Climate change is an important topic of today's discussion where scientists have determined that a large proportion of the increasing global temperatures is a product of the increasing greenhouse gases in the atmosphere. Globally it is expected that the share of renewable power generation is set to increase with 50 % between 2019 and 2024. Together with cost reductions and advancements in renewable energy technologies this opens up an opportunity for companies and market actors to reevaluate their power generation systems. By utilising a polygeneration system an energy system is able to combine multiple energy sources to produce several energy services in an efficient, cost effective and sustainable way. This thesis analyses the possibilities of implementing alternative power generation systems for a unit in the Swedish Armed Forces. In close conjunction with the Swedish Armed Forces works The Swedish Defence Material Administration with the primary assignment to procure, develop and deliver equipment and services to the Swedish defence. In this thesis, a Ground Based Air Defence Operations Center is used as a case study which utilises diesel gensets for power generation. The energy system of the unit is analysed as well as the power, heat and cooling demands. Different scenarios based on current and future developments in energy technology are modelled in the microgrid software Homer Pro. The system model 1 for the scenarios BAU, AF1 and AF2 requires no modification of the gensets in the current power generation system. Instead alternative fuel types are modelled where a biodiesel B20 blend is used for AF1 and 1 hydrogenated vegetable oil is used in the AF2 scenario. In the scenarios using the system model 2, FS1 is utilising the current genset upgraded with a heat recovery system running on hydrogenated vegetable oil. The FS2 scenario proposes a microturbine with a capacity of 30 kW as an alternative to the current genset. In the FIFS scenario a PEM fuel cell is modelled, also having a capacity of 30 kW. All of the system model 2 configurations included a battery system, a membrane distiller for water purification and a thermal storage tank as additional units. The main results from the thesis show that all scenarios except for FS2 reduce the annual emissions from the unit. However, this brings a higher net present value for the systems as well as a higher yearly operation cost. The results indicate that the FS1 scenario is able to decrease the CO2 emissions with almost 50 % with adjustments to the current gensets as well as providing the unit with excess heat for water purification and storage in the thermal tank. / Klimatförändringen är ett viktigt ämne idag där forskare har fastställt att en stor andel av ökningen av medeltemperaturen beror på ökade växthusgaser i atmosfären. Globalt förväntas kraftgenerering från förnybara källor att öka med 50 % mellan åren 2019 till 2024. Detta i samband med kostnadsminskningar och framsteg inom förnybara energiteknologier leder till en möjlighet för företag och aktörer att omvärdera sina energisystem. Genom att använda ett polygenereringssystem kan ett energisystem kombinera flera energikällor för att producera fler energitjänster på ett hållbart och kostnadseffektivt sätt. Detta examensarbete undersöker möjligheten att implementera alternativa kraftgenereringssystem för en enhet i Försvarsmakten. I ett nära samarbete med Försvarsmakten arbetar Försvarets Materielverk med det primära uppdraget att upphandla, utveckla och leverera materiel och tjänster till det svenska försvaret. I detta arbete har en luftvärnscentral som nyttjar dieselgeneratorer för kraftproduktion använts som en fallstudie. Enhetens energisystem har analyserats och därtill även el-, värme- och kylbehovet för denna enhet. Olika scenarier baserat på nuvarande och framtida utveckling inom energiteknik har modellerats i microgridprogrammet Homer Pro. För system modellerna 1 i scenarierna BAU, AF1 och AF2 görs inga modifieringar av befintliga system utöver bränsletyp. Scenario AF1 använder en biodieselblandning B20 och i AF2 drivs systemet med vätgasbehandlad växtolja. För modellerna som använder sig utav system modellerna 2 är FS1 ett scenario baserat på en uppgradering av nuvarande kraftenhet genom en värmeåtervinningsenhet. FS2 föreslår en alternativ kraftenhet i form av en mikroturbin med en kapacitet på 30 kW. En PEM-bränslecell är modellerad i scenario FIFS som även den har en kapacitet på 30 kW. Tillhörande komponenter till system modellerna 2 är ett batterisystem, en vattenreningsenhet och en varmvattentank. Resultaten visar att alla scenarier förutom FS2 minskar de årliga utsläppen från enheten. Detta på en bekostnad av en högre nuvärdeskostnad och en högre årlig kostnad för driften av systemen. Från simuleringen visar resultaten även att FS1 kan bidra till att minska utsläppen med nästan 50 % genom justeringar av nuvarande kraftenhet samtidigt som systemet levererar överskottsvärme för vattenrening och lagring i varmvattentanken.

