As part of the transition towards a fully sustainable energy system, green hydrogen shows great potential to decarbonise several hard-to-abate sectors. To provide the fossil-free electricity required for electrolysis, offshore wind power has emerged as a suggested option. In this report, four scenarios using different electrolyser placements and technologies are compared and applied in a 30-year case study considering a 1 GW offshore wind farm in the Baltic Sea. The scenarios are evaluated through the optimisation of electrolyser capacities, full system modelling and simulation, a techno-economic assessment, as well as a literature review of technological readiness, safety aspects and operational considerations. It is shown that a range of installed capacities offers only slight differences in levelised costs and that the optimal sizes to a large part depend on future electrolyser cost developments. A 1:1 sizing ratio between electrolyser capacity and maximum available power is not suggested for any of the studied configurations. Further, the simulations indicate that electrolyser inefficiencies constitute 63.2–68.5% of the total energy losses. Power transmission losses are relatively small due to the short transmission distance, while the power demands of several subsystems are nearly insignificant. Onshore H2 production using an alkaline electrolyser system is highlighted, offering the highest system efficiency and largest hydrogen production, at 55.93% and 2.23 Mton, respectively. This setup is further shown to be the most cost-efficient, offering a levelised cost of hydrogen at 3.15 €/kgH2. However, obstacles in the form of social and environmental concerns and regulations are seemingly larger compared to the scenarios using offshore electrolysis. Further, rapid future cost developments for electrolysers are likely to strengthen the case for offshore and PEM electrolyser configurations. A range of research opportunities are highlighted to fill the identified knowledge gaps and enable further insights. / Como parte de la transicion hacia un sistema energético totalmente sostenible, el hidrógeno verde muestra un gran potencial para descarbonizar varios sectores en los que es difíciles de conseguir. La energía eólica marina ha surgido como una opción para suministrar la electricidad libre de fósiles necesaria para la electrólisis. En este informe se comparan y aplican cuatro escenarios que utilizan diferentes ubicaciones y tecnologías de electrolizadores en un estudio de caso a 30 aoñs que considera un parque eólico marino de 1 GW en el Mar Báltico. Los escenarios se evalúan mediante una optimización de la capacidad de los electrolizadores, la modelización y simulación de todo el sistema, una revisión bibliográfica de la disponibilidad tecnológica, teniendo en cuenta los aspectos de seguridad y las consideraciones operativas. Se demuestra que una gama de capacidades instaladas ofrece sólo ligeras diferencias en los costes nivelados y que los tamaños óptimos dependen en gran medida de la evolución futura de los costes de los electrolizadores. No se recomienda una relación de tamaño de 1:1 entre entre la capacidad del electrolizador y la potencia máxima disponible. Además, las simulaciones indican que las ineficiencias del electrolizador constituyen entre el 63,2% y el 68,5% de las pérdidas totales de energía. Las pérdidas de transmisión de energía son relativamente pequeñas debido a la corta distancia de transmisión, mientras que las demandas de energía de varios subsistemas son casi insignificantes. Destaca la producción de H2 en tierra utilizando un sistema de electrolizador alcalino, que ofrece la mayor eficiencia del sistema y la mayor producción de hidrógeno, con un 55,93% y 2,23 Mton respectivamente. Además, este sistema es el más rentable, con un coste nivelado del hidrógeno de 3,15 €/kgH2. Sin embargo, los obstáculos sociales, medioambientales y normativos parecen ser mayores que en el caso de la electrólisis en alta mar. Además, es probable que la rápida evolución de los costes de los electrolizadores refuerce las configuraciones de electrolizadores marinos y PEM. Se destacan en el documento una serie de oportunidades de investigación con el fin de completar el estado del arte identificado.

