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Design optimisation of integrated port energy systems linking electricity, heat and hydrogen
Full text linkEnergy system integration and sector coupling can be important enablers for decarbonisation in ports by improving energy system flexibility and possibilities for further value creation. This study presents a techno-economic optimisation of two Norwegian ports with varying degrees of sector coupling: a large cargo port focusing on increased electrification; and an offshore supply base also focusing on renewable fuel production and utilisation of surplus heat. PV panels and battery storage are considered for both ports. The profitability of PV panels is highly affected by future spot prices for electricity; the biggest investments are 3.2 MWp in the cargo port and 6.6 MWp for the supply base. The optimal battery size is affected by demand variability and capacity tariffs. The installed capacities are up to 1.8 MWh for the cargo port and 4.8 MWh for the supply base. If flexible fuel production is part of the port operation strategy, investment in batteries becomes less attractive. Further, if surplus heat is available from large-scale fuel production, investing in infrastructure for exporting heat to a neDesign optimisation of integrated port energy systems linking electricity, heat and hydrogenpublishedVersio
Urban ventilasjon. Ventilasjon for godt inneklima i urbane boliger
Full text linkDenne rapporten oppsummerer hovedresultater fra prosjektet Healthy Energy-efficient Urban Home Ventilation, også kalt Urban Ventilation. Prosjektets hovedmål har vært å etablere kunnskap om og gi anbefalinger til robuste ventilasjonsløsninger for boliger i et urbant miljø. Et politisk ønske om fortetting av byer gjorde det spesielt interessant å undersøke «urbane boliger», det vil i praksis si arealeffektive ett- til treroms blokkleiligheter. Byggemåter, regelverk og husholdningsstruktur har gjennomgått betydelige endringer de siste tiårene, men regelverket for boligventilasjon er lite endret.
Prosjektet har særlig undersøkt ventilasjon av kjøkken og bad. Disse rommene inneholder sterke og varierende kilder til forurensning og fukt, og eksisterende løsninger med forsert avtrekk er kompliserende for ventilasjonsløsningen. Krav til luftmengde bidrar også til høyt luftskifte i små leiligheter. Resultatene gir dokumentasjon for hva som er akseptable ventilasjonsløsninger og hvilke luftmengder som er best med hensyn til inneklima, energi- og effektbehov samt fuktpåkjenningen på konstruksjonen.
Åpen kjøkken-stue-løsning er dominerende i urbane leiligheter. Koketopp plasseres mot vegg, og selv små husholdninger lager varm mat én til to ganger per dag. Støy er en viktig årsak til begrenset bruk av kjøkkenventilator.
Effektiv kjøkkenventilasjon er avgjørende for å redusere eksponeringen for partikler og gasser fra matlaging. Våre forsøk viser at forsert luftmengde for kjøkkenventilatorer bør økes til minst 180 m³/h for å gi akseptabel osoppfangingsevne. Med avtrekk til det fri viser downdraft-løsninger gode resultater på lik linje med standard kjøkkenhetter. Avtrekk til det fri er per i dag den foretrukne løsningen. Kullfilter fjerner godt VOC-er forbundet med lukt, mens øvrige VOC-er fjernes i mindre eller liten grad. Høye luftmengder er ugunstig for fjerning av VOC. De undersøkte filtrene fjerner også i liten grad de minste partiklene. Helseeffekten av eksponering for slike partikler er dårlig kjent, og en varsom holdning anbefales.
Prosjektet har undersøkt behovet for ventilasjon for å håndtere fuktighet fra matlaging, dusjing og tørking av klær. Fuktbelastningen vil variere sterkt ut fra antall beboere og brukervaner. Bad med gulvvarme og én til to brukere vil med dagens preaksepterte ytelser ha lite behov for forsering. Med normal fuktbelastning fra dusjing og tørking av tøy, vil et avtrekk på 75 m3/h fra bad være tilstrekkelig, enten som fast luftmengde eller ved behovsstyrt forsering. Tung og gjentakende fuktbelastning fra fire personer krever noe høyere luftmengder enn friskluftkravet for fire sengeplasser. Luftmengdene som trengs for å håndtere høy fuktbelastning, vil for de fleste bruksscenarier gi lange perioder med svært tørr luft om vinteren.
