• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 11
  • 2
  • Tagged with
  • 13
  • 11
  • 10
  • 9
  • 9
  • 9
  • 7
  • 7
  • 6
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A TECHNO-ECONOMIC FEASIBILITY STUDY OF OFFSHORE WIND-HYDROGEN PRODUCTION IN SOUTHERN SWEDEN

Hansson, Carol January 2022 (has links)
To meet the energy targets and improve the lack of power and higher prices in southern Sweden, the amount of electricity must increase, and alternative fuel sources be introduced. This thesis examines the techno-economic feasibility of offshore wind-hydrogen production in southern Sweden, depending on whether an onshore- or offshore hydrogen system is used, and how grid connection subsidies would affect this. New research and development regarding the subjects were analyzed and reviewed. A project that has currently applied for a permit in southern Sweden, Skåne Offshore Wind Park, was used as a case study where the information from the review and data from similar parks were used to determine the cost and production for the two different systems. The costs were then adjusted according to the three different subsidy scenarios: current with no subsidies, partial with sea cable and transformer costs removed, or a full subsidy scenario where only the internal grid cost remained to achieve feasible levelized costs for electricity and hydrogen based on a discount rate of 6% and a lifetime of 25 years. Finally, a sensitivity analysis was performed.   The results showed that market competitive electricity prices are only achieved with an onshore hydrogen system- and only if a full subsidy is introduced or if a best-case scenario is applied. In a worst-case scenario, no competitive electricity prices were achieved. For the offshore hydrogen system, the extra fuel system is too inefficient for electricity production. For hydrogen, prices were achieved within a reasonable price range of green hydrogen for all scenarios, where the onshore hydrogen system was 4% more advantageous. In a best-case scenario, competitive values ​​even against blue hydrogen were achieved for the offshore hydrogen systems and for the full subsidy onshore hydrogen system. For hydrogen, the offshore hydrogen system's hydrogen prices were competitive regardless of subsidies, however this system had the highest CAPEX and OPEX costs.   The results of the study underline the need for fixed conditions but also the necessity of introducing a full subsidy for the grid connection cost - or best-case scenario conditions - to encourage further offshore wind power development.
12

SWOT-PESTEL Study of Constraints to Decarbonization of the Natural Gas System in the EU Techno-economic analysis of hydrogen production in Portugal : Techno-economic analysis of hydrogen production in Portugal

