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Optimized tower wall material, a numerical investigation on timber laminates
No full textTraditionally, wind turbine towers have been constructed using steel and concrete. However, growing environmental concerns, particularly the need to reduce carbon
emissions, have caused the search for alternative solutions across various sectors, including wind energy. One such solution is the use of laminated veneer lumber
(LVL) as a sustainable material for wind turbine towers. A notable example is the Wind of Change tower, developed by Modvion, which stands 105 meters tall and is
built from spruce LVL panels assembled with adhesives. This innovative approach reduces the environmental impact associated with traditional materials like steel and
concrete, while still ensuring that the tower meets structural performance requirements. However, the need to optimize the design to reduce material usage while
maintaining performance still arises.
The aim of this thesis is to investigate whether an optimized tower design can achieve the same structural performance as existing solutions while minimizing material use.
This is approached by designing two tower concepts and a benchmark model for a 166 meter tall wind turbine tower. Using Classic Laminate Theory (CLT), the study
explores the effect of LVL panel orientations in different sections of the tower to identify an optimal orientation, referred to as the sweet spot angle, that maximizes
safety factors under three defined load cases. The towers are evaluated against two failure criteria, Maximum Stress and Tsai-Hill, based on prior research correlating
these criteria with the behavior of LVL wood. The investigation focuses solely on numerical simulations, with no experimental validation included in the scope.
Results show that by optimizing the panel orientations, the total tower volume can be reduced by 15.4% while still meeting structural performance requirements
Increased Methane Uptake Under Long-Term Warming in Well-Drained Sub-Arctic Soil A Field Study of Gas Fluxes at Two Icelandic Sites Using Open-top Chambers and Methanotrophy Inhibition
No full textMethane (CH4) is the green house gas with the second largest contribution to global
warming. Well-drained soils make up 87% of the Arctic and have been observed to
be a CH4 sink. There exist several CH4 sources and sinks in the Arctic. One
of the CH4 sinks in the Arctic is CH4 oxidation by soil microorganism. Soil CH4
fluxes are depending on two microorganisms; methanotrophs which oxidize CH4 and
methanogens which produces CH4. However, there exists knowledge gaps about the
size of Arctic CH4 soil uptake, the drivers of the activity level of CH4 consuming
and producing microbes along with how the CH4 fluxes will change with global
warming. This study measured CH4 fluxes at two sub-Arctic Icelandic sites with
well-drained soil under ambient and passively heated conditions. The passive heating
was obtained through open-top chambers (OTC’s). CH4 fluxes were measured
at one moss-dominated site (Moss site), and one colder, more species rich heath site
(Heath site).
The results showed a 31,7% increase in CH4 uptake at the Moss site (p<0,05),
where the average uptake shifted from 0,790 ± 0,422 in Control plots to 1,04 ±
0,472 mg[CH4]m−2d−1 within the OTC plots. The size of these fluxes is in line with
previous studies of CH4 sinks in the Arctic during the growing season. Soil moisture
and soil temperature were measured, but neither factor could be determined as a
driver behind the increased CH4 uptake.
At the Heath site, no change in CH4 uptake was observed when comparing the OTC
and Control plots (p=0,84). Further more, the Heath site had a lower CH4 uptake
than the Moss site with an average uptake of around 0,037 ± 0,03 mg[CH4]m−2d−1,
about a tenth of what previous studies observed in well-drained Arctic soils during
the growing season. The small CH4 sink as well as no significant CH4 flux change
between the treatments is believed to be due to a late snow melt, leading to higher
soil moisture, lower soil temperature and a lower microbial activity.
Inhibitions of methanotrophic activity were conducted at the Heath site with acetylene
gas to separate the soil’s cooccuring production and consumption of CH4. A
slight CH4 production was observed within the soil for some of the inhibitions, indicating
that well-drained Arctic soils have active methanogens. However, too few
inhibition experiments could be completed for statistical analysis
A New Current Collector System for Lithium-ion Batteries
No full textThe study of rechargeable batteries has become increasingly important due to the
growing demand for efficient energy storage in electronic devices, electric vehicles,
and renewable energy systems. Within these batteries, current collectors act as
conductive bridges between the external circuit and the active electrode materials,
directly influencing the battery’s performance, weight, and cost.