Forsering på kjøkken og bad samt gjenvinning av kjøkkenavtrekk gir små konsekvenser for energiforbruket, siden driftstiden er kort. Uforholdsmessig høye luftmengder bør likevel unngås. Riktig total luftmengde som er tilpasset belastningen, gir både energibesparelse og bedre inneklima. Energikonsekvensen er størst for små leiligheter ved økt grunnventilasjon. Desentraliserte ventilasjonssystemer med resirkulerende kjøkkenhetter er de mest energieffektive løsningene, og riktig utformede systemer kan balansere energieffektivitet med innendørs luftkvalitet. Resirkulerende løsninger kan først anbefales når produktutvikling og dokumentasjon viser tilstrekkelig redusert eksponering av små partikler og VOC-er. I tillegg bør langtidseffekten av filtrene undersøkes nærmere. I urbane områder med begrenset mulighet for vinduslufting, bør det gjøres en særskilt vurdering av luftmengdebehov for personer og overtemperatur.
Dagens krav til luftmengder i boliger bør revideres i tråd med funnene fra prosjektet. Kjøkkenventilatorer bør testes med tanke på osoppfangingsevne, støynivå og energibruk for ulike luftmengder, og det bør settes krav til ytelse ved minimum luftmengde. Luftmengder generelt bør kunne reguleres og tilpasses leilighetenes størrelse og forventet belastning.publishedVersio
Effect of use of zero-carbon and low-carbon fuels on the performance of compact combined cycles for power generation
Full text linkOffshore electrical power is normally generated with several gas turbines running on natural gas produced on-site. These account for about 85% of the CO2 -emissions from the oil and gas sector in Norway. About 24% reduction of these emissions can be achieved by installing a steam bottoming cycle. Switching to zero-carbon fuels can be a future option to fully remove these emissions. Only a few offshore steam bottoming cycles are installed today, and gas turbines running on non-carbon fuels are technology under development. This study aims to quantify and analyze the effects on the performance of an offshore combined cycle after switching the gas turbine fuel from natural gas to alternatives with lower environmental impact. The fuels and fuel blends considered include hydrogen, ammonia, bio-methanol, and mixtures thereof — all of which have the potential to reduce overall CO2 intensity of power production. Hydrogen and ammonia, in particular, offer direct reductions in CO2 emissions. In our analysis we want to answer the following: - (1) will an installed steam bottoming cycle produce the same amount of power and operate under similar conditions when switching fuels? (2) For the different fuels, how much fuel would a combined cycle save with the same total power output? and, (3) What is the estimated total emission reduction potential for different fuel alternatives? The study is based on a common offshore configuration composed of four 40 MW gas turbines operating in simple cycle. In our analysis we replace one of them with a steam bottoming cycle and the results show that the net power output from the steam cycle across the fuels varied from 42.7 to 46.4 MW using equal steam cycle assumptions, with the ammonia-dominated mixtures showing the best performance. A once-through steam generator (OTSG) was designed for natural gas exhaust and applied in an improved cycle optimization aimed at maximizing steam bottoming cycle net power output while maintaining a fixed total power production. Results indicate significant fuel-saving potential ranging from 157 t/day for natural gas to 462 t/day for ammonia as fuel. These fuel-saving potentials were further used to estimate the potential for greenhouse gas emissions. The results showed that the reductions would be in the range of 85%–91% for the zero-carbon fuels. For bio-methanol, the emission reduction could vary from 4% to 70% depending on the production pathway.publishedVersio
Do we have to choose between the ecosystems and the energy transition? Environmental trade-offs with operation of Norwegian hydropower
Full text linkIn Norway, environmental constraints applying to hydropower may become stricter to safeguard local ecosystems. At the same time, Norwegian hydropower can facilitate the transition to more renewable energy within Northern Europe. This study quantifies the aggregated impact of environmental constraints on the Norwegian power system and its interactions with neighbouring countries up to 2050. Requirements for augmented protection of the local environment affect hydropower operation and, hence, the power system. For example, a loss of 3% in production combined with a 4% reduction in average hourly ramp for the Norwegian hydropower fleet results in our case study in up to a 14% increase in average Norwegian power prices and 4% increase in congestion on transmission lines towards neighbouring countries. The abundance of cheap renewable energy can mitigate price augmentation, but losses in flexibility can be difficult to recover completely within the existing hydropower infrastructure. While prioritizing hydropower plants with vulnerable surrounding ecosystems for adding new environmental targets helps limit their constraining effect on the power system, it also leads to an economic disparity between individual plants; stricter environmental constraints on parts of the hydropower fleet increase the revenues of the unaffected part (by up to 10% in our case study).Do we have to choose between the ecosystems and the energy transition? Environmental trade-offs with operation of Norwegian hydropowerpublishedVersio
