Dissertations / Theses on the topic 'Exergy cost'

Natural gas liquefaction processes are energy and cost intensive. This thesis pursues the optimisation of propane precooled mixed refrigerant (C3MR) processes considering variations in upstream gas well conditions, in order to maximise gas well life. Four objective functions were selected for the design optimisation of the C3MR and dual mixed refrigerant (DMR) processes: 1) total shaft work (W), 2) total capital investment, 3) total annualised cost, and 4) total capital cost of both compressors and main cryogenic heat exchanger (MCHE). Optimisation results show that objective function 4 is more suitable than other objective functions for reducing both W and UA (MCHE design parameter). This leads to 15% reduction in specific power for C3MR and 27% for DMR, while achieving lower UA values relative to baseline. The operation optimisation of the C3MR process and its split propane version (C3MR-SP) was performed using four objective functions: 1) total shaft work, 2-3) two different exergy efficiency expressions, and 4) operating expenditure (OPEX). Objective function 3 results in the lowest specific shaft work 1469 MJ/tonne-LNG. For C3MR-SP, however, the lowest specific shaft work is found to be under objective function 1. A comparison of optimisation results across literature studies is impractical due to dissimilar process conditions, feed gas conditions, product quality, and equipment size. A sensitivity analysis highlights the effect of feed gas conditions on performance of the C3MR. For instance, as LNG production decreases from 3 MTPA to 2.4 MTPA over time, the specific OPEX increases from $128/tonne-LNG to $154/tonne-LNG. A subsequent study was conducted focusing on energy benefits of two configurations: integrating natural gas liquids (NGL) recovery unit with C3MR. An integrated NGL recovery within C3MR shows a 0.74% increase in energy consumption as methane concentration of the feed gas decreases, however a frontend NGL recovery unit only has a 0.18% decrease.

O hidrogênio molecular (H2) é um gás muito útil nas indústrias químicas e petroquímicas por conta de sua facilidade de reação com outros elementos químicos. Nas refinarias é o principal insumo no processo de remoção do enxofre de diversos combustíveis como a gasolina e óleo diesel, tendo sua demanda aumentada por conta de novas legislações ambientalmente mais restritivas. O hidrogênio é normalmente encontrado na natureza associado a outros elementos químicos, como a água ou os hidrocarbonetos, sendo necessária a aplicação de processos específicos para sua obtenção. Considerada a rota mais econômica para a produção de hidrogênio, o processo de reforma a vapor do gás natural é avaliado pela aplicação da metodologia de análise exergética e termoeconômica, a fim de determinar a eficiência exergética do processo e o custo de produção do hidrogênio. Este custo de produção é muito sensível ao custo do gás natural, fato que pode prejudicar a competitividade desta rota de produção e, consequentemente, abrir a possibilidade de investir na produção de hidrogênio através de tecnologias alternativas. A unidade de geração de hidrogênio estudada está presente em uma das refinarias da Petrobras e sua produção destina-se à remoção do enxofre presente no óleo diesel. Uma planta síntese do processo foi elaborada e as eficiências exergéticas dos componentes foram determinadas. Em seguida, foi realizada uma análise econômica para determinar o custo de construção, operação e manutenção da planta. Com base nos resultados obtidos, aplicou-se a metodologia de análise termoeconômica para determinar o custo de produção de hidrogênio. Dois tipos de custo foram determinados, o custo atual (ou atualizado) de produção, que indica o custo corrente (2010) do produto, e o custo nivelado, que leva em consideração a produção total prevista ao longo vida útil da planta. Para um custo de gás natural igual a 9,11 US$/GJ, o custo de produção do hidrogênio em base exergética foi igual a 17,36 US$/GJ (2.093,13 US$/t) para o valor atual e 25,35 US$/GJ (3.056,97 US$/t) para o valor nivelado. Por fim, estes valores são comparados com outros custos de produção de hidrogênio presentes na literatura.
Pure hydrogen (H2) is an useful gas in chemical and petrochemical industries because it reacts easily with several other elements. On refineries, hydrogen is used to sequestrate sulphur from diesel and gasoline. Emission restrictions regard to fossil fuels are rising the world hydrogen demands. In spite of its abundance, hydrogen is normally found associated with other chemical species like water or hidrocarbons like methane or butane. Some especific processes are required to obtain pure hydrogen. Considered the most economic production route, the natural gas reforming process is analyzed by exergetic and thermoeconomic methods in order to determine the efficiencies and the hydrogen production cost. The hydrogen production cost is very sensitive to the cost of natural gas, which has suffered constant increases due to rising demand. This fact opens the possibility of using technologies that were previously considered economically unviable. The hydrogen unit studied was constructed in one of the Petrobras refineries, and the hydrogen produced is for the removal of sulfur in diesel oil. Based on project documents exergetic efficiencies of each component were determined. After that, an economic analysis was conducted in order to determine the construction, operation and maintenance costs of the whole plant. Two types of cost were determined, the actual cost production, which indicates the current cost product (2010), and the levelized cost, which takes into account the total production over life of the plant. Considering a natural gas cost equal to 9.11 US$/GJ, it was obtained an actual hydrogen production cost of 17.36 US$/GJ (2,093.13 US$/t) and a levelized cost of 25.35 US$/GJ (3,056.97 $/t). These values were compared with some hydrogen production costs presents on scientific papers and related references.

