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  • 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.
91

Commercialization possibilities of Stirling engine technology for microscale power generation in Sweden / MicroStirling : Business plan

Backman, Peter January 2012 (has links)
The presented master’s thesis has evaluated the possibility of commercializing a research project at the Royal Institute of Technologys (KTH) Department of Energy Technology (EGI) in Stockholm, Sweden, where a Stirling engine is used for renewable microscale power generation.  The purpose of the thesis has been to evaluate the current market situation and future prospects by composing a business plan under the working name MicroStirling. In the business plan a potential target group consisting of house owners, farming companies and small energy-intensive industries has been identified. The market is currently small but displaying tremendous possibilities and is likely to grow rapidly in coming years. By offering a unique, high quality product MicroStirling has a competitive edge; however, several risks threaten the success of the company. Market readiness and customer acceptance of the technology are significant market barriers. Short term focus should be concentrated on technology development to prepare for pilot projects in 2013 and a market introduction in 2014. A future successful commercialisation of the technology is viable although further technical and business development is required to finalize a product ready for a market introduction. / EXPLORE Polygeneration
92

TECHNO-ECONOMIC ANALYSIS OFRENEWABLE GAS PRODUCTION AND ELECTRICITY GENERATION FROM ORGANIC WASTE : A Feasibility Study of a Conceptual Biogas Plant in the Santander Region, Colombia

Sassersson Busadee, Nelly, Ahmed, Laura January 2023 (has links)
Strategies to harness the energy from organic waste is gaining importance on a global scale, especially in countries with large quantities of it. In this paper, a techno-economic analysisand a field study were performed to investigate the feasibility of five scenarios for a conceptual biogas facility, based on a case study from Colombia. The plant designs involved anaerobic digestion followed by different combinations of biogas upgrading, combined heat and power and/or steam methane reforming technologies and investigated four different feedstocks. The results demonstrated that the road infrastructure leading to the current proposed site is inadequate, and a new location should be found. Anaerobic digestion alone was most profitable with the shortest payback period. Organic Municipal Solid Waste and Poultry Manure produced high techno-economic potential depending on the scenario. The production of hydrogen using anaerobic digestion, steam methane reforming and combined heat and power with or without upgrading is not recommended due to the current market prices and high heat consumption. However, it can be profitable to implement green energy initiatives as a strategy to establish and lead future energy markets.
93

Techno-Economic Analysis of Parabolic Trough Collectors : A case study for two industrial parks in Zhejiang, China / Tekno-ekonomisk analys av decentraliserade Solfångare : En fallstudie av två industriella parker i Zhejiang, Kina