As part of the transition towards a fully sustainable energy system, green hydrogen shows great potential to decarbonise several hard-to-abate sectors. To provide the fossil-free electricity required for electrolysis, offshore wind power has emerged as a suggested option. In this report, four scenarios using different electrolyser placements and technologies are compared and applied in a 30-year case study considering a 1 GW offshore wind farm in the Baltic Sea. The scenarios are evaluated through the optimisation of electrolyser capacities, full system modelling and simulation, a techno-economic assessment, as well as a literature review of technological readiness, safety aspects and operational considerations. It is shown that a range of installed capacities offers only slight differences in levelised costs and that the optimal sizes to a large part depend on future electrolyser cost developments. A 1:1 sizing ratio between electrolyser capacity and maximum available power is not suggested for any of the studied configurations. Further, the simulations indicate that electrolyser inefficiencies constitute 63.2–68.5% of the total energylosses. Power transmission losses are relatively small due to the short transmission distance, while the power demands of several subsystems are nearly insignificant. Onshore H2 production using an alkaline electrolyser system is highlighted, offering the highest system efficiency and largest hydrogen production, at 55.93% and 2.23 Mton, respectively. This setup is further shown to be the most cost-efficient, offering a levelised cost of hydrogen at 3.15 €/kgH2. However, obstacles in the form of social and environmental concerns and regulations are seemingly larger compared to the scenarios using offshore electrolysis. Further, rapid future cost developments for electrolysers are likely to strengthen the case for offshore and PEM electrolyser configurations. A range of research opportunities are highlighted to fill the identified knowledge gaps and enable further insights. / Como parte de la transición hacia un sistema energético totalmente sostenible, el hidrógeno verde muestra un gran potencial para descarbonizar varios sectores en los que es difíciles de conseguir. La energía eólica marina ha surgido como una opción para suministrar la electricidad libre de fósiles necesaria para la electrólisis. En este informe se comparan y aplican cuatro escenarios que utilizan diferentes ubicaciones y tecnologías de electrolizadores en un estudio de caso a 30 años que considera un parque eólico marino de 1 GW en el Mar Báltico. Los escenarios se evalúan mediante una optimización de la capacidad de los electrolizadores, la modelización y simulación de todo el sistema, una revisión bibliográfica de la disponibilidad tecnológica, teniendo en cuenta los aspectos de seguridad y las consideraciones operativas. Se demuestra que una gama de capacidades instaladas ofrece sólo ligeras diferencias en los costes nivelados y que los tamaños óptimos dependen en gran medida de la evolución futura de los costes de los electrolizadores. No se recomienda una relación de tamaño de 1:1 entre entre la capacidad del electrolizador y la potencia máxima disponible. Además, las simulaciones indican que las ineficiencias del electrolizador constituyen entre el 63,2% y el 68,5% de las pérdidas totales de energía. Las pérdidas de transmisión de energía son relativamente pequeñas debido a la corta distancia de transmisión, mientras que las demandas de energía de varios subsistemas son casi insignificantes. Destaca la producción de H2 en tierra utilizando un sistema de electrolizador alcalino, que ofrece la mayor eficiencia del sistema y la mayor producción de hidrógeno, con un 55,93% y 2,23 Mton respectivamente. Además, este sistema es el más rentable, con un coste nivelado del hidrógeno de 3,15 €/kgH2. Sin embargo, los obstáculos sociales, medioambientales y normativos parecen ser mayores que en el caso de la electrólisis en alta mar. Además, es probable que la rápida evolución de los costes de los electrolizadores refuerce las configuraciones de electrolizadores marinos y PEM. Se destacan en el documento una serie de oportunidades de investigacin ócon el fin de completar el estado del arte identificado.