Desalination is one of the proposed methods to meet the ever increasing water demands. It can be subdivided into two broad categories, thermal based desalination and electricity based desalination. Multi-effect Distillation (MED), Multi-Stage Flashing (MSF), Membrane Distillation (MD) fall under former and Reverse Osmosis (RO), Electro-Dialysis (ED) fall under later. MD offers an attractive solution for seawater as well as brackish water distillation. It shows highly pure yields, theoretically 100% pure. The overall construction of a MD unit is way simpler than any other desalination systems. MD is a thermally driven diffusion process where desalination takes places in the form of water vapor transport across the membrane. It has low second law efficiency due to parasitic heat losses. The objective of the first part of the investigation is to thoroughly analyze a Direct Contact Membrane Distillation (DCMD) system from the view point of yield and exergy. The insights from exergy analysis are used in a design study, which is used for performance optimization. The first part concludes with a design procedure and design windows for large scale DCMD construction. In the second part of the investigation, focus is moved to waveguide solar energy collector. The idea behind an ideal waveguide is to reduce the complexity of modeling solar energy collection. The mathematical model provided in this analysis can be extended to a family of non-imaging optics in solar energy and serves as a benchmarking analysis tool. A waveguide is suitable for low temperature operations due to limitations on maximum continuous temperature of operation. Thus, it becomes an ideal solution for DCMD applications. A levelized cost analysis is presented for a waveguide powered DCMD plant of a 30,000 capacity. A combination of waveguide and DCMD shows levelized cost of water at $1.80/m3, which is found to be lower than previously reported solar desalination water costs.
Master of Science

El elevado costo de los combustibles líquidos en la actualidad y la alta contaminación producto de su combustión, hace necesario buscar nuevas alternativas energéticas. En consecuencia, el gas natural se presenta como la mejor alternativa para reducir costos energéticos con bajo impacto ambiental. Estos fundamentos son los que conllevan a la búsqueda de alternativas de solución al suministro energético diferenciado tal como el Gas Natural Comprimido (GNC). En el presente documento se realiza el estudio Másico, Energético, Exergético y de Costos (EXCEM por sus siglas en Ingles) de una Unidad de Compresión de Gas Natural (UCGN), componente principal de una Estación de Carga de GNC) con el Objetivo de determinar los costos de producción del GNC y su variación respecto de variables operativas del equipo. Para esto se eatableció la siguiente hipotesis: “El incremento de la Eficiencia Exergética de la Unidad de Compresión de Gas Natural de una Estación de Carga de GNC reduce del costo de producción de GNC.” Basados en esto se plantea como objetivo principal determinar la relación existente entre la Eficiencia Exergética de la UCGN en una Estación de carga de GNC y el costo de producción de GNC. Para llegar al objetivo principal se plantean como objetivos secundarios identificar los subsistemas energéticos de la UCGN, así como sus Flujos de Energía mediante una metodología de evaluación aplicable a sistemas energéticos (EXCEM) para que a través del establecimiento de las Bases Teóricas que gobiernan el funcionamiento de la UCGN se puedan determinar sus principales parámetros de funcionamiento y cuantificar los procesos de conversión de Energía y como estos influyen en los costos asociados a la producción de GNC. Los resultados de este estudio se basan en tres puntos de operación los cuales permiten determinar un análisis de sensibilidad del Costo Exergético de GNC y la Eficiencia Exergética de la UCGN en donde se demuestra que la hipótesis planteada en esta tesis es correcta. Finalmente, como conclusión principal se establece que la reducción del Costo de producción de GNC para un ciclo de trabajo es proporcional al incremento de la eficiencia exergética del sistema.
Tesis

Within a production machine, various electromechanical and pneumatic structures can be used for drive tasks. As these drive technologies can often replace each other, the energy efficiency, performance and TCO of pneumatic drives must be permanently enhanced to remain competitive. There is a large number of known measures for the reducing their energy consumption, e.g. minimizing of filling volumes, energy saving circuits etc. However, these measures are mainly considered separately and the possible overall energy saving effect resulting from their combination is rarely taken into account. The main goal of this paper is therefore to explore the possible combinations of pneumatic energy saving measures and their cumulative saving effect. Due to the fact that some measures are mutually exclusive (e.g. a general pressure reduction in properly sized drive), each combination should be considered separately. To evaluate their efficiency plausibly, a comprehensive assessment is required that contains both the total cost of ownership analysis (TCO) and a mechanical properties assessment. The presented comprehensive approach of the task analysis can serve as example of how an optimal drive configuration for the specific task can be found, thus creating a basis for solving constructive challenges in designing of pneumatic automation systems.