Lemaitre, Emile, Peri, Michael January 2019 (has links)
Transitioning the industrial sector’s energy system to renewable sources is crucial to reduce climate change. There is no exception for China, currently having the highest absolute levels of greenhouse gas (GHG) emissions in the world. The industrial sector accounts for about two thirds of the national energy consumption and coal is the country’s most important energy source. The integration of alternative energy sources such as solar can help transitioning the country’s energy system. By presenting a techno-economic analysis, this thesis gives an indication for profitability and in what extent there is a potential to cover the steam demand with a decentralized solar heat technology for two industries, fish and textile, in the Zhejiang province in eastern China. The used solar technology is a system with parabolic trough collectors (PTCs) with an integrated gas fired boiler. The PTC-system is compared with a coal-fired centralized supplier. The analyzed factors were roof area, solar irradiation, solar fraction, cost for steam from the centralized suppliers and cost of coal and natural gas. The maximum CO2 reduction is found to be dependent on the potential installation area. The greater area installed, the larger is the capacity and thus also the CO2 savings. The share of total steam demand covered by solar is directly proportional to the demand in relation to the installed solar capacity. The fish industry, having the lowest steam demand in relation to the roof area, is found to be able to save the largest relative proportion of CO2 emissions. Different scenarios are presented, modifying the fuel cost and fuel type for the PTC-system’s boiler, adjusting the steam cost from the centralized suppliers and using two different solar fractions of 35% and 50%. The CO2 savings depends on what fuel is being used and the solar fraction. Larger CO2 reductions are possible with a gas fired boiler compared to a coal fired one. But using a coal fired boiler makes it more economically profitable, matching the low coal price used for the centralized supplier. The scenario with most CO2 reductions is attained when using a high solar fraction of 50% and a natural gas fired boiler. The annual CO2 savings is then ranging from 15 tons per year for the company having the lowest steam capacity, up to 2090 tons/year for the company with one of the highest. Another significant factor is the companies’ seasonal activity. For the company having the least amount of active days per year (84 out of 365 days), the PTC-system is unprofitable whichever scenario. However, fuel costs for the boiler is found to be one of the most significant factors for the outcome determining if the investigated PTC-system is profitable or not. For all of the companies, there was only one that could provide all its steam demand with the PTC-system. This indicates that other energy sources need to be integrated to provide the steam demand of the enterprises with a renewable energy system. / Att omvandla industrins energisystem med förnyelsebara energikällor är väsentligt för att bromsa klimatförändringarna. Det är inget undantag för Kina, som nuvarande har de största absoluta nivåerna av utsläpp av växthusgaser i världen. Industrin står för ca två tredjedelar av den nationella energiförbrukningen och kol är landets största energikälla. Integrerandet av andra alternativ såsom solenergi kan dock hjälpa till i landets energiomvandling. Denna rapport syftar till att presentera en tekno-ekonomisk analys av en decentraliserad solfångare och ge indikation på lönsamhet samt i vilken grad tekniken kan förse behovet av ånga för två industrier, textil och fiske, i Zhejiang provinsen i östra Kina. Den solfångarteknik som används är ett system med Parabolic trough collectors (PTCs) med integrerad gaseldad ångpanna. Systemet jämförs med kraftvärmeverk som drivs med kol. De analyserade faktorerna är takytan, solar fraction, solinstrålning, kostnad för ånga samt ångpannans bränslekostnader. Besparingarna för CO2-utsläpp beror på den potentiella installationsytan. Ju större installationsyta, desto högre kapacitet och därmed högre CO2-besparingar. Andelen av behovet ånga som kan förses med solfångare är i direkt proportion till takytan och det totala behovet. Fiskeindustrin, som har lägre ångbehov i relation till takyta, visar sig kunna spara den största relativa mängden CO2-utsläpp. Olika scenarier presenteras, där bränslekostnaden och typ av bränsle för PTC-systemets ångpanna modifieras, kostnaden för ånga från de centraliserade leverantörerna justeras och solar fraction ändras mellan 35% och 50%. Besparingarna i CO2-utsläpp beror på vilket bränsle som används samt solar fraction. Större CO2-reduktion är möjlig med en gaseldad panna jämfört med en koleldad. Dock är en koleldad panna lönsammare när den matchar det låga priset på kol som används för de centraliserade leverantörerna. Scenariot med de största CO2-besparingarna uppnås med en hög solar fraction på 50% och en naturgaseldad panna. De årliga CO2-besparingarna varierar från 15 ton per år för det företag som har den lägsta ångkapacitet, upp till 2090 ton per år för ett företag med en av den högsta kapaciteten ånga. En annan viktig faktor är företagens aktivitet per år. Företaget som har minst aktiva dagar per år (84 av 365 dagar), är ej lönsamt i något av de testade scenarierna. Bränslekostnaderna för pannan har emellertid visat sig vara en av de viktigaste faktorerna för resultatet som avgör om det undersökta PTC-systemet är lönsamt eller inte. Bland alla företagen fanns det bara ett som kunde förse hela sitt ångbehov, med PTC-systemet. Detta indikerar att andra energikällor måste införas för att förse företagens ångbehov med ett förnybart energisystem.
94