Traditional anode current collectors are typically made of thin copper foil due
to its excellent electrical conductivity and mechanical properties. However, aluminium—
commonly used as a cathode current collector—can be coated with a
thin copper layer to create a composite material that offers comparable electrical
conductivity while reducing both weight and material costs.
In this thesis, such a composite foil, produced by coating a thin copper layer on
aluminium foil, was investigated for its application in batteries as anode current
collector and compared to commercial copper foil. The mechanical analysis revealed
strong adhesion between the copper coating and the aluminium substrate, along with
significantly improved adhesion of the electrode material to the collector compared
to that of pure copper foil.
Battery cycling performance was also evaluated. While the composite demonstrated
acceptable short-term cycling behaviour, its performance was ultimately limited by
defects in the copper layer. These defects led to undesirable side reactions between
the exposed aluminium and lithium within the cell.
With further optimization to eliminate these defects, the copper-coated aluminium
composite has the potential to be a cost-effective and lightweight alternative to
traditional copper current collectors—offering increased energy density without
compromising battery capacit
Chalmershindret 2025
No full textChalmershindret är ett årligt projekt i samarbete mellan Chalmers tekniska högskola och Göteborg Horse Show, där studenter utvecklar mätteknik för att analysera ekipagets prestation i hästhoppning. Årets projekt syftade till att mäta tiden över och mellan hinder med hjälp av geofoner som mäter markvibrationer. Utifrån vibrationsdata tränades en AI-modell för att identifiera avstamp och landning vid ett hinder.
Projektgruppen delades in i en teknikgrupp samt en PR- och designgrupp. Teknikgruppen utvecklade mätutrustningen, medan PR- och designgruppen fokuserade på publikupplevelse, marknadsföring och hinderdesign. Projektet avslutades med mätningar och publikaktiviteter på Göteborg Horse Show 2025.
Resultatet av mätningarna visade på vissa brister i AI-modellens tidsuppskattningar, och det kunde konstateras att mer träningsdata hade behövts för pålitligare resultat. Därför kompletterades mätningarna under Göteborg Horse Show med manuell tidtagning. Däremot visar vibrationsteknik potential för att i framtiden kunna bli ett användbart och effektivt analysverktyg för att mäta mellantider och tid i luften
AI - Driven Home Energy Management System for Profit and Grid Stability - Deep Reinforcement Learning and Predictive Models for Minimizing Peak Demand While Balancing Battery Degradation in a Dynamic Environment
No full textAbstract
This thesis presents the development and implementation of an AI-driven home energy management system designed to optimize residential battery storage in response to Sweden’s new power-based electricity tariffs, which introduce capacity fees based on avarage monthly power peaks starting January 2027. The system integrates three components: (1) multi-modal forecasting models for electricity prices, solar production, and household demand. (2) a Recurrent Proximal Policy Optimization (RPPO) reinforcement learning agent for real-time battery control and (3) automated orchestration via Prefect with Home Assistant integration. The forecasting stack (XGBoost and temporal convolutional networks (TCN)) achieves competitive
accuracy, and the RL agent, trained on a custom reward balancing cost, solar utilization, and safety, learns price arbitrage and solar aware charging strategies. Field deployment on a 22 kWh battery with a 20 kW dual-orientation PV array demonstrates integration with real hardware and shows preliminary economic benefits under simulated seasonal conditions. The agent maintains 100% safety compliance (zero charge/discharge violations during final deployment) while achieving high grid independence. Although additional computational time for full training convergence and hyperparameter tuning remains as future work, these preliminary results underscore the strong potential of AI-driven residential energy management for cost savings and grid support
Balancing heritage and innovation; adaptive reuse as a process of architectural continuity
No full textPreserving cultural and architectural heritage requires careful observation and
thoughtful strategies to ensure its continuity and relevance for future use. A
careful negotiation between heritage and innovation becomes necessary to translate
tangible and intangible elements from the past into the future.