Stand-alone hybrid energy systems are an attractive option for remote communities without a connection to a main power grid. However, the intermittent nature of solar and other renewable sources adversely affects the reliability with which these systems respond to load demands. Hybridisation, achieved by combining renewables with combustion-based supplementary prime movers, improves the ability to meet electric load requirements. In addition, the waste heat generated from backup Internal Combustion Engines or Micro Gas Turbines can be used to satisfy local heating and cooling loads. As a result, there is an expectation that the overall efficiency and Greenhouse Gas Emissions of stand-alone systems can be significantly improved through waste heat recovery. The aims of this PhD project are to identify how incremental increases to the hardware complexity of hybridised stand-alone energy systems affect their cost, efficiency, and CO2 footprint. The research analyses a range of systems, from those designed to meet only power requirements to others satisfying power and heating (Combined Heat and Power), or power plus both heating and cooling (Combined Cooling, Heating, and Power). The majority of methods used focus on MATLAB-based Genetic Algorithms (GAs). The modelling deployed finds the optimal selection of hardware configurations which satisfy single- or multi-objective functions (i.e. Cost of Energy, energy efficiency, and exergy efficiency). This is done in the context of highly dynamic meteorological (e.g. solar irradiation) and load data (i.e. electric, heating, and cooling). Results indicate that the type of supplementary prime movers (ICEs or MGT) and their minimum starting thresholds have insignificant effects on COE but have some effects on Renewable Penetration (RP), Life Cycle Emissions (LCE), CO2 emissions, and waste heat generation when the system is sized meeting electric load only. However, the transient start-up time of supplementary prime movers and temporal resolution have no significant effects on sizing optimisation. The type of Power Management Strategies (Following Electric Load-FEL, and Following Electric and Following Thermal Load- FEL/FTL) affect overall Combined Heating and Power (CHP) efficiency and meeting thermal demand through recovered heat for a system meeting electric and heating load with response to a specific load meeting reliability (Loss of Power Supply Probability-LPSP). However, the PMS has marginal effects on COE. The Electric to Thermal Load Ratio (ETLR) has no effects on COE for PV/Batt/ICE but strongly affects PV/Batt/MGT-based hybridised CHP systems. The higher thermal than the electric loads lead to higher efficiency and better environmental footprint. Results from this study also indicate that for a stand-alone hybridised system operating under FEL/FTL type PMS, the power only system has lower cost compared to the CHP and the Combined Cooling, Heating, and Power (CCHP) systems. This occurs at the expense of overall energy and exergy efficiencies. Additionally, the relative magnitude of heating and cooling loads have insignificant effects on COE for PV/Batt/ICE-based system configurations, however this substantially affects PV/Batt/MGT-based hybridised CCHP systems. Although there are no significant changes in the overall energy efficiency of CCHP systems in relation to variations to heating and cooling loads, systems with higher heating demand than cooling demand lead to better environmental benefits and renewable penetration at the cost of Duty Factor. Results also reveal that the choice of objective functions do not affect the system optimisation significantly.

In the last half century, the aerospace industry has seen a dramatic paradigm shift from a focus on performance-at-any-cost to product economics and value. The steady increase in product requirements, complexity and global competition has driven aircraft manufacturers to seek broad portfolios of advanced technologies. The development costs and cycle times of these technologies vary widely, and the resulting design environment is one where decisions must be made under substantial uncertainty. Modeling and simulation have recently become the standard practice for addressing these issues; detailed simulations and explorations of candidate future states of these systems help reduce a complex design problem into a comprehensible, manageable form where decision factors are prioritized. While there are still fundamental criticisms about using modeling and simulation, the emerging challenge becomes ``How do you best configure uncertainty analyses and the information they produce to address real world problems?” One such analysis approach was developed in this thesis by structuring the input, models, and output to answer questions about the risk and economic impact of technology decisions in future aircraft programs. Unlike other methods, this method placed emphasis on the uncertainty in the cumulative cashflow space as the integrator of economic viability. From this perspective, it then focused on exploration of the design and technology space to tailor the business case and its associated risk in the cash flow dimension. The methodology is called CASSANDRA and is intended to be executed by a program manager of a manufacturer working of the development of future concepts. The program manager has the ability to control design elements as well as the new technology allocation on that aircraft. She is also responsible for the elicitation of the uncertainty in those dimensions within control as well as the external scenarios (that are out of program control). The methodology was applied on a future single-aisle 150 passenger aircraft design. The overall methodology is compared to existing approaches and is shown to identify more economically robust design decisions under a set of at-risk program scenarios. Additionally, a set of metrics in the uncertain cumulative cashflow space were developed to assist the methodology user in the identification, evaluation, and selection of design and technology. These metrics are compared to alternate approaches and are shown to better identify risk efficient design and technology selections. At the modeling level, an approach is given to estimate the production quantity based on an enhanced Overall Evaluation Criterion method that captures the competitive advantage of the aircraft design. This model was needed as the assumption of production quantity is highly influential to the business case risk. Finally, the research explored the capacity to generate risk mitigation strategies in to two analysis configurations: when available data and simulation capacity are abundant, and when they are sparse or incomplete. The first configuration leverages structured filtration of Monte Carlo simulation results. The allocation of design and technology risk is then identified on the Pareto Frontier. The second configuration identifies the direction of robust risk mitigation based on the available data and limited simulation ability. It leverages a linearized approximation of the cashflow metrics and identifies the direction of allocation using the Jacobian matrix and its inversion.