The object of this thesis is to develop a cost effective direct-driven wind generator suited for offshore wind turbines. As the generator price is a complicated function dependent on many parameters, the emphasis is mainly put on reduction of the weight of active materials, such as copper, laminated steel, permanent magnets, and electrical insulation. The higher specific torque and power density of a transverse flux permanent magnet (TFPM) machine in comparison to conventional radial-flux machines make it a promising solution for direct-driven wind turbine generators. The novel TFPM generator investigated in this work due to its possibly more compact construction would allow a better utilization of the available nacelle space. The analytical model, including evaluation of the synchronous inductance, is developed and applied in parametric study of a 5 MW wind turbine generator. The influence of the design variables with respect to the analyzed characteristics is investigated. A number of machines that have approximately the same performances are found. These machines are compared and the optimal ranges for the main parameters are suggested. One possible design topology is presented in more details with dimensions and main characteristics. This generator is compared with radial-flux generators with surface-mounted and tangentially-polarized magnets. It is found that the analyzed TFPM generator would favor a smaller outer diameter, reduced total active weight, and reduced weight of the magnet material. The TFPM would however require a longer axial length. TFPM generators with a broader range of output power have also been investigated. Generators rated 3, 5, 7, 10, and 12 MW are analyzed and their characteristics with respect to the output power are compared. The novel transverse flux topology has been found to be promising for low-speed hightorque applications, such as direct-driven wind turbines in the multi-megawatt range. / QC 20101118

The ocean has tremendous potential in terms of energy generation, and wave energy is especially promising. However, wave energy technology is still non-commercial. Along with ambitious renewable energy targets and investments, much is happening within the field and the wave energy converter developers CorPower Ocean intend to have their technology proven in the upcoming years. This study aims at investigating the value of commercial wave energy in an energy system. This is fulfilled by the possibilities of achieving 24/7 Carbon-free Energy with the wave energy technology from CorPower Ocean at the stage of commercialization. An energy system is modeled with wave energy, floating offshore wind energy, lithium-ion battery storage and the Portuguese national grid, supplying Northvolt’s and Galp’s future lithium conversion facility in Portugal. Different system configurations are compared based on three Key Performance Indicators: 24/7 Carbon-free Energy performance, system emission, and cost for the electricity consumer. In addition, a review of available financial support mechanisms for renewable energy technologies and especially wave energy is done to understand how such mechanisms can affect the economic feasibility of the energy system modeled. The wave energy technology from CorPower Ocean shows to have a high power output and 24/7 carbon-free Energy performance in this study. Although a combination of wave and floating offshore wind energy better ensure energy security with generation profiles that peak at different times, the modeling shows that a system with wave energy alone is preferred for supplying the facility with electricity both from an environmental and economic perspective. The economic feasibility of Lithium-ion battery storage in the system is uncertain and to achieve 24/7 Carbon-free Energy supply of the facility a longer duration storage solution is needed. The price for wave energy in this study is higher than for other commercial renewable energy technologies such as solar PV. However, based on the available financial support structures from governments and other stakeholders, wave energy technology has the potential to be competitive as soon as the technology is proven. / Energigenerering från våra hav har stor potential, inte minst från vågkraft. Trots att vågkraftstekniken ännu inte har nått ett kommersiellt stadie händer det mycket inom området i takt med fler ambitiösa miljökrav och investeringar. CorPower Ocean utvecklar vågkraftsteknik och planerar att ha sin teknik bevisad inom några år. Den här studien syftar till att undersöka värdet av kommersiell vågkraft, vilket uppfylls genom möjligheterna till förnybar el 24 timmar om dygnet med CorPower Ocean’s vågenergiomvandlare. Ett energisystem modelleras med vågkraft, flytande vindkraft, litium-jon batterier och det portugisiska elnätet för att försörja Northvolts och Galps planerade anläggning för litiumkonvertering i Portugal. Olika systemkonfigurationer är jämförda utifrån tre parametrar: 24/7 förnybar el prestation, systemutsläpp och elkostnad för konsumenten. I tillägg utförs en studie om vilka finansiella supportmekanismer som finns för hållbar energiteknik och speciellt för utvecklingen av vågkraft. Detta för att få insikt i om vågkraft kan få finansiellt stöd och konkurrera med andra förnybara energitekniker. Studien visar att vågkraftstekniken presenterar bra utifrån de tre parametrarna. Trots att en kombination av våg och flytande vindkraft ger bättre elsäkerhet med alternerande produktionskurvor visar modelleringen att ett system med endast vågkraft är att föredra både från ett ekonomiskt och ett miljöperspektiv. En investering av litium-jon batterier i energisystemet är tveksam och för att uppnå förnybar elförsörjning av anläggningen 24 timmar om dygnet krävs en energilagringsteknik som möjliggör lagring över längre perioder. Priset för vågkraft i studien är högre än för andra kommersiella förnybara energitekniker så som solpaneler. Baserat på det finansiella stöd som finns från myndigheter och andra intressenter så är det möjligt för vågkraften att bli konkurrenskraftig så fort tekniken är bevisad.