LowEx-Fernwärme: Vergleichende Bewertung von Maßnahmen für eine effiziente, multifunktionale Fernwärmeversorgung

Robbi, Steffen 16 September 2013 (has links)
Vor dem Hintergrund zunehmender Wärmedämmmaßnahmen im Wohnungsbau, das heißt sinkender Heizlasten, und gleichzeitigem Bestreben nach Netzausbau und –verdichtung steht die Fernwärmeversorgung neuen Problemstellungen gegenüber. Es gilt Lösungsansätze für das Spannungsfeld niedriger Liniendichten, steigender Brennstoffpreise und der Forderung nach erneuerbaren Energien in der Wärmeversorgung zu entwickeln. Die vorliegende Arbeit untersucht in einer vergleichenden Simulationsstudie diverse Fahrweisen der Fernwärmeversorgung auf unterschiedlichen Temperaturniveaus. Befindet sich die Fernwärmevorlauftemperatur unter der aus Gründen des Legionellenschutzes notwendigen Temperatur der Trinkwassererwärmung, erfolgt eine dezentrale Nacherwärmung. Diese geschieht innerhalb der sogenannten LowEx-Fahrweise mittels elektrischen Heizstabs oder einem Wärmepumpen-Speicherladesystem mit Wärmequelle Fernwärme. Als Referenzsysteme finden die als Konventionelle-Fahrweise mit Speicherladesystem und die als Niedertemperatur-Fahrweise mit Wohnungsanschlussstation im Durchflussprinzip bezeichneten Betriebsweisen Anwendung. Neben der Senkung der Netzwärmeverluste und ggf. einer Steigerung der Erzeugungswirkungsgrade ermöglicht die LowEx-Fahrweise die dezentrale Einspeisung von Abwärme oder erneuerbaren Energien bei effizientem Betrieb der Energiebereitstellungsanlagen. Das Fernwärmenetz dient damit der gekoppelten Wärmeversorgung und auch Wärmeentsorgung. Beispielhaft wird die Abwärmeeinspeisung von Klimakälteprozessen mit sowohl Kompressionskälteanlagen als auch Absorptionskältenlagen untersucht. Anhand Solarthermie wird das Für und Wider der Einspeisung erneuerbarer Energien hinsichtlich der Senkung des Primärenergiebedarfs und der Verdrängung von Kraft-Wärme-Kopplungsanlagen diskutiert. Die Analysen erfolgen mit Hilfe modifizierter und neu entwickelter Modelle in der Simulationsumgebung TRNSYS-TUD.
95

Control of carbon dioxide capture from biomass CHP plants : Designing a suitable control system to realize the flexible operation of the CO2 capture system

