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Påskynda användningen av permanenta koldioxidavskiljnings metoder
No full textCarbon capture and storage (CCS) is widely recognized as a complementary measure to ongoing emissions reduction efforts and global climate targets. However, the large-scale deployment of durable carbon dioxide removal (CDR) technologies, such as Bioenergy with Carbon Capture and Storage (BECCS), is still in early stages. Thus, this study explores potential commercialization mechanisms that could drive the broader implementation of BECCS. Proposed options include integrating CDR into the EU Emissions Trading System (EU ETS), creating a European Carbon Central Bank, combining the Voluntary Carbon Market with subsidies or tax credits, and gradually implementing quota obligations.
The study is constructed from the perspective of a company considering investment in BECCS. Thus, the research adopts a qualitative approach to identify key challenges and factors to consider for such investments. To gain a comprehensive understanding of the current CDR landscape, the study integrates findings from literature with insights gathered through semi-structured interviews. The overall focus is on the European context, with particular emphasis placed on Finland.
The thesis concludes with recommendation for commercialization mechanisms and additional actions necessary to accelerate BECCS market development. These include integrating durable CDR into the EU ETS and establishing a European Carbon Central Bank. Further considerations are given to factors such as regulatory gaps and accounting of climate claims. Finally, the thesis highlights persisting uncertainties and unresolved questions, presenting them as recommendations for future research.Avskiljning och lagring av koldioxid (CCS) är allmänt accepterat som en komplementär åtgärd för pågående utsläppsminskningar och globala klimatmål. Dock är den storskaliga implementeringen av permanenta koldioxidavskiljnings (CDR) metoder, till exempel bioenergi med CCS (BECCS), fortfarande i ett tidigt skede. På grund av detta, undersöker denna diplomarbete potentiella kommersialisering mekanismer för att driva en bredare implementering av BECCS. Ofta förekommande alternative består av att integrera CDR i EU:s utsläppshandelssystem (EU ETS), grunda en Europeisk centralbank för kol, kombinera den frivilliga koldioxidmarknaden med subventioner eller skattelättnader, samt gradvis implementera kvotplikter.
Diplomarbetet är strukturerat utifrån ett investeringsperspektiv på BECCS. Därför används en kvalitativ metod för att identifiera utmaningar och viktiga faktorer att beakta vid ett investeringsbeslut. För att erhålla en omfattande bild av den aktuella situationen, integrerar arbetet resultat från litteraturen med insikter från semistrukturerade intervjuer. Fokuset är på den europeiska kontexten, med särskild uppmärksamhet på Finland.
Diplomarbetet avslutas med rekommendationer för kommersialisering mekanismer samt ytterligare åtgärder för att accelerera utvecklingen av BECCS-marknaden. Till dessa tillhör att integrera permanent koldioxidavskiljning (CDR) i EU:s utsläppshandelssytem och att grunda en Europeisk centralbank för kol. Även oklarheter kring EU-förordningar och direktiv, samt bokförning av klimatpåståenden beaktas. Slutligen lyfts fram kvarstående frågor och rekommendationer för framtida forskning
Techno-economic model for evaluating the economic feasibility of green hydrogen production within an electrical storage and grid-connected system
No full textThe transition to a low-carbon energy system has increased interest in green hydrogen as a sustainable energy carrier. This thesis presents a comprehensive techno-economic model designed to assess the economic feasibility of green hydrogen production within an RES integrated system that includes electrical storage and grid connectivity.
The model takes into account real-time electricity market dynamics, variability in renewable energy sources (RES), and interactions among system components such as the electrolyser, battery, RES assets, and the grid. Using a mixed-integer linear programming (MILP) approach, optimal dispatch schedules are derived to minimise costs and maximise revenues from hydrogen production and participation in the energy market for a given system configuration.
A large number of simulations are conducted with varying system configurations to create a landscape of hydrogen generation prices. The case studies, which apply real-world data, indicate that under current market conditions, green hydrogen does not achieve parity with conventional grey hydrogen. Additionally, the inclusion of electrical storage appears to negatively affect profitability.