Multiline anchors are a novel way to reduce the cost of arrays of floating offshore wind turbines (FOWTs), but their behavior is not yet fully understood. Through metocean characterization and dynamic simulations, this thesis investigates the effects of wind-wave misalignment on multiline anchor systems. Four coastal U.S. sites are characterized in order to develop IEC design load cases (DLCs) and analyze real-world misaligned conditions. Stonewall Bank, Oregon showed the highest 500-year extreme wave height, at 16.6 m, while Virginia Beach, Virginia showed the highest 500-year wind speed, at 56.8 m/s. Misalignment probability distributions, at all sites, are found to converge towards zero (aligned conditions) and become less variable as wind speed increases. This indicates that high misalignment angles are unlikely at high wind speeds. A simulation parameter study, spanning a range of wave directions, misalignment angles, and DLCs, is run in OpenFAST to explore how misalignment affects multiline anchor loading. The simulated anchor is connected to three IEA 15 MW FOWT models via a taut mooring system. The force on the multiline anchor is calculated by summing the three tension vectors from the mooring lines. The mean direction of this force is found to align closely with the wind; each mean is within 5.5° of the wind direction. Higher misalignment angles cause increases to the amount of directional variation about this mean. The magnitude of the multiline force is also examined. Mean force level is found to be nearly unaffected by misalignment. However, maximum force decreases significantly as misalignment angle increases, dropping as much as 23.3% in extreme conditions. This confirms current anchor design practice, which treats aligned metocean conditions as the peak load an anchor experiences. Standard deviation of multiline force also decreases with misalignment. The operational load case, DLC 1.6, shows a slight trend towards this, but the extreme case, SLC, shows a more pronounced drop of 32.4%. This suggests that anchor cyclic loading analyses could benefit from considering misalignment. Doing so could lead to lower estimates of the cyclic loading amplitudes that anchor designs must withstand, thus leading to smaller, cheaper anchors.

This thesis examines the pivotal role of port infrastructure in supporting offshore wind project development, with a focus on the strategic significance of port operation and storage. This study addresses the challenges of evaluating port area demand, complicated by the intricate and dynamic nature of the construction and logistical operations associated with offshore wind development. Through a comprehensive approach that includes a literature review on diverse roles of ports, analysis of port operations for key turbine components, and formulation of an assessment model to estimate port area demand, this research offers insights into the logistical and operational needs of ports in the offshore wind sector. A significant highlight of this study is the consideration of the temporal influence on port demand, a crucial factor stemming from the continuous loading and unloading activities at the port. In addition to port terminal area, hard criteria such as water depth, quay length, and load-bearing capacity are also examined. The findings underscore the connection between port infrastructure and the efficient operation of offshore wind farms. It highlights the need for synchronized coordination between the transport rate of components and offshore installation activities, to meet the specific demands of port infrastructure. Furthermore, the thesis explores these findings in the context of port development, identifying key requirements, challenges, and opportunities within the sector and offering a forward-looking perspective on the industry. This perspective considers the emerging trends, technological advancements, and innovative practices in offshore wind and their implications for port development. In conclusion, the research emphasizes the critical importance of understanding and meeting port specification requirements for the successful execution of offshore wind projects. It calls for continuous research and development efforts to improve the accuracy of estimating port infrastructure enhancement needs, in support of the growing offshore wind industry.

Cost efficient operation and maintenance strategies are crucial for reducing cost of wind energy. Since the regime change from feed-in tariffs to an auction-based bidding system for capacity in most European wind projects, levelized cost of energy is challenged constantly. Therefore, new technologies such as new controllers are developed to improve operation and to increase profit. Previous research studies demonstrated the advantage of increased power output of wake redirection control. However, understanding and quantifying the impact of wind farm control technologies on operation and maintenance strategies is inevitable to evaluate the economic feasibility of such new technologies. Thus, an event-based O&M simulation tool has been developed. Besides general modules, such as the wind turbine model, the weather forecasting model and a model for simulating corrective and planned maintenance, the developed tool also takes wake effects into account. This allows considering different power productions for each individual turbine and a failure rate distribution within the wind farm which is based on altering loads on the different components. Both aspects are driven by changes in operation when applying a new controller technology. Exemplarily, the economic feasibility of a closed-loop active wake steering control has been analysed. Main achievements of this study are the possibility to quantify the impact of the active wake steering control on O&M related KPIs. Results show that additional loads caused by applying yaw-misalignment and redirecting wake, lead to an increase in OPEX. However, the achieved energy production gain and thus related additional revenue exceeds additional cost in the case study. Nonetheless, the study reveals that the profitability of the controller is highly dependent on the electricity price which can be acquired during the wind farm’s lifetime.

