Therefore, the KTH Energy Platform and KTH Library presented an exhibition with the theme Towards the energy of the future – the invisible revolution behind the electrical socket.The exhibition displayed showcase illustrations from the book made by Lotta Waesterberg Tomasson, as well as books related to energy and electricity from the KTH Library's collections. In parallell with the exhibition, a series of live popular science lunch seminars with presentations of selected chapters of the book took place. As part of the exhibition, students from KTH's Electrical Engineering program also showcased exciting projects that connect to the anthology’s contents, made with materials and equipment from the student-driven ELAB and “Studentverkstan”. Visitors were also invited to share their reflections and ideas on energy.
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50. |
- Vujanović, M., et al.
(author)
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Special issue of applied energy dedicated to SDEWES conferences 2018 : Sustainable energy technologies and environmental impacts of energy systems
- 2019
-
In: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 256
-
Journal article (peer-reviewed)abstract
- This special issue of Applied Energy contains scientific articles presented at the 1st Latin American edition of the SDEWES conference conducted in 2018 in Rio de Janeiro, the 3rd South East Europe edition of SDEWES conference conducted in 2018 in Novi Sad, and the 13th SDEWES conference conducted in 2018 in Palermo. The SDEWES conferences are international scientific conferences that gather scientists and professionals from the field of sustainable development. These conferences have brought together 770 scientists, researchers, and experts in the field of sustainable development of energy and environment. This editorial is based upon 20 papers selected from among 700 contributions presented at the SDEWES conferences in 2018. The topics covered in this special issue include the advances in research and development in the energy sytems and technologies and its environmental impact within the framework of sustainable development.
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