Key parameters, such as electricity prices, capital expenditures (CAPEX), and local factors, critically influence the viability of green hydrogen projects. Furthermore, maintaining a high capacity factor for the electrolyser depends significantly on grid connection. The findings conclude that, to make green hydrogen generation profitable with on-site assets, it is necessary to oversize RES assets and ensure that grid charges and power prices are favourable. While high variability in power prices may benefit arbitrage opportunities, it currently does not sufficiently offset the capital costs associated with electrical storage
Organic radicals in batteries
No full textTämä kandidaatintutkielma tarkastelee orgaanisia radikaaleja ja niiden soveltuvuutta akkuteknologiaan. Orgaaniset radikaalit, radikaalimolekyylit ja radikaalipolymeerit tarjoavat lupaavan vaihtoehdon ladattaville akuille niiden nopeiden redoxreaktioiden, kohtuullisen elektrodikapasiteetin ja pitkän lataus-purkausjaksojen kestävyyden ansiosta.
Orgaanisten radikaalien hyödyntäminen akkuteknologiassa voi myös mahdollistaa kevyempien ja edullisempien akkumateriaalien kehittämisen verrattuna perinteisiin akkumateriaaleihin, kuten litiumiin ja kobolttiin. Lisäksi orgaanisten materiaalien kierrätettävyys ja ympäristöystävällisyys tekevät niistä houkuttelevan vaihtoehdon
kestävämmän energian varastointiteknologian kehittämiseksi. Tutkimuksessa tarkastellaan orgaanisten radikaalien kemiallisia ja sähkökemiallisia ominaisuuksia, niiden vuorovaikutuksia elektrolyyttien kanssa sekä niiden käytettävyyttä eri akkuteknologioissa.
Orgaaniset radikaalit voivat toimia joko elektrodiaktiivisina materiaaleina tai elektrodireaktioita välittävinä aineina. Esimerkiksi radikaalipolymeerit, kuten TEMPOkorvattu polymetakrylaatti, ovat osoittaneet erinomaisia lataus-purkauskapasiteetteja ja pitkän eliniän. Lisäksi orgaaniset akkuteknologiat, jotka hyödyntävät täysin orgaanisia polymeerikatodeja ja -anodeja, tarjoavat ympäristöystävällisemmän vaihtoehdon perinteisille akuille ilman raskasmetalleja.
Tutkimuksessa tarkastellaan orgaanisten radikaalien kemiallisia ja sähkökemiallisia ominaisuuksia, niiden vuorovaikutuksia elektrolyyttien kanssa sekä soveltuvuutta eri akkuteknologioihin.This bachelor’s thesis examines organic radicals and their suitability for battery technology. Organic radicals, radical molecules, and radical polymers offer a promising alternative for rechargeable batteries due to their fast redox reactions, reasonable electrode capacity, and durability over long charge-discharge cycles.
Utilizing organic radicals in battery technology may also enable the development of lighter and more cost-effective battery materials compared to traditional materials such as lithium and cobalt. Furthermore, the recyclability and environmental friendliness of organic materials make them an attractive option for the development of more sustainable energy storage technologies. This study explores the chemical and electrochemical properties of organic radicals, their interactions with electrolytes, and their usability in various battery technologies.
Organic radicals can function either as electrode-active materials or as mediators of electrode reactions. For example, radical polymers such as TEMPO-substituted polymethacrylate have demonstrated excellent charge-discharge capacities and long lifespans. In addition, organic battery technologies that utilize fully organic polymer cathodes and anodes offer a more environmentally friendly alternative to conventional batteries without the use of heavy metals.
This study examines the chemical and electrochemical properties of organic radicals, their interactions with electrolytes, and their applicability to different battery technologies
Cyberpunk 2077 – Utilizing typography in creating an immersive gaming experience
No full textTämä opinnäyte käsittelee typografian hyödyntämistä immersiivisen pelikokemuksen luomisessa Cyberpunk 2077 videopelissä. Opinnäytteen tavoitteena on havainnoida Cyberpunk 2077 videopelissä tehtyjä typografisia valintoja sekä kartoittaa sitä, miten typografisia keinoja hyödyntämällä voidaan tukea immersiivistä pelikokemusta. Opinnäyte käsittelee typografiaa pelin sisäisen maailman näkökulmasta, joten rajauksen ulkopuolelle jää pelin käyttöliittymissä käytetty typografia. Typografian ja immersion keskinäisen suhteen analysointia lähestytään opinnäytteessä immersion tasojen sekä Cyberpunk 2077:ssa tehtyjen typografisten keinojen kautta. Tämän lisäksi opinnäytteeseen sisältyy produktio, jonka tarkoituksena on täydentää pohdintaa typografian ja immersion keskinäisestä suhteesta subjektiivisemmasta näkökulmasta. Produktio on toteutettu fyysisenä kokoelmana kuvia, joissa tuodaan laajemmin esiin Cyberpunk 2077:ssa esiintyvää typografiaa.