Distribution Grid Operational Planning with Flexibility Resources
Full text linkThis report proposes a comprehensive operational planning framework and implementation strategy for distribution system operators (DSOs) transitioning toward "active" distribution grids. The report examines current planning practices, highlights the need for updates in long-term, mid-term, short-term, and real-time operations, and proposes a new operational framework to manage this complexity. Key stages for gradual implementation are outlined, each introducing progressively advanced tools and automation capabilities. To validate the framework, the report recommends phased testing in realistic environments, and some learned lessons are highlighted.Distribution Grid Operational Planning with Flexibility ResourcespublishedVersio
Field and laboratory investigations on condition assessment of ASR-affected structures
Full text linkThis paper aims at providing a critical analysis of the applicability of engineering tools for the condition assessment of ASR-affected structures, focusing on visual quantification of external and internal cracking and moisture condition measurements. The main objective of the presented investigations was to demonstrate how such engineering tools can provide important data regarding condition of the concrete and, in turn, help the selection of proper maintenance strategies. The paper analyses data on the extent of reaction/damage in concrete components incorporating different reactive aggregates and alkali content, and with varying exposure conditions (moisture access). A surface cracking mapping method was applied during the in-situ inspections. In the laboratory, the internal damage and moisture condition were assessed on extracted cores, primarily by use of the Damage Rating Index (DRI) and Degree of Capillary Saturation (DCS). The results highlight the challenges of investigating ASR in affected structures and the importance of using suitable tools, as the external and internal conditions of the concrete can vary significantly in the same structure or component, despite similar exposure conditions. The potential causes for such variability include the concrete composition, the aggregate reactivity, the reinforcement detailing and other forms of movement restraints and the loading conditions. The condition assessment tools used throughout this study usually allowed to better document/explain different scenarios observed during several field investigations. The influence of moisture access upon ASR damage generation was also clearly illustrated in several case studies. In general, external and internal signs of damage tend to correlate well with one another. However, internal condition can significantly vary over the depth of an investigated component and this feature should be considered when diagnosing ASR.publishedVersio
Pareto-Based Design Optimisation of Hybrid Energy Storage Systems for Full-Electric Vessels
Full text linkFull electric vessels can benefit from hybrid energy storage systems (HESS) that combine two storage technologies of different characteristics in terms of power and energy density. The optimal design of a HESS for a vessel is generally a rather complex multivariable optimization with several degrees of freedom and constraints. Indeed, the optimization should account for the operational characteristics of the storage units, including their progressive aging. Moreover, the sizing of the storage units is tightly linked to the strategy implemented in the energy management system (EMS) for allocating the power needed by the load to the storage units. This paper presents a two-stage Pareto-based design optimization procedure for HESS intended for a full-electric vessel. The methodology first identifies a Pareto front as the set of all the optimal configurations in terms of capacity of the two storage units that fulfil the operational constraints within a large discrete configuration space. These constraints account for capacity degradation and limitations in power and energy. The degrees of freedom in the EMS are included in the configuration space. A second stage identifies the optimal configuration on the Pareto front based on a defined cost function. The approach decouples the analysis of the solutions that can fulfil the operational constraints from the optimization and can be very effective in exploring the effect of several alternative cost functions on the optimal solution. Moreover, the shape of the Pareto front can offer a visual clue to the benefits offered by a hybrid storage compared to a single technology solution and on the optimization margins. The procedure is illustrated with a case of a full electric tugboat highlighting when a HESS can be beneficial and how the optimal design can be facilitated.Pareto-Based Design Optimisation of Hybrid Energy Storage Systems for Full-Electric VesselspublishedVersio