In recent times the problems regarding global warming and climate change have become increasingly relevant in our society. Public attention is growing due to seemingly larger and more severe natural disasters each year and the search for solutions to these problems is greater than ever. Humanity is facing a lot of environmental challenges, but one could argue that the increasing rate of greenhouse gas emissions related to energy production and use is the main focus. This study focuses on how electricity generating and storage technologies can be installed for different types of buildings and businesses to maximize economic benefits and at the same time reduce dependency on grid bought electricity. The buildings in the analysis will have prior solar PV systems installed ranging from 35 kW to 254.8 kW in capacity. Three different buildings within this interval have been chosen and have the solar PV capacity of 35.84 kW, 143.36 kW and 254.8 kW. These buildings have been chosen to get three different load profiles that are as different as possible, given the available data. The study concludes that only using solar PV is the financially most profitable system configuration for all three buildings, rated by maximum IRR. Both wind power and batteries have a negative impact on IRR for all buildings. The building with the least changes in day-to-day peak demand benefited the most from solar PV. Wind power affects the demand in a similar way as solar PV, however batteries added more value to a building with a less consistent load curve. / På senare tid har problemen med global uppvärmning och klimatförändringar blivit alltmer relevanta i vårt samhälle. Allmänhetens uppmärksamhet växer på grund av till synes större och allvarligare naturkatastrofer varje år och sökandet efter lösningar på dessa problem är större än någonsin. Mänskligheten står inför många miljömässiga utmaningar, men det går att hävda att den ökande andelen växthusgasutsläpp relaterade till energiproduktion och användning är huvudfokus. Denna studie fokuserar på hur elproduktionens- och lagringsteknologier kan installeras för olika typer av byggnader och företag för att maximera ekonomiska fördelar och samtidigt minska beroendet av köpt el från elnätet. Byggnaderna i analysen har tidigare installerade solcellsanläggningar som sträcker sig från 35 kW till 254.8 kW. Tre olika byggnader inom detta intervall har valts och för dessa var solenergikapaciteten 35.84 kW, 143.36 kW och 254.8 kW. Dessa byggnader har valts för att få tre olika elförbrukningsprofiler som är så olika som möjligt med tanke på den tillgängliga datan. Studien drar slutsatsen att användningen av endast PV är den ekonomiskt est lönsamma systemkonfigurationen för alla tre byggnader, rankad efter maximal IRR. Både vindkraft och batterier påverkar IRR negativt för alla byggnaderna. Byggnaden med minst förändringar i det dagliga toppbehovet gynnades mest av solceller. Vindkraft påverkar elbehovet på liknande sätt som PV, men batterierna däremot gav mer värde till en byggnad med en förbrukningsprofil som var mindre konsekvent.

Today’s biomass-fired combined heat and power (CHP) plants have surplus heat production capacity during warmer times of the year. In order to allow them to increase their electricity production, it is essential to find a use for the surplus heat. Additionally, the transport sector is struggling with high fuel prices and the contribution of CO2 emissions to global warming. A promising way of reducing the negative effects caused by combustion of fossil fuels in the transport sector is to mix ethanol with gasoline, or to use pure ethanol in modified engines. Ethanol is produced by fermentation at low temperatures and the production process could be integrated with CHP plants. The first generation of ethanol production as fuel has recently been criticized for competing with food crops and for its production chain being a larger polluter than was first thought. The second generation of ethanol production from lignocellulosic materials offers very promising results, but this process has several steps that are energy demanding. This thesis presents the findings of research on the configuration of a CHP plant with an integrated second generation ethanol production process. It also presents the operational economics and optimal locations for such plants in Sweden. Two case studies were performed to compare different feedstocks for ethanol production. The results show that when electricity prices are high, CHP plants benefit from heat consumption. Even with low yields in an ethanol production process, the integrated plant can be profitable. The plant must be located where there is sufficient heat demand. A cellulosic ethanol production process can work as a heat sink with profitable outcomes even with the current state of development of cellulosic ethanol technology.