Opinnäytteen keskeisimmäksi tulokseksi osoittautui pelimaailman johdonmukaisen sekä huolitellun typografian rooli immersion syntymisen ja ylläpitämisen kannalta. Opinnäytteessä havaittiin, että typografian avulla saatiin luotua pelimaailmaan eloa sekä realistisuuden tunnetta. Tämä teki pelikokemuksesta visuaalisesti nautittavamman ja auttoi myös eläytymään pelin tunnelmaan. Toisaalta opinnäytteessä havaittiin myös, että mikäli pelimaailman typografia ei pysy visuaalisesti johdonmukaisena, saattaa uppoutuminen pelimaailmaan häiriintyä, jolloin myös immersiivinen pelikokemus katkeaa
4-O-Methylglucaric Acid Production from Xylan with Uronic Acid Oxidase and Comparison to Glucaric Acid from Glucose
No full textPublisher Copyright: © 2025 The Author(s). ChemBioChem published by Wiley-VCH GmbH.This study describes an enzymatic pathway to produce high purity 4-O-methylglucaric acid from xylan, an underutilized fraction of lignocellulosic biomass. Beechwood xylan was enzymatically hydrolysed using a commercial xylanase and an α-glucuronidase from Amphibacillus xylanus to form 4-O-methylglucuronic acid, which was then purified by anion exchange chromatography and subsequently oxidized to 4-O-methylglucaric acid using a recombinantly produced uronic acid oxidase from Citrus sinensis. Enzymatic oxidation with uronic acid oxidase afforded 95 % yield in 72 hours which is considerably higher than yields previously achieved using a glucooligosaccharide oxidase from Sarocladium strictum. 4-O-methylglucaric acid was isolated by precipitation and purified by recrystallization. Characterization by liquid chromatography mass spectrometry and nuclear magnetic resonance spectroscopy confirmed product identity and high purity (97.8 % w/w). 4-O-methylglucaric acid's performance as a detergent builder was compared to commercial glucaric acid. At 10 : 1 molar ratios of detergent builder to calcium, 4-O-methylglucaric acid provided similar calcium sequestration performance to glucaric acid (less than 5 % difference) at pH 7 and pH 10 in the presence of surfactants, including sodium dodecylbenzene sulfonate. Given their similar calcium sequestration performance, 4-O-methylglucaric acid could effectively substitute for glucaric acid in detergent formulations.Peer reviewe
Bounding the rotating wave approximation for coupled harmonic oscillators
No full textPublisher Copyright: © 2025 The Author(s). Published by IOP Publishing Ltd.In this work we study the validity of the rotating wave approximation of an ideal system composed of two harmonic oscillators evolving with a quadratic Hamiltonian and arbitrarily strong interaction. We prove its validity for arbitrary states by bounding the error introduced. We then restrict ourselves to the dynamics of Gaussian states and are able to fully quantify the deviation of arbitrary pure Gaussian states that evolve through different dynamics from a common quantum state. We show that this distance is fully determined by the first and second moments of the statistical distribution of the number of excitations created from the vacuum during an appropriate effective time-evolution. We use these results to completely control the dynamics for this class of states, therefore providing a toolbox to be used in quantum optics and quantum information. Applications and potential physical implementations are also discussed.Peer reviewe
Walking in My Shoes : An Autoethnography of Techno-Spiritual Practices
No full textTechnology has become deeply woven into the practices of faith communities who engage in shared prayer, online worship, or meditation. Despite a growing body of research on religious/spiritual practices, the Human-Computer Interaction (HCI) community has yet to fully investigate Techno-Spirituality, especially through a first-person approach. We explored prayer experiences to understand which elements evoke such experiences from a Christian perspective. We present results from an eight-month autoethnographic study of private prayer by the first author, also a community member, while incorporating both technological (e.g., a Muse 2 electroencephalogram headband) and non-technological (e.g., religious iconography) media. We reflect on emerging practices and limitations of integrating technology during Christian prayer. This paper provides empirical insights on spiritual practices with technologies, and contributes to discourses on Techno-Spirituality in HCI.Peer reviewe