This thesis explored the possibilities of adaptive reuse as a strategy of transforming
historic industrial buildings into future oriented projects. The Lyckholms Brewery
in Gothenburg was used as a case study to investigate how contemporary interventions
influence the balance between old and new.
The research incorporated different theoretical frameworks, such as Genius Loci,
Aemulatio, industrial heritage, and other adaptive reuse approaches like architectural,
programmatic, or interior approaches to apply as design methods. Through
a comprehensive inventory, analysis, and an iterative design loop, the thesis
developed into a proposal for a mixed-use cultural house with residential functions.
Special attention was given to the significance of feasibility as an essential design
factor in both academic and real-world contexts.
The resulting design project showcased how transformation could act as a form
of preservation, working towards a spatial and cultural revitalisation that not
only preserved the past but also activated it for the present and future. The
design project is represented in the form of drawings, images and models to
showcase the impact of the transformation.
The thesis concluded that adaptive reuse is not a compromise between old and
new, but a strategy for architectural continuity, preserving identity while integrating
innovative design solution
Simulating Drone-Enhanced Emergency Medical Services
No full textThis thesis explores how simulation can support the development and adoption of Drone-Enhanced Emergency Medical Services (DEMS), with a specific focus on improving early situational awareness (SA) among Helicopter Emergency Medical Services (HEMS) coordinators. In collaboration with Everdrone AB, a simulator was designed to replicate the LiveView system used in real emergencies, enabling users to engage in scenario-based training without real-world risks. The simulator includes common emergency scenarios, such as a traffic accident, a building fire, and an automated external defibrillator (AED) delivery, and was developed using principles of interaction design, telepresence, and simulation-based learning. An evaluation through interviews with stakeholders in the field highlights the simulator’s value in enhancing decision-making, SA, and preparedness. The results suggest that simulated DEMS can facilitate training, inform future system development, and contribute to safer and more effective emergency response strategies
Samband i boendemiljön mellan samhällsbuller och socioekonomiska faktorer; hur ser det ut i Göteborg
No full textStudien är ett kandidatarbete gjort vid avdelningen för Teknisk Akustik, Chalmers Tekniska
Högskola, Göteborg. Syftet med detta arbete är att undersöka om det finns samband mellan
socioekonomiska faktorer och bullerexponering i olika delar av Göteborg. Tre av Göteborgs
stadsområden undersöks, där två primärområden med olika socioekonomiska förhållanden
från varje stadsområde har valts ut.
Buller utgör idag ett betydande samhällsproblem, då det är den miljöstörning som påverkar
flest människor i Sverige (Naturvårdsverket, 2025). Buller kan påverka hälsan både på kort
och lång sikt, och konsekvenserna kan i vissa fall vara allvarliga. Trots denna kunskap
uppskattas det att cirka 2 miljoner människor exponeras för bullernivåer som överskrider
riktvärdena vid deras bostäder i Sverige.
Göteborgs Stad publicerade 2023 en jämlikhetsrapport som visade att staden lider av
ojämlikhet och att det finns hälsoskillnader inom befolkningen kopplat till socioekonomiska
faktorer (Göteborgs stad, 2023). Om Göteborg delas upp efter inkomst får staden ett
ojämlikhetsindex på 53,0 % på en skala från 0-100 %.
Arbetet har genomförts med hjälp av ljudmätningar och intervjuer med boende i
primärområdena. Mätningar av bullernivåer har gjorts på flera olika platser i varje
primärområde för att kunna avgöra hur stor bullerexponering boende i de olika områdena
utsätts för.
Resultatet av det ovan beskrivna arbetet visar att det finns ett samband mellan
socioekonomisk utsatthet och bullernivåer. Detta samband har påvisats både genom
ljudnivåmätningar och beräkningar av årsdygnsmedelvärden. Det ska dock betonas att
relationen mellan buller och socioekonomiska förhållanden är komplex och påverkas av en
rad samverkande faktorer. Trafikmängd, fysisk miljö, stadsplanering och lokala geografiska
förutsättningar spelar en avgörande roll, vilket även intervjustudien indiker
Establishing Strategic Technology Partnerships in Robotics Navigating R&D Collaboration and Geopolitical Risk in High-Tech Innovation
No full textAs high-tech firms increasingly engage in external collaboration to accelerate R&D, they must
navigate complex trade-offs between openness, control, and geopolitical risk. This thesis
investigates how a high-tech firm adapts its R&D strategy and partner selection processes
under geopolitical complexity, with two guiding research questions:
RQ1: How does the focal high-tech firm adapt its R&D strategy and external collaboration
model, including partner selection, under geopolitical risk?