Rout, Tanmmay January 2023 (has links)
This degree project studies the integration of carbon capture system into biomass fired combined heat and power (bio-CHP) plants. The key disturbances from bio-CHP plants include flue gas flow rate, carbon dioxide (CO2) concentration and available heat for the reboiler because the use of versatile biomass and the dynamic operation of CHP plants results in large fluctuations in the properties of flue gas and the heat input for CO2 capture. To clearly understand the impacts of these disturbances on the performance of CO2 capture, a dynamic CO2 capture model is developed in Aspen Plus Dynamics by using monoethanolamine (MEA) based chemical absorption. Proportional-Integral (PI) feedback controllers are then implemented to further study and compare the performance of the CO2 capture process under different control strategies, the performance with general control settings and fine-tuned controllers are obtained and compared, including both the control performance and system performance. The control performance includes the maximum deviation and settling time, which could reflect only the performance of the controllers.  The system performance includes Captured CO2, reboiler duty and Energy penalty per unit CO2 captured, which could reflect CO2 capture system performance. An equilibrium stage steady state model is first developed for the key components in the CO2 capture plant in Aspen Plus, consisting of the absorber, the stripper, and lean-rich heat exchanger. By sizing the components and employing the pressure driven mode, the steady state model is enabled to be a dynamic model. The disturbances about flue gas and reboiler heat are taken from a real bio-CHP plant in Sweden. Considering the higher flue gas flowrate, the model has been scaled up to meet the requirement of this bio-CHP plant. The addition of controllers are done for the flexible operation of the CO2 capture system and the controlled variables considered in this study are the percentage of CO2 absorbed in the absorber column, reboiler temperature and rich solvent flow in the stripper column. The results show the effects of fluctuations in the key influencing factors on the control performance and the system performance . The fine-tuned controller implemented system showcases better performance when the quantity of CO2 captured is compared with that of the system in the absence of controllers, where a 1.1% increase in the amount of captured CO2 is observed when the flue gas flow rate is increased by 30%. The system also maintains a 1.8% higher capture rate when controllers are implemented. This showcases better system performance when controllers are implemented in the system. To further analyse the effects of control strategies two different control strategies are compared where controllers with general settings are compared to the controllers which are fine-tuning achieved by implementing tuning parameters which were obtained through Internal Model control (IMC) based on the system requirements. The fine tuning of the controllers results in improved system performance where the amount of captured CO2 increases by 1.4% when the reboiler duty is increased by 30% and a 1.7% decrease in the energy penalty per unit CO2 captured. Additionally, the results show that the settling time and maximum deviation are different for the two controllers where the controller which underwent fine tuning maintained the steady set point whereas the controller with general controller tuning showcases deviation before it attained stability. Therefore, the fine-tuned controller is more efficient to enable the flexible operation of CO2 capture when facing disturbance. It is studied that the tuning parameters implemented in the controllers affect the transient operation of the plant and improved the dynamic performance of the capture system. The tuned controllers offered more stability to the capture system while attaining their respective set points in a shorter time frame. It is also found that there exists a big difference between the system’s performance without controllers and that with finely tuned controllers. The difference in captured CO2 amount is approximately 26 ton/h when flue gas flow rate increases by 30%. The percentage difference is 1.1%, 7.7% and  5.9% for Captured CO2, reboiler duty and Energy penalty per unit CO2 captured respectively. In conclusion the control of the transient operation of the CO2 capture system needs the control system implemented and requires fine tuning parameters to achieve the desirable performance.
96

Auswirkungen der Kopplung von Strom- und Wärmemarkt auf die künftige Integration der erneuerbaren Energien und die CO2-Emissionen in Deutschland