Reduced environmental impact of short sea shipping through optimal propulsion power allocation
No full textPublisher Copyright: © 2025 The AuthorsTo reduce the environmental impact of short sea shipping, this study introduces a two-stage propulsion power allocation method aimed at enhancing ship operational efficiency in various weather environments. The first stage utilizes a metocean score-based pruned explicit linear time (MS-PELT) algorithm to segment the trajectory into several legs based on metocean conditions, thereby minimizing frequent engine setting adjustments and simplifying the optimization process. In the second stage, a parallel coupling Dynamic Programming (PCDP) method is introduced to optimize power allocation in each leg using machine learning-based ship performance models. The proposed approach is evaluated using three years of full-scale operational data from a case study chemical tanker. Results show that the MS-PELT method outperforms the state-of-the-art multivariate clustering algorithm by providing practical and efficient segmentation. The optimized power allocation strategy demonstrates a promising average of 8 % emission and environmental impact reductions for case study short sea voyages with good computational efficiency. It is suitable for real-time applications, providing the maritime industry with tools to optimize ship engine settings, reducing emissions and environmental impact.Peer reviewe
Enhancing Safety for Autonomous VTOL Drone Deliveries Through Range, Flight Time, and Battery Predictions
No full textAccurate range and battery consumption estimation are critical to the safe and efficient flight of autonomous VTOL UAVs, particularly in Beyond Visual Line of Sight (BVLOS) operations. This thesis presents a data-driven approach to computing Estimated Battery at Landing (EBL) and Estimated Time of Arrival (ETA), meeting the need for accurate pre-flight planning and dynamic adjustment during drone deliveries. The Range Estimator suggestedwas integrated with RigiTech’s centralized platform (RigiCloud) and onboard systems so that ongoing adjustment to estimation could be done from real-time flight data. The model was subsequently trained on historical flight logs to identify patterns of consumption by payload and mission parameters. Realworld testing demonstrated that although there was variability in energy consumption among various flights, the system is extremely accurate at estimating both battery usage and flight time.
The findings show that the utilization of historical flight data is adequate for building a comprehensive consumption model, although additional refinements can enhance its ability to handle diverse environmental and hardware conditions. Future research will involve integrating real-time meteorological data, enhancing battery degradation modelling, and allowing more autonomous decision-making. This study adds to the enhancement of safety and reliability in UAV delivery, especially in critical applications such as medical logistics
The impact of Additive Manufacturing on supply chain resilience : a Delphi study
No full textPublisher Copyright: © 2025 The AuthorsThis study examines the impact of Additive Manufacturing (AM) on supply chain resilience (SCR) using Pettit et al.'s framework, which links SCR to supply chain (SC) vulnerabilities and capabilities. Given the lack of quantitative and empirical research on this topic, a Delphi study was conducted to determine whether AM has a positive or negative effect on these factors. The findings indicate that AM generally enhances SCR by improving key SC capabilities and vulnerabilities such as “Adaptability” and “Efficiency”. However, it also presents challenges as it negatively affects SC capabilities and vulnerabilities like “Resource limitations” and “Flexibility”. As such, AM adoption is not universally beneficial. Managers should hence assess their companies' SC capabilities and vulnerabilities, and invest in AM only if it strengthens their weakest areas. Furthermore, this study explores potential future scenarios for AM adoption in SCR. The findings identify two potential scenarios, with expected increases in AM use for SCR of up to 30 %. The study also outlines the required interventions and investments for the realization of these scenarios, offering practical insights for companies and policymakers. These insights guide stakeholders in identifying necessary interventions and understanding how these investments will impact the use of AM for SCR.Peer reviewe