Nas últimas décadas, a fonte eolielétrica é a que sinaliza maior crescimento mundial dentre as demais. A curva de aprendizagem tecnológica do setor mostra queda do custo entre 15% a 20% a cada 3 anos. Países ativos no setor eólico se esforçam pela meta de 12% de participação na produção elétrica mundial em 2020. A contribuição da geração eolielétrica offshore é fundamental para essa meta, pela proximidade aos centros de carga, com ganhos de eficiência, de escala e reduzido impacto ambiental e visual. Apesar do crescimento do parque gerador nacional em 2006, há carência na produção no curto prazo. Contraditoriamente, há ventos abundantes para geração eolielétrica e o prévio arcabouço industrial que seria necessário para desenvolver o setor. Apesar do incentivo governamental (PROINFA), o setor eólico brasileiro ainda não decolou como esperado. O objetivo deste trabalho é reforçar o debate sobre a importância da diversificação da matriz, em prol da estratégia de segurança do suprimento energético nacional e da redução da emissão de gases de efeito estufa. Em rumo a esse objetivo, são colocados argumentos com abordagem ampla e com abordagem específica. Na abordagem ampla, esta pesquisa propõe uma maior inserção da fonte eólica na matriz elétrica nacional como uma das opções a serem consideradas de maneira mais relevante nas táticas de diversificação da matriz, a exemplo do que já fazem países com maior abundância de gás natural que o Brasil, como o Reino Unido. Sob um ponto de vista específico, a investigação exemplifica possibilidades de contribuição da fonte eolielétrica, na sua versão offshore, para as táticas de diversificação da matriz nacional que se entendem importantes, a exemplo do já fazem países com maior predominância da fonte hidráulica que o Brasil, como a Noruega. O método utilizado para se alcançar o objetivo desta dissertação envolve os seguintes passos: (1) esclarecer quanto aos principais aspectos do setor energético a nível mundial e o problema ambiental que está vinculado à produção de energia por fontes fósseis; (2) esclarecer quanto aos aspectos do desenvolvimento de sistemas eolielétricos onshore no Brasil e no mundo e também do desenvolvimento de sistemas offshore em países de interesse; (3) explorar exemplos de articulação dos sistemas eólicos offshore com projetos de produção de energia fóssil em ambiente marítimo, como forma de produzir sinergia útil a ambos os setores; (4) analisar e debater sobre as propostas do governo brasileiro para o futuro da matriz elétrica do país; (5) propor algumas possibilidades de desenvolvimento de sistemas eólicos offshore no Brasil, partindo de pequenos projetos-piloto. Caso as propostas deste trabalho se tornem realizadas, os resultados para este país líder em energia limpa e renovável seriam: a criação de valor nas operações offshore de produção de energia fóssil, o ganho de aprendizagem sobre a tecnologia eólica, o alívio parcial da oferta energética para centros litorâneos no curto prazo; a racionalização do uso, transporte e dependência externa do gás natural; a dinamização dos Mecanismos de Desenvolvimento Limpo (CDM / MDL) e de novos mercados e empregos para a indústria. / In the last decade wind power source was the fastest-growing energy source. Technological learning curves for this sector fall down by a 15% a 20% rate each 3 years. Countries which are committed with wind power are running after the target of 12% wind into the worlds electrical production by 2020. The contribution of the offshore wind power (OWP) source is fundamental on covering such target, due to the proximity to load centers, efficiency & scale savings and reduced environmental and visual impact. Although the growth of the Brazilian power generation system in 2006, there is a gap on fulfilling demand in the short run. Nevertheless, Brazil has abundance of winds suitable for power generation, as a previous industrial framework, necessary on developing this sector. Even that a governmental program has come (PROINFA), wind power sector has not risen as expected yet. The goal of this thesis is to reinforce the debate about the importance on diversifying the Brazilian power matrix, towards the strategy of energy security supply as the reduction of greenhouse gases emissions. On reaching such a goal, this thesis states arguments by a generic approach and also by a specific approach. In the generic approach, it proposes a larger share for wind into the Brazilian electrical matrix as one of the options that should be considered in a more relevant manner for the tactics of diversifying the electrical matrix, following the example given by countries with larger abundance than Brazil