abstract: Just for a moment! Imagine you live in Arizona without air-conditioning systems! Air-conditioning and refrigeration systems are one of the most crucial systems in anyone’s house and car these days. Energy resources are becoming more scarce and expensive. Most of the currently used refrigerants have brought an international concern about global warming. The search for more efficient cooling/refrigeration systems with environmental friendly refrigerants has become more and more important so as to reduce greenhouse gas emissions and ensure sustainable and affordable energy systems. The most widely used air-conditioning and refrigeration system, based on the vapor compression cycle, is driven by converting electricity into mechanical work which is a high quality type of energy. However, these systems can instead be possibly driven by heat, be made solid-state (i.e., thermoelectric cooling), consist entirely of a gaseous working fluid (i.e., reverse Brayton cycle), etc. This research explores several thermally driven cooling systems in order to understand and further overcome some of the major drawbacks associated with their performance as well as their high capital costs. In the second chapter, we investigate the opportunities for integrating single- and double-stage ammonia-water (NH3–H2O) absorption refrigeration systems with multi-effect distillation (MED) via cascade of rejected heat for large-scale plants. Similarly, in the third chapter, we explore a new polygeneration cooling-power cycle’s performance based on Rankine, reverse Brayton, ejector, and liquid desiccant cycles to produce power, cooling, and possibly fresh water for various configurations. Different configurations are considered from an energy perspective and are compared to stand-alone systems. In the last chapter, a new simple, inexpensive, scalable, environmentally friendly cooling system based on an adsorption heat pump system and evacuated tube solar collector is experimentally and theoretically studied. The system is destined as a small-scale system to harness solar radiation to provide a cooling effect directly in one system. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2018

The primary water sources of twenty million people in Bangladesh are contaminated with arsenic; almost sixty percent of population does not have access to electricity, and close to ninety percent of the population cooks with solid fuels. These statistics have severe health and development implications for Bangladesh. Polygeneration technology is being developed that can address all of these issues with a single system, by utilizing the exhaust heat from a biogas electricity generator to remove arsenic from water via membrane distillation and using excess biogas as a cooking fuel. History is full of stories of investment in developing countries gone horribly wrong. Thorough market research and analysis can help prevent that in the future. This thesis demonstrates the process of determining beneficial components of business models for the deployment of polygeneration technology in Bangladesh. This involves understanding the existing business models used for providing rural services in Bangladesh and assessing which of these models would be more sustainable for biogas based polygeneration systems within the socio-economic and institutional context of rural Bangladesh. This is achieved through the development of a set of sustainability indicators and an interview questionnaire for providers of rural services in Bangladesh, which was applied during a field study in early 2013. The sustainability indicator scores were calculated and analyzed in the context of strategic management tools, such as the Business Model Canvas. The combination of the quantitative and qualitative aspects of these case studies highlights crucial business model elements. Based on the results of the sustainability indicators for the field sites included in the study, community and cooperative business models provide a sustainable structure for the multiple products and inputs inherent in a polygeneration system. They have the ability to reach a wider customer base and are not focused on maximizing their profit, but still make reasonable economic choices.

While the quest of the human civilization continues towards a more sustainable energy resource, current energy conversion technologies need to be improved such that the rate of environmental impact that has occurred due to the rapid industrialization since the 20th century is mitigated. This search has motivated research into new energy conversion technologies that aim to reduce the environmental impact by either improving the efficiencies of existing technologies, developing new technologies with zero emissions or by improving reliability and reducing the cost of renewable energy. Process intensification through process integration is one of the areas of active research that improves the system efficiency by exploiting the synergies that exist between different processes. This thesis considers the design and operational feasibility of heat integrating two conventional industrial processes – gasification and steam reforming of methane for application in polygeneration. To this end, complex mathematical models that describe the integrated system are developed to study different design prospects and to determine if the device can be safely operated in a plant producing electricity, liquid fuels and hydrogen. The designs proposed in this thesis show that significant methane conversion comparable to industrial reformers can be achieved while providing the required cooling duty to the gasifier. The proposed integrated system produces hydrogen rich reformer synthesis gas (hydrogen and carbon monoxide) that can be blended with the hydrogen lean coal synthesis gas providing flexibility to change the molar H2/CO ratio necessary for different downstream processes in a polygeneration plant. Moreover, the results show that the integration helps improve plant carbon efficiency and reduce CO2 emissions. The major contribution of this thesis is the development of designs based on representative mathematical models that are safe to operate for producing several chemicals in polygeneration plants. / Dissertation / Doctor of Philosophy (PhD)