Deac, Gerda 20 November 2020 (has links)
Die Dissertationsschrift untersucht die Interaktion zwischen Strom- und Wärmemarkt mit einem besonderen Fokus auf Wärmepumpen und Wärmenetzen. Vor dem Hintergrund des steigenden Ausbaus erneuerbarer Energien und der langfristigen Klimaziele stellt sich dabei die Frage der Wirkung, welche die Kopplung von Strom- und Wärmemarkt auf die Reduktion der CO2-Emissionen, die Energiesystemkosten und die Integration der erneuerbaren Energien hat. Zur Beantwortung der Forschungsfrage wird das lineare Optimierungsmodell Enertile um zwei Wärmemodule zur Berücksichtigung von Wärmepumpen und Wärmenetzen erweitert. Im Unterschied zu anderen Modellen wird in der Implementierung für diese Arbeit der Ausbau und der Einsatz der erneuerbaren Energien, der KWK und der weiteren fossilen Kraftwerkskapazitäten gleichzeitig optimiert, wodurch eine Analyse der Wechselwirkungen zwischen dem Ausbau erneuerbarer Energien und der Kopplung von Strom- und Wärmemarkt möglich ist. Die in dieser Arbeit vorgenommene modellgestützte Analyse zeigt die große Bedeutung der Interaktion zwischen Strom- und Wärmemarkt. Im Rahmen einer langfristigen Dekarbonisierung der Energieversorgung durch einen verstärkten Ausbau von erneuerbaren Energien ergeben sich sowohl Chancen als auch Herausforderungen für die Interaktion zwischen Strom- und Wärmemarkt. Die Modellierung der Wärmepumpen zeigt für den gesamten Zeitraum ab 2020 deutlich geringere spezifische CO2-Emissionen gegenüber der Wärmeerzeugung in modernen Gasbrennwertkesseln. Die Ergebnisse zeigen auch, dass bivalente Systeme – die kombinierte Nutzung verschiedener Wärmeerzeugungstechnologien wie beispielsweise KWK, Gasheizkessel und Elektroheizkessel – vor dem Hintergrund der Umstrukturierung des Stromsektors eine wichtige Rolle spielen. Langfristig stellt die flexible Wärmebereistellung durch elektrische Heizungstechnologien insbesondere bei hohen Anteilen erneuerbarer Energien eine kostengünstige und CO2-arme Alternative zur fossilen Wärmeerzeugung dar.:1 Einleitung 1 1.1 Ausgangslage 1 1.2 Problemstellung 3 1.3 Zielsetzung und Vorgehen 4 2 Rahmenbedingungen auf dem Strom- und Wärmemarkt in Deutschland 7 2.1 Rahmenbedingungen auf dem Strommarkt 7 2.2 Rahmenbedingungen auf dem Wärmemarkt 12 2.3 Schlussfolgerungen für diese Arbeit 16 3 Modellierung der Interaktionen von Strom- und Wärmemarkt 17 3.1 Stand der Forschung und Anforderungen an das Modell 17 3.2 Modelle zur Untersuchung von Strom- und Wärmemarkt 18 3.3 Stromsystemoptimierung Enertile 21 3.3.1 Eingangsdaten und Ergebnisse 23 3.3.2 Problemformulierung 24 3.4 Modellerweiterung zur Integration des Wärmemarktes 26 3.4.1 Wärmepumpen 26 3.4.2 Wärmenetze 32 4 Unsicherheiten in Energiesystemmodellen 42 4.1 Unsicherheiten im Rahmen dieser Arbeit 42 4.2 Methoden zum Umgang mit Unsicherheiten in Energiesystemmodellen 43 4.3 Szenarienentwicklung und Sensitivitäten 47 5 Definition von Szenarien zur Analyse der Wechselwirkungen zwischen Strom- und Wärmemarkt 50 5.1 Szenarienübersicht 50 5.2 Zentrale Annahmen 51 5.3 Strommarkt 56 5.3.1 Erneuerbare Energien 56 5.3.2 Konventionelle Kraftwerke 57 5.3.3 Stromnachfrage 59 5.4 Wärmenetze 59 5.5 Wärmepumpen 63 5.6 Sensitivitäten 65 5.7 Kritische Reflexion der Annahmen 66 6 Modellgestützte Analyse der Wechselwirkungen zwischen Strom- und Wärmemarkt 68 6.1 Einfluss auf die CO2-Emissionen 69 6.1.1 Strommarkt 69 6.1.2 Wärmepumpen 72 6.1.3 Wärmenetze 77 6.2 Entwicklung des Kraftwerksparks und des Erzeugungsmixes 82 6.2.1 Strommarkt 82 6.2.2 Wärmepumpen 95 6.2.3 Wärmenetze 106 6.2.4 Integration erneuerbarer Energien auf dem Strommarkt 128 6.3 Änderung der Systemkosten durch die Kopplung von Strom- und Wärmemarkt 131 6.3.1 Kosten der Stromerzeugung 132 6.3.2 Kosten der Wärmeerzeugung in Wärmepumpen 134 6.3.3 Kosten der Wärmeerzeugung in Wärmenetze 136 6.4 Zusammenfassung der Szenarienanalyse 140 6.4.1 Einfluss der Kopplung von Strom- und Wärmemarkt bei ambitionierten Klimaschutz 140 6.4.2 Einfluss der Kopplung von Strom- und Wärmemarkt bei mäßigem Klimaschutz 141 7 Sensitivitäten 142 7.1 Stabile Brennstoffpreise 142 7.2 Potentiale von erneuerbaren Energien 145 7.3 Isolierte Effekte von Elektroheizkesseln und KWK 148 7.3.1 Keine KWK 148 7.3.2 Keine Elektroheizkessel 150 7.4 Hohe Flexibilität der Wärmepumpen 151 7.5 Zusammenfassung Sensitivitäten 152 8 Zusammenfassung 154 8.1 Motivation und Forschungsfrage 154 8.2 Methodisches Vorgehen 154 8.3 Ergebnisse 155 8.4 Schlussfolgerungen und kritische Reflektion 156 8.4.1 Szenarienanalyse 156 8.4.2 Methodik 157 8.4.3 Ausblick 159
97