RQ2: What challenges and strategic trade-offs does the firm face when selecting external
collaborators under geopolitical risk?
The study is based on a qualitative single-case study of a strategic collaboration project
involving suppliers of advanced vision and processing technologies, with a focus on
partnerships in China. The empirical foundation comprises nine semi-structured interviews with
stakeholders across sourcing, R&D, and strategy functions, supported by internal
documentation and informal interactions. Using an abductive approach and thematic analysis,
the study captures how the firm’s collaboration model evolved from closed innovation toward
selective openness.
The findings reveal that partner selection is guided by a dynamic logic integrating technological
competence, organizational alignment, and geopolitical foresight. However, the shift to external
collaboration creates coordination complexity, capability gaps, and motivational challenges
particularly in triadic collaboration settings. Geopolitical risk is not treated as a fixed constraint
but as a structural input shaping design, governance, and substitution strategies.
The thesis contributes to open innovation literature by highlighting how geopolitical
considerations are operationalized in partner selection and collaboration models. It proposes
three managerial levers for increasing resilience: a cross-functional partner selection
framework, modular product architectures with substitution options, and improve internal
collaboration readiness. These insights inform how high-tech firms can structure externally
oriented R&D strategies that remain robust in geopolitical risk
Strategic municipal property management Identifying challenges and solutions within municipal property management
No full textKommunala fastigheter utgör en av samhällets största resurser och spelar en avgörande roll
för att tillhandahålla samhällsviktiga funktioner som utbildning, vård och omsorg. Samtidigt
står många kommuner inför stora utmaningar relaterade till underhåll och långsiktig
förvaltning av ett åldrande fastighetsbestånd. En stor andel av fastigheterna byggdes under
mitten av 1900-talet utan tydliga underhållsplaner, vilket har lett till omfattande
underhållsskulder. Detta har i sin tur resulterat i höga kostnader, ineffektiva lösningar och
svårigheter att möta dagens hållbarhetskrav. För att hantera dessa utmaningar kan det behövas
ett förändrat arbetssätt inom kommunal fastighetsförvaltning.
Detta kandidatarbete syftar därför på att undersöka utmaningar och möjligheter inom
kommunal fastighetsförvaltning, med särskilt intresse av strategisk kommunal
fastighetsförvaltning. Genom att analysera och jämföra utmaningar och lösningar inom
kommunal fastighetsförvaltning, identifierar rapporten åtgärder som kan bidra till mer
hållbara och effektiva arbetssätt.
Arbetet bygger på en kombination av metoder. En litteraturstudie genomfördes för att skapa
en teoretisk förståelse av ämnet, detta följdes av en enkätstudie riktad till kommunanställda
inom fastighetsförvaltning. Intervjuer med fem tjänstemän som arbetar inom olika kommuner
samt en ämnesexpert genomfördes därefter. Resultaten visar att de största utmaningarna rör
bristande långsiktig planering, otillräckliga resurser, politisk påverkan, samt otydliga
organisatoriska strukturer. Samtidigt framkommer att flera kommuner har börjat ett
omställningsarbete med strategier för lokalförsörjning, digitala verktyg samt ökad samverkan.
Arbetet visar att det inte finns en universallösning, men att strategisk fastighetsförvaltning
kan fungera som ett ramverk för att möta de krav som kommunerna står inför. På kort sikt
krävs organisatoriska och tekniska effektiviseringar, medan det på lång sikt är nödvändigt att
kombinera dessa med strategisk planering för att säkra en hållbar förvaltning av
kommunernas fastighetsbestånd.
Notera: Rapporten är skriven på engelsk