Due to the advancement of global warming internationally, increasing emphasis is being placed on the environmental accountability of everyone from countries to processes. This study presents novel research on the environmental impacts and economic trade-offs for a processes co-producing electricity, methanol, dimethyl ether (DME) and Fischer Tropsch (FT) fuels from different feedstock ratios of biomass, natural gas, and nuclear hydrogen generated through a CuCl cycle are analyzed for operation in Canada to produce transportation fuels. This study also considers the use of carbon capture and sequestration (CCS), the location of the plant in either Ontario and Alberta, and the input ratio of the feedstocks. This combination of carbonless heat and a “carbon neutral” biomass feedstock would contribute to the net reduction of greenhouse gas (GHG) emissions. In Part I of this work, the model for this BGNTL process was developed. This work expands on the model and evaluates the economics and environmental impacts this plant would have in both Ontario and Alberta based on their local costs, resource availability, and current electricity grid contributions. The analysis investigates the effectiveness of the emission reduction of the products and processes when compared to their cost. It is shown that an increase in the ratio of biomass to natural gas in feedstock, the use of a solid oxide fuel cell (SOFC), and the production of additional electricity while reducing the emissions of the process, increases the cost of CO2e avoided. The results show that the BGNTL concept can be an economically attractive way of reducing net transportation sector GHG emissions in both Ontario and Alberta in meaningful quantities. Optimal cases for both biofuel and FT fuel production contain a single output fuel production process, produce fuels over electricity where possible, and use a gas turbine (GT) for the electricity production that occurs. / Thesis / Master of Engineering (MEngr) / This paper examines a system producing a combination of transportation fuels including diesel, gasoline, methanol (MeOH), dimethyl ether (DME) and electricity from biomass, natural gas and hydrogen. The design of the system units used in the process was done in a previous study, this work expands on the design looking specifically at locating the plant in Ontario and Alberta for their raw resources, electricity grids, and current production methods of fuel. Variations of the plant are compared to each other and current fuel and electricity production with an aim of reducing the cost and emissions created while producing and using the fuels. It is found that increasing the amount of biomass used significantly reduces the emissions but does not create a competitive process due to how expensive it is. Results show that this type of system can decrease transportation sector emissions with a similar additional cost as other current alternatives.

I ett modernt samhälle är elektricitet en nyckelkomponent för industrins, individens och samhällets utveckling. Naturkatastrofområden där elektriciteten slagits ut står inför stora prövningar för att kunna få samhällsviktiga funktioner att fungera igen. Med hjälp av den mobila miljövänlig energienhet Emergency Energy Module (EEM) kan elbehovet lindras. Detta examensarbetes mål var att ta fram en elsystemsbeskrivning för den kommande Export container (EXC), samt ta fram ett korrekt elschema för den befintliga EEM. Elsystemsbeskrivningen måste ta hänsyn till EXC:s kravspecifikation samt innehålla Bills of Material (BoM) och elschema. Problematiken ligger bl.a. i att få flera olika energikällor (sol, vind och biomassa förgasare) att fungera tillsammans i ett elsystem där likspänning, växelspänning, trefas och enfas blandas. Stor vikt ligger också vid att få ett flexibelt elsystem som relativt lätt kan förändras efter olika kunders behov. Genomförandet av detta examensarbete utfördes inledningsvis med en faktainsamligs-fas. Detta efterföljdes av en genomgång och analys av EEM:s elsystem vilket resulterade i ett elschema och en manual. Svagheter i EEM:s elsystem ansågs vara avsaknaden av överspänningsskydd och jordfelsbrytare, mätpunkt 5 var felplacerad, mätutrustningen borde av säkerhetsskäl vara fastmonterade och 1-fas generator borde användas i biomassaförgasaren för att avlägsna snedbelastningsproblem. Den befintliga Power routern, vars uppgift är att kontrollera energiflöde i systemet, ansågs begränsad eftersom den endast kunde ta emot en AC-energikälla, endast hantera 1-fas samt hade en relativt låg max uteffekt på 5,5 kW. Med hjälp av analysens funna svagheter och med hänsyn till EXC:s kravspecifikation konstruerades sedan ett elsystem för EXC med tillhörande BoM, elschema, kravspecifikation avseende delsystem och förslag på kandidater som uppfyller dessa. Elsystemet rekommenderas byggas kring Power routern Quattro vilket ger stora möjligheter till flexibilitet i form av att kunna skala upp systemet om bl.a. mer effekt skulle önskas av kund, eller om det finns behov av 3-fas system. En mängd olika programmeringsinställningar kan då göras vilket underlättar uppbyggnaden av specifika elsystem efter varierande kunders behov. / In a modern society electricity is a key component for the development of the individual, industry, and society. Natural disaster areas where the electricity has been knocked out face great trials in order to get vital public functions working again. With the help of the mobile eco-friendly energy device Emergency Energy Module (EEM) electricity needs can be eased. The goal of thesis was to produce an electrical power system description for the upcoming Export container (EXC), and to generate a correct circuit diagram for the existing Emergency energy module (EEM). The electric power description must take into account EXC's specifications and include Bills of Material (BoM) and circuit diagram. The problems lies in getting the various sources of energy (solar, wind and biomass gasifier) to work together in a power system where DC, AC, three-phase and single-phase are mixed. Great emphasis is also given to obtain a flexible electricity systems that can be relatively easily changed for different customer needs. The making of this thesis was carried out initially with a gathering facts phase. This was followed by a review and analysis of the EEM's electrical system which resulted in a circuit diagram and a manual. Weaknesses in EEM's electrical system was considered to be the lack of overvoltage protection and residual current device, measuring point 5 was misplaced, measuring equipment should for safety reasons be firmly attached and 1-phase generator should be used in biomass gasifier to remove uneven load problems. The existing Power router, whose task is to control the energy flow in the system, was limited because it could only receive one AC power source, handle only one-phase and had a relatively low maximum output power of 5.5 kW. Whit the help of the analysis improvement suggestions above and with EXC's specification taking into account was then an electric power system for EXC constructed. with associated BoM, circuit diagram, specifications for subsystems and proposals for candidates that meet these. The electrical system is recommended to be built around the Power router Quattro which provides great opportunities for flexibility in terms of being able to scale up the system if such more power would be desired by the customer, or if there is a need for 3-phase systems. A variety of programming settings can then be made which facilitates the construction of specific electrical systems for varying customer needs.