Application of Modular Uncertainty Techniques to Engineering Systems

Long, William C 04 May 2018 (has links)
Uncertainty analysis is crucial to any thorough analysis of an engineering system. Traditional uncertainty analysis can be a tedious task involving numerous steps that can be error prone if conducted by hand. If conducted with the aid of a computer, these tasks can be computationally expensive. In either case, the process is quite rigid. If a parameter of the system is modified or the system configuration is changed, the entire uncertainty analysis process must be conducted again giving more opportunities for calculation errors or computation time. Modular uncertainty analysis provides a method to overcome all these obstacles of traditional uncertainty analysis. The modular technique is well suited for computation by a computer which makes the process somewhat automatic after the initial setup and computation errors are reduced. The modular technique implements matrix operations to conduct the analysis. This in turns makes the process more efficient than traditional methods because computers are well suited for matrix operations. Since the modular technique implements matrix operations, the method is adaptable to system parameter or configuration modifications. The modular technique also lends itself to quickly calculating other uncertainty analysis parameters such as the uncertainty magnification factor, and the uncertainty percent contribution. This dissertation will focuson the modular technique, the extension of the technique in the form the uncertainty magnification factor and uncertainty percent contribution, and the application of the modular technique to different type of energy systems. The modular technique is applied to an internal combustion engine with a bottoming organic Rankine cycle system, a combined heat and power system, and a heating, ventilation, and air conditioning system. The results show that the modular technique is well suited to evaluate complex engineering systems. The modular technique is also shown to perform well when system parameters or configurations are modified.
98

A Cooling, Heating, And Power For Buildings (Chp-B) Instructional Module

Hardy, John David 10 May 2003 (has links)
An emerging category of energy systems, consisting of power generation equipment coupled with thermally-activated components, has evolved as Cooling, Heating, and Power (CHP). The application of CHP systems to buildings has developed into a new paradigm ? Cooling, Heating, and Power for Buildings (CHP-B). This instructional module has been developed to introduce undergraduate engineering students to CHP-B. In the typical ME curriculum, a number of courses could contain topics related to CHP. Thermodynamics, heat transfer, thermal systems design, heat and power, alternate energy systems, and HVAC courses are appropriate for CHP topics. However, the types of material needed for this mix of courses vary. In thermodynamics, basic problems involving a CHP flavor are needed, but in an alternate energy systems course much more CHP detail and content would be required. This series of lectures on CHP-B contains both a stand-alone CHP treatment and a compilation of problems/exercises.
99

Carbon Negative Heat and Power with Biochar Production : An Economic Analysis of a Combined Pyrolysis and CHP plant / Kolnegativ kraft och värme med biokolsproduktion : En ekonomisk analys av ett kombinerat pyrolys- och kraftvärmeverk