regarding on natural gas production, as it is the case of the United Kingdom. In the specific approach, this investigation exemplifies possibilities of contributions from the OWP for the tactics of diversifying the matrix, following the example given by a country with higher predominance than Brazil regarding on using large hydropower as the main national power source, which is the case of Norway. The method taken for reaching the thesis goal involves the following steps: (1) to clarify on some aspects regarding energy production and its respective environmental problem related to the greenhouse gases emissions;(2) to clarify some aspects about the development of wind energy systems in Brazil and in the world and also some aspects about the development of OWP projects in selected countries; (3) to explore examples of articulation between OWP systems with offshore fossil energy production systems, in order to argue about the synergy that is possible between them; (4) to analyze and debate about the Brazilian governments proposal for the electrical matrix in the long run; (5) to propose some possibilities of developing OWP systems in Brazil, starting by small-scale pilot projects. If the case the propositions of this thesis come true in the future, the earnings for this country, which a world leader in clean & renewable energy, would be the following: value creation into the offshore fossil energy production; growth of learning about the OWP technologies; the partial relief of power supply for the coastal load centers; rationalization on the use, transport and foreign dependence of natural gas resources; pushing dynamics for Clean Development Mechanisms (CDM), as for industrial markets and employment.

Durch die Zunahme von Offshorewindparks wird der anthropogene Lärmpegel im Meer weiter ansteigen. Deshalb ist es notwendig, mögliche negative Effekte von Windturbinenschall auf Fische zu erkennen und zu minimieren. Um mögliche Effekte des Turbinenschalls auf Kabeljau (Gadus morhua) und Scholle (Pleuronectes platessa) zu untersuchen, wurden die Fische in Laborversuchen verschiedenen tiefen Frequenzen und Schallstärken, wie sie von Windturbinen emittiert werden ausgesetzt. Ein ringförmiges Betonversuchsbecken mit 10 Metern Durchmesser wurde mit Schallisolationwänden in verbundene Viertel unterteilt, wodurch im Becken eine Schalldruckdifferenz von 32-52 dB, abhängig von Frequenz und produziertem Schalldruckpegel erzeugt wurde. Die Fische, die sich frei im Becken bewegen und so, wenn sie wollten, den höchsten Schalldruckpegeln ausweichen konnten, wurden monofrequenten Tönen im Frequenzbereich zwischen 25 und 250 Hz in Schalldruckpegeln von 130 und 140 dB re 1 µPa ausgesetzt. Die Position der Fische im Becken wurde in den 24-Stunden-Phasen vor, während und nach Beschallung verglichen und zeigte in den meisten Versuchen während Beschallung signifikant weniger Kabeljau in der Nähe der Schallquelle, als in den Phasen vor und nach Beschallung. Scholle zeigte uneinheitliche Reaktionen, die teilweise auf Meideverhalten, in anderen Versuchen auf Attraktion durch den Schall hindeuteten. Die Ergebnisse lassen wenigstens kurzzeitige, durch Schall verursachte Verteilungsänderungen von Kabeljau in Offshorewindparks erwarten. / The growing number of offshore wind farms will lead to an increase of anthropogenic noise in the sea. Research is therefore necessary to identify and minimize any potentially negative effects of offshore wind turbine noise on fish. To examine the potential impact of offshore wind farm noise emissions on cod (Gadus morhua) and plaice (Pleuronectes platessa), tank experiments were carried out exposing the fishes to different low frequencies at sound levels as emitted by wind turbines An annular concrete tank of 10 m in diameter was divided in connected quarters by sound barriers, so that sound pressure differences of 32 to 52 dB were achieved, depending on frequency and produced sound levels. Pure tones in the frequency range between 25 and 250 Hz were artificially emitted in sound levels of 130 and 140 dB re 1µPa. The experimental fish were free to move around in the tank and therefore could avoid the highest sound levels if they chose to. The location of fish in the 24 hour periods before, during and after sound production were compared and showed significantly lower numbers of cod in the vicinity of the sound source during sound presentation in the majority of the experiments. Reactions of plaice were ambiguous, suggesting both avoidance of, or attraction to the sound. From the results at least short-term changes in distribution of cod related to sound in the vicinity of offshore wind farms could be expected.