The optimal design and operation of an energy supply system is very important for the matching of the energy production and consumption especially in the residential-tertiary sector characterized by an energy demand with a high variability. The main objective of this thesis is to develop an optimisation environment for the preliminary design and analysis of polygeneration plants. The optimisation models are organized in different units represented by blocks that can be connected between each other to create the flowsheet of the polygeneration system. To characterize the energy demand in the residential and tertiary sector a graphic methodology has been developed to select typical energy demand days from a yearly energy demand profile. The environment developed has been applied to two case studies: a small scale polygeneration plant using a liquid desiccant system for air conditioning and a polygeneration plant connected to a district heating and cooling network.

Submitted by ADRIANA LOPEZ VARGAS (adrialovargas@gmail.com) on 2016-04-14T14:20:54Z No. of bitstreams: 1 Analise de oportunidades de poligeração para edificações e cidades - Adriana Lopez Vargas.pdf: 3896010 bytes, checksum: 3c34d108a2a908648717c9ac5860cd3d (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-18T16:55:10Z (GMT) No. of bitstreams: 1 vargas_al_me_guara.pdf: 3896010 bytes, checksum: 3c34d108a2a908648717c9ac5860cd3d (MD5) / Made available in DSpace on 2016-04-18T16:55:10Z (GMT). No. of bitstreams: 1 vargas_al_me_guara.pdf: 3896010 bytes, checksum: 3c34d108a2a908648717c9ac5860cd3d (MD5) Previous issue date: 2016-02-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A geração de energia distribuída em edificações e cidades tem sido proposta como uma importante alternativa para que os países ampliem a base tecnológica de suas matrizes energéticas. No caso do Brasil, a possibilidade da incorporação da geração distribuída em edificações apresenta amparo legal por meio de recentes regulamentações do setor elétrico e das normas de melhoria da eficiência energética de edificações. Por estas razões, novos empreendimentos imobiliários com visão de sustentabilidade ambiental, estão avaliando o uso da geração distribuída na etapa de planejamento. Nesta dissertação, foi analisada uma proposta para atender as necessidades energéticas de um hospital (vapor, água quente, resfriamento e eletricidade) considerando as informações de demanda, classificadas em oito dias típicos do ano, dois por cada estação do ano (outono, inverno, primavera e verão) sendo um dia de trabalho normal e outro de final de semana. A proposta consiste na otimização de uma superestrutura composta de diferentes tecnologias de geração e cogeração incluindo equipamentos solares, para assim obter a melhor configuração em termos econômicos. A superestrutura é flexível, ou seja, permite a venda ou compra de eletricidade e analisa três casos, verificando-se a viabilidade de gerar mais eletricidade. Finalmente são apresentados os resultados da configuração final obtida pela otimização. / Distributed generation in buildings and cities has been proposed as an important option for countries in order to include more technologies in their energy mixes. In Brazil, the possibility of including distributed generation in buildings has recent advances in energy policy and building energy efficiency standards. For these reasons, new construction projects of sustainable buildings include the assessment of distributed generation in the initial stages. In this work, we present an approach for attending energy needs (steam, hot water, cooling and electricity) of a hospital. The information about demand is classified in eight typical days, two for each season of the year (autumn, winter, spring and summer); a workday and a weekend day. The approach consists in the optimization of a superstructure containing different energy generation and cogeneration technologies like solar panels, for obtaining the best configuration in economic terms. The superstructure is flexible, this is, it allows buying or selling electricity. It also analyzes three cases, verifying the feasibility for generating more electricity. Finally, the results present the final configuration obtained from the optimization process.