VASUDEVAN, ROHAN ADITHYA January 2021 (has links)
The exigent need to address climate change and its adverse effects is felt all around the world. As pioneers in tackling carbon emissions, the European Union continue to be head and shoulders above other continents by implementing policies and keeping a tab on its carbon dependence and emissions. However, being one of the largest importers of Natural Gas in the world, the EU remains dependent on a fossil fuel to meet its demands.  The aim of the research is to investigate the barriers and constraints in the EU policies and framework that affects the natural gas decarbonization and to investigate the levelized cost of hydrogen production (LCOH) that would be used to decarbonize the natural gas sector. Thus a comprehensive study, based on existing academic and scientific literature, EU policies, framework and regulations pertinent to Natural gas and a techno economic analysis of possible substitution of natural gas with Hydrogen, is performed. The motivation behind choosing hydrogen is based on various research studies that indicate the importance and ability to replace to natural gas. In addition, Portugal provides a great environment for cheap green hydrogen production and thus chosen as the main region of evaluation.  The study evaluates the current framework based on a SWOT ((Strength, Weakness, and Opportunities & Weakness) analysis, which includes a PESTEL (Political, Economic, Social, Technological, Environmental & Legal) macroeconomic factor assessment and an expert elicitation. The levelized cost of hydrogen is calculated for blue (SMR - Steam Methane Reforming with natural gas as the feedstock) and green hydrogen (Electrolyzer with electricity from grid, solar and wind sources). The costs were specific to Portuguese conditions and for the years 2020, 2030 and 2050 based on availability of data and the alignment with the National Energy and Climate Plan (NECP) and the climate action framework 2050. The sizes of Electrolyzers are based on the current Market capacities while SMR is capped at 300MW. The thesis only considers production of hydrogen. Transmission, distribution and storage of hydrogen are beyond the scope of the analysis.  Results show that the barriers are mainly related to costs competitiveness, amendments in rules/regulations, provisions of incentives, and constraints in the creation of market demand for low carbon gases. Ensuring energy security and supply while being economically feasible demands immediate amendments to the regulations and policies such as incentivizing supply, creating a demand for low carbon gases and taxation on carbon.  Considering the LCOH, the cheapest production costs continue to be dominated by blue hydrogen (1.33 € per kg of H2) in comparison to green hydrogen (4.27 and 3.68 € per kg of H2) from grid electricity and solar power respectively. The sensitivity analysis shows the importance of investments costs and the efficiency in case of electrolyzers and the carbon tax in the case of SMR. With improvements in electrolyzer technologies and increased carbon tax, the uptake of green hydrogen would be easier, ensuring a fair yet competitive gas market. / Det starka behovet av att ta itu med klimatförändringarna och deras negativa effekter är omfattande världen över. Den europeiska unionen utgör en pionjär när det gäller att såväl hantera sina koldioxidberoende och utsläpp som att implementera reglerande miljöpolitik, och framstår därmed som överlägsen andra stater och organisationer i detta hänseende. Unionen är emellertid fortfarande mycket beroende av fossilt bränsle för att uppfylla sina energibehov, och kvarstår därför som en av världens största importörer av naturgas.  Syftet med denna forskningsavhandling är att undersöka befintliga hinder och restriktioner i EU: s politiska ramverk som medför konsekvenser avkolningen av naturgas, samt att undersöka de utjämnande kostnaderna för väteproduktion (LCOH) som kan användas för att avkolna naturgassektorn. Därmed utförs en omfattande studie baserad på befintlig akademisk och vetenskaplig litteratur, EU: s politiska ramverk och stadgar som är relevanta för naturgasindustrin. Dessutom genomförs en teknisk-ekonomisk analys av eventuella ersättningar av naturgas med väte. Valet av väte som forskningsobjekt motiveras olika forskningsstudier som indikerar vikten och förmågan att ersätta till naturgas. Till sist berör studien Portugal. som tillhandahåller en lämplig miljö för billig och grön vätgasproduktion. Av denna anledning är Portugal utvalt som den viktigaste utvärderingsregionen.  Studien utvärderar det nuvarande ramverket baserat på en SWOT-analys ((Strength, Weakness, and Opportunities & Weakness), som inkluderar en PESTEL (Political, Economical, Social, Technological, Environmental och Legal) makroekonomisk faktoranalys och elicitering. Den utjömnade vätekostnaden beräknades i blått (SMR - Ångmetanreformering med naturgas som råvara) och grönt väte (elektrolyser med el från elnät, sol och vindkällor). Kostnaderna var specifika för de portugisiska förhållandena under åren 2020, 2030 och 2050 baserat på tillgänglighet av data samt anpassningen till den nationella energi- och klimatplanen (NECP) och klimatåtgärdsramen 2050. Storleken på elektrolyserar baseras på den nuvarande marknadskapaciteten medan SMR är begränsad till 300 MW. Avhandlingen tar endast hänsyn till produktionen av vätgas. Transmission, distribution och lagring av väte ligger utanför analysens räckvidd.  Resultaten visar att hindren är främst relaterade till kostnadskonkurrens, förändringar i stadgar och bestämmelser, incitament och begränsningar i formerandet av efterfrågan på koldioxidsnåla gaser på marknaden. Att säkerställa energiförsörjning och tillgång på ett ekonomiskt hållbart sätt kräver omedelbara ändringar av reglerna och politiken, såsom att stimulera utbudet, att skapa en efterfrågan på koldioxidsnåla gaser och genom att beskatta kol.  När det gäller LCOH dominerar blåväte beträffande produktionskostnaderna (1,33 € per kg H2) jämfört med grönt väte (4,27 respektive 3,68 € per kg H2) från elnät respektive solenergi. Osäkerhetsanalysen visar vikten av investeringskostnader och effektiviteten vid elektrolysörer och koldioxidskatten för SMR. Med förbättringar av elektrolys-tekniken och ökad koldioxidskatt skulle upptagningen av grön vätgas vara enklare och säkerställa en rättvis men konkurrenskraftig gasmarknad.
13

Hydrogen Production and Storage Optimization based on Technical and Financial Conditions : A study of hydrogen strategies focusing on demand and integration of wind power. / Optimering av vätgasproduktion och lagring utifrån tekniska och ekonomiska förutsättningar : En studie av vätgasstrategier med fokus på efterfrågan och integration av vindkraft.

Langels, Hanna, Syrjä, Oskar January 2021 (has links)
There has recently been an increased interest in hydrogen, both as a solution for seasonal energy storage but also for implementations in various industries and as fuel for vehicles. The transition to a society less dependent on fossil fuels highlights the need for new solutions where hydrogen is predicted to play a key role. This project aims to investigate technical and economic outcomes of different strategies for production and storage of hydrogen based on hydrogen demand and source of electricity. This is done by simulating the operation of different systems over a year, mapping the storage level, the source of electricity, and calculating the levelized cost of hydrogen (LCOH). The study examines two main cases. The first case is a system integrated with offshore wind power for production of hydrogen to fuel the operations in the industrial port Gävle Hamn. The second case examines a system for independent refueling stations where two locations with different electricity prices and traffic flows are analyzed. Factors such as demand, electricity prices, and component costs are investigated through simulating cases as well as a sensitivity analysis. Future potential sources of income are also analyzed and discussed. The results show that using an alkaline electrolyzer (AEL) achieves the lowest LCOH while PEM electrolyzer is more flexible in its operation which enables the system to utilize more electricity from the offshore wind power. When the cost of wind electricity exceeds the average electricity price on the grid, a higher share of wind electricity relative to electricity from the grid being utilized in the production results in a higher LCOH. The optimal design of the storage depends on the demand, where using vessels above ground is the most beneficial option for smaller systems and larger systems benefit financially from using a lined rock cavern (LRC). Hence, the optimal design of a system depends on the demand, electricity source, and ultimately on the purpose of the system. The results show great potential for future implementation of hydrogen systems integrated with wind power. Considering the increased share of wind electricity in the energy system and the expected growth of the hydrogen market, these are results worth acknowledging in future projects.

Page generated in 0.0244 seconds