Bydén, William, Fridlund, David January 2020 (has links)
On the fourth of November 2016, The Paris Agreement entered into force, stating that nations worldwide should pursue efforts to limit the global temperature increase to 1,5 °C. Since then, the Intergovernmental Panel on Climate Change has specified that carbon dioxide removal, such as biochar sequestration, is necessary to achieve this goal. Biochar is a solid and porous material, rich in carbon, produced when biomass undergoes a process called pyrolysis and can, if buried in soil, sequester carbon for hundreds or even thousands of years while at the same time acting as a soil amendment. When biomass is pyrolyzed to produce biochar, a pyrolysis gas is also produced, which can be used to generate both heat and electricity. This thesis investigates if constructing and operating a plant, called a combined pyrolysis and CHP plant, which combines biochar production with heat and electricity generation, could be economically feasible and thus be an effective method for carbon dioxide removal. The findings show that constructing and operating a combined pyrolysis and CHP plant can be economically feasible. However, the economic feasibility is greatly affected by the price of biochar as a soil amendment product. The biochar market is also an undeveloped market, making price estimates of biochar far from accurate. Another factor that could significantly affect the economic feasibility of the plant is the fraction of carbon in biochar, which can be accounted for as sequestered. A higher fraction means that significantly more governmental support can be given to provide financing of the plant as well as potential revenue from carbon credits could increase. The capital cost of constructing the plant is also a factor with high uncertainty, which has a substantial effect on the economic feasibility. From this thesis, it is concluded that more research regarding the biochar market, as well as the capital costs of constructing the plant, is needed. More research could further ascertain whether or not the plant could be economically feasible and thus, an effective method for carbon dioxide removal. / Den fjärde november 2016 trädde Parisavtalet i kraft vilket uppgav att länder över hela världen ska sträva efter att begränsa den globala temperaturökningen till 1,5 grader Celsius. I enlighet med detta mål har FN:s mellanstatliga klimatpanel, IPCC, specificerat att koldioxidavlägsnande åtgärder, såsom kolinlagring genom produktion av biokol, är nödvändigt. Biokol är ett fast och poröst material, rikt på kol, som produceras när biomassa genomgår en process som kallas pyrolys. Om biokol blandas ner i jord kan det binda kol i hundratals eller tusentals år samtidigt som det fungerar som jordförbättrare. När biomassa pyrolyseras produceras också en pyrolysgas som kan användas för att generera värme och elektricitet. Det här examensarbetet undersöker om det kan vara ekonomiskt genomförbart att bygga och driva en anläggning, benämnd en kombinerad pyrolys- och kraftvärmeanläggning, som kombinerar biokolsproduktion med värme- och elproduktion för att avlägsna koldioxid från atmosfären. Resultaten från arbetet visar att det kan vara ekonomiskt genomförbart att bygga och driva en kombinerad pyrolys- och kraftvärmeanläggning. Den ekonomiska genomförbarheten påverkas dock i hög grad av priset på biokol som jordförbättringsprodukt. Marknaden för biokol är dessutom outvecklad vilket gör att priset för biokol osäkert. En annan faktor som i hög grad skulle kunna påverka den ekonomiska genomförbarheten för anläggningen är andelen kol i biokol som kan anses vara lagrad. En högre andel innebär att betydligt mer statligt stöd kan ges för att finansiera anläggningen samt att potentiella intäkter från kolkrediter kan öka. Kapitalkostnaderna för att bygga anläggningen är också en faktor med hög osäkerhet som har stor effekt på den ekonomiska genomförbarheten. Från detta examensarbete dras slutsatsen att mer forskning kring biokolsmarknaden samt kring kapitalkostnaderna för att bygga anläggningen behövs. Detta behövs för att ytterligare fastställa den ekonomiska genomförbarheten hos en sådan anläggning för att avlägsna koldioxid från atmosfären.
100

Analysis of the Feasibility of Integrating Pellet Production to an Existing Combined Heat and Power Plant: A Case Study of Bristaverket : A Techno-Economic Analysis and an Investigation of Possibilities for Organizational Learning / Analys av genomförbarheten att integrera pelletsproduktion med ett existerande kraftvärmeverk: En fallstudie av Bristaverket  : En teknoekonomisk analys och en undersökning av möjligheter till organisatoriskt lärande