Les politiques de développement durable ont fait émerger de nombreux outils qui visent à concilier les enjeux de développement économique et ceux de préservation des intérêts sociaux et environnementaux. Parmi eux, la compensation territoriale se matérialise par l’attribution, à un territoire subissant les impacts négatifs d’un aménagement déclaré d’utilité publique, d’un ensemble de mesures visant à maintenir à niveau acceptable le bien-être des individus et l’état écologique du milieu. Elle permet ainsi de rétablir un équilibre entre la dimension globale du projet, qui ne considère que ses effets positifs, et la dimension locale, dans laquelle les externalités positives et négatives du projet rentrent en jeu. Initié par un questionnement sur la mise en oeuvre d’un tel outil de politique publique au sein de territoires spécifiques, l’objectif principal de ce travail est de caractériser la demande de compensation par les acteurs du territoire au regard des impacts perçus dans un contexte de projet d’aménagement. Ce travail explore les perceptions des acteurs du territoire de la baie de Saint-Brieuc directement concernés par un projet de parc éolien en mer vis-à-vis de ce principe de compensation. Pour ce faire, des approches qualitatives et quantitatives ont été utilisées de manière complémentaire et font appel à des outils spécifiques tels que la cartographie cognitive floue et la méthode des choix expérimentaux. Cette démarche nous a permis de produire de nombreux éléments de compréhension quant à la manière dont ces acteurs perçoivent les impacts d’un tel projet d’aménagement, acceptent ou non le principe de compensation comme outil de réponse aux impacts négatifs du projet et envisagent la mise en oeuvre de la compensation à travers leurs préférences vis-à-vis de différentes types d’actions – indemnisations financières, investissements dans des biens communs, restauration écologique. Les résultats de ce travail montrent que les perceptions, très hétérogènes au sein des acteurs du territoire, s’expliquent en grande partie à travers le concept de Communautés de Pratiques. Finalement, lorsque le principe de compensation est accepté par les acteurs du territoire, la logique d’équivalence qui conditionne la demande de compensation peut s’expliquer de trois manières différentes : une équivalence territoriale dans laquelle les bénéfices issus de la compensation doivent profiter à l’ensemble de la population du territoire impacté ; une équivalence écologique dans laquelle le niveau de fonctions écologiques et de services écosystémiques est maintenu constant, une équivalence basée sur des valeurs économiques pour pallier le manque à gagner de certaines activités professionnelles. / In the context of a territory suffering from the negative impacts of an infrastructure declared of public utility, territorial compensation consists of a set of measure that aims to help maintaining the level of well-being of each and every individual as well as a desirable ecological state. This way, territorial compensation allows to balance between the global scale of the project, in which only the positive impacts are taken into account, and the local scale where both positive and negative externalities of the project are running. Initiated by a questioning on how such a public policy tool can be deployed at the heart of specific territories, the main objective of this PhD work is to characterize the expectation of local stakeholders towards the perceived impacts awaited from the instatement of a development project. More specifically, this work relies on an analytical approach centered on the study of the perception of the stakeholders of the Bay of St-Brieuc territory (Western Brittany, France), who are directly concerned by an offshore wind farm project. To reach suchaims, complementary qualitative and quantitative methods are used such as fuzzy cognitive mapping and choice experiment method. Using this kind of approaches allowed us to better define several keys for understanding how local stakeholders perceive the impacts of such a project and agree or not with compensation being an appropriate answer regarding the negative impacts of the project and consider the implementation of compensation in reference to their preferences towards different types of action – monetary incentives, public goods investments, ecological restoration. Our results show very heterogeneous perceptions in between the different stakeholders that can in a large part beexplained using the concept of Communities of Practice. Finally, when the principle of compensation is accepted by allthe stakeholders of a territory, the equivalency logical that determines the compensation expectations can be of three types: a territorial equivalency, in which the benefits of compensation must be shared by all inhabitants of the impacted territory; an ecological equivalency, in which the level of ecological functions or ecosystem services is maintained constant; and an equivalency based on economic values that must balance the loss of benefits underwent by some professional activities.