Preliminary Discussions from the Nordic Smart Building Initiative on the Definition of Smart Buildings
Full text linkSmart Buildings are defined more by their objectives, such as optimizing energy performance, sustainability, and occupant well-being, than by specific technologies. They incorporate advanced control systems, interoperable communication protocols, and adaptive, AI-driven automation to sense, interpret, and respond to changing indoor, outdoor, and user-related conditions. These buildings coordinate multiple subsystems (heating, cooling, lighting, ventilation, shading, etc.) to reduce energy costs, emissions, and peak demand while enhancing comfort, health, and productivity. International, European, and Nordic definitions share common features, with “Smart Buildings” becoming the preferred term over historical alternatives like “Intelligent Buildings.” The concept has evolved from automated to digitalized, then to intelligent, and finally to smart, characterized by supervisory, cross-system orchestration and two-way data exchange with energy grids, infrastructures, and occupants. Core features of Smart Buildings include occupant-centric and predictive control, continuous data analysis, interoperability, safety and security, energy flexibility, sustainability, predictive maintenance, and building-to-grid services. Minimum requirements include actuated systems, data collection and control infrastructure, adaptive strategies informed by multiple data sources, and user interfaces with bidirectional feedback. One should recognize that building smartness exists on a spectrum from basic to highly advanced implementations.Publishe
Client management in the project domain: towards conceptual integration using cross-disciplinary research
Full text linkClient management by the delivery organisation is under-researched across the project domain. Reviewing the literature positions client management (CM) as an important topic for improving performance. Three dominant theoretical strands are identified. One strand is based in the disciplines of marketing and organisational behaviour. It is largely located in the delivery firm. The second strand primarily locates CM as part of project marketing. This strand is rooted in operational management and has become positioned tactically as a subset of project management largely at the front-end. A lesser third strand views CM from the project management delivery perspective. The analysis demonstrates the theory-driven lenses employed by the different research strands produce a fragmented picture that limits current understanding. Hence there is a need for conceptual integration. The analysis argues for cross-disciplinary research to induce integration, commencing with the current intersections to create a strategic platform for generating new knowledge.publishedVersio
Strategic solar module stockpiling in the EU: A scenario-based analysis of costs and benefits beyond 2030
No full textWhat are the optimal levels of strategic solar module stockpiles in the European Union (EU) for achieving climate neutrality by 2050, and how might such stockpiles influence efforts to bolster domestic solar manufacturing and recycling industries? This paper addresses these questions, delving into the underexplored area of strategic reserves in renewable energy systems and offering actionable insights for policymakers to ensure stable solar PV deployment. Using an extended open-source energy system optimization model, 36 scenarios varying in energy costs, import dynamics, and economic factors were analyzed. The results indicate that stockpiling is cost-effective in only 8 scenarios, primarily under unfavorable import conditions. In scenarios with stockpiles, domestic manufacturing levels are, on average, lower and required later compared to scenarios without stockpiles. Stockpiles reduce import dependency by introducing temporal flexibility between module injection and withdrawal, effectively diversifying supply strategies. Additionally, they stabilize optimal wind capacities, underscoring their broader systemic role. The associated costs are modest, increasing by just 0.2 % in the reference scenario aligned with the latest Ten-Year Network Development Plan. Recycling and remanufacturing are not utilized in any scenario due to their higher costs compared to imports and EU manufacturing. From these findings, three policy recommendations emerge: (i) establish a strategic stockpile equivalent to three times the annual solar PV additions during the early 2030s, (ii) foster innovation in solar module recycling and remanufacturing in the meantime to build a resilient domestic industry, and (iii) monitor technological advancements to ensure the relevance and utility of stockpiled modules.Strategic solar module stockpiling in the EU: A scenario-based analysis of costs and benefits beyond 2030publishedVersio