Banck, Filippa, Westlin, Albin January 2024 (has links)
This study explored the feasibility of integrating pellet production to the combined heat and power plant Bristaverket, owned by the energy company Stockholm Exergi, with the aim of achieving a more energy and resource efficient process. The study was divided into three parts: development of a technical process, evaluation of techno-economic performance, and examination of organizational learning opportunities. A limitation of the study was to only consider the process at Bristaverket. The technical process was developed following a general modeling design process, utilizing MATLAB as software. Economic performance was assessed through investment and sensitivity analysis. Organizational learning opportunities were identified through interviews and thematic analysis using the 4I-framework. The proposed technical process involved transferring heat from Bristaverket to a 4 MW water-heated belt dryer. The annual pellet production amounted to 50.4 kilotons with 85% plant operation, and the specific energy consumption was 717 kWh/tpellet. The pellets achieved the classification I3 for industrial use and the specific production cost was 2,218 SEK/tpellet. The investment analysis was executed for three scenarios: a future scenario, a 2020 scenario and a 2023 scenario. The future scenario yielded a net present value (NPV) of 270 MSEK, an investment return rate (IRR) of 74%, and a payback time (PBT) of 1.4 years. For the 2020 scenario and 2023 scenario, the NPV was -1 MSEK and 88 MSEK, the IRR was 8% and 32%, and the PBT was 9.5 years and 3.3 years respectively. The investment was sensitive to changes in operational costs, foremost changes in pellet and wood chip prices. The study's techno-economic findings could contribute to organizational learning at Stockholm Exergi during meetings, through questions, at the final presentation, and through conversations between colleagues. Suggestions for enhancing organizational learning included establishing routines for knowledge sharing and discussions during and after thesis projects. / Denna studie utforskade möjligheten att integrera pelletsproduktion vid kraftvärmeverket Bristaverket, som ägs av energiföretaget Stockholm Exergi, med syfte att uppnå en mer energi- och resurseffektiv process. Studien delades in i tre delar: utveckling av en teknisk process, utvärdering av teknoekonomiskt resultat och undersökning av möjligheter till organisatoriskt lärande. En avgränsning som gjordes i studien var att bara undersöka processen i Bristaverket. Den tekniska processen utvecklades genom att följa en allmän modelleringsdesignprocess med MATLAB som programvara. Det ekonomiska resultatet utvärderades genom investerings- och känslighetsanalys. Möjligheter till organisatoriskt lärande identifierades genom intervjuer och tematisk analys med hjälp av 4Iramverket. Den föreslagna tekniska processen innebar överföring av värme från Bristaverket till en 4 MW vattenuppvärmd bandtork. Den årliga pelletsproduktionen uppgick till 50,4 kiloton med 85% drifttid och den specifika energiförbrukning var 717 kWh/tpellet. Pelletsen klassificerades som I3 för industriellt bruk och den specifika produktionskostnaden var 2 218 SEK/tpellet. Investeringsanalysen gjordes för tre scenarios: ett framtidsscenario, ett 2020-scenario och ett 2023-scenario. Framtidsscenariot gav ett nettonuvärde på 270 MSEK, en internränta på 74 % och en återbetalningstid på 1,4 år. För 2020- och 2023-scenariot var nettonuvärdet -1 respektive 88 MSEK, internräntan 8 respektive 32 % och återbetalningstiden 9,5 respektive 3,3 år. Investeringen var känslig mot förändringar i driftkostnader, framför allt i form av pellets- och flispriser. Studiens teknoekonomiska resultat skulle kunna bidra till organisatoriskt lärande på Stockholm Exergi genom möten, frågor, vid slutpresentationen och genom samtal mellan kollegor. Förslag för att förbättra möjligheterna till organisatoriskt lärande inkluderade att etablera rutiner för kunskapsdelning och diskussioner under och efter examensprojekt.

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