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Introdu??o: O exerc?cio f?sico ? considerado uma estrat?gia fundamental no tratamento da obesidade por promover aumento no d?ficit cal?rico. Evid?ncias recentes sugerem que o exerc?cio de alta intensidade pode induzir altera??es fisiol?gicas que diminuem o apetite, contribuindo para redu??o da ingest?o cal?rica, fen?meno conhecido como anorexia induzida pelo exerc?cio (AIE). Objetivo: comparar o efeito agudo do exerc?cio intervalado de alta intensidade (EIAI) e exerc?cio cont?nuo de intensidade moderada (ECMI) sobre o consumo energ?tico e percep??o do apetite em homens com obesidade. M?todos: A pesquisa caracterizou-se como um ensaio cl?nico randomizado com delineamento cruzado. Quinze volunt?rios (31,0 ? 6,1 anos, 31,0 ? 6,0 kg/m?, 40,1 ? 2,2% de gordura corporal) foram submetidos a tr?s sess?es experimentais, separadas por sete dias: I) EIAI (10 x 1 min a 90% da frequ?ncia card?aca m?xima [FCm?x] + 1 min recupera??o ativa), II) ECMI (20 min a 70% da FCm?x) e III) Controle (sem exerc?cio). Uma refei??o padronizada foi oferecida 60 min antes de cada sess?o. A percep??o subjetiva do apetite (fome, saciedade, plenitude e perspectiva de consumo alimentar) foi avaliada por meio de uma escala visual anal?gica (EVA) em tr?s momentos: 1) pr?-sess?o, 2) p?s-sess?o e 3) uma hora ap?s sess?o. O consumo alimentar ad libitum foi analisado uma hora ap?s as sess?es experimentais e controle, por meio de registro pesado e o consumo alimentar ao longo do dia da sess?o (24 h) foi avaliado por meio de um registro alimentar estimado. A ANOVA two-way com medidas repetidas foi utilizada para analisar poss?veis diferen?as entre as condi??es e momentos na percep??o do apetite e uma ANOVA de medidas repetidas para analisar as diferen?as entre as condi??es no consumo alimentar ad libitum e 24 h. Resultados: N?o houve diferen?as significativas na percep??o de fome [F(1,3, 17,5)=0,00, p=0,972], saciedade [F(1,3, 17,5)=0,00, p=0,972], plenitude [F(2, 28)=0,13, p=0,876] e perspectiva de consumo [F(2, 28)=0,76, p=0,476] entre as condi??es, bem como n?o foram identificadas diferen?as significativas no consumo energ?tico na refei??o ad libitum: CON (674,5 ? 252,1), ECMI (666,7? 213,8) e EIAI (689,6? 263,8kcal) [F (2, 28)=0,13, p=0,877] e ao longo do dia da sess?o: CON (2857,6 ? 867,2), ECMI (2608,5? 595) e EIAI (2556,1? 489,5kcal) [F (2, 28) = 1,54, p=0,233]. Conclus?o: Uma sess?o de EIAI e ECMI n?o modificou o apetite e o consumo energ?tico ap?s 60 min e ao longo do dia em homens com obesidade.
Introduction: Physical exercise is considered a fundamental strategy in the treatment of obesity by promoting increase in the caloric deficit. Recent evidence suggests that high-intensity exercise can induce physiological changes that suppress appetite, decreasing caloric intake, a phenomenon known as exercise-induced anorexia (EIA). Objective: compare the acute effect of high intensity interval exercise (HIIE) and continuous moderate intensity exercise (ECM) on energy intake and appetite perception in obese men. Methods: The study was characterized as a randomized clinical trial in cross-over design. Fifteen volunteers (31.0 ? 6.1 years, 31.0 ? 6.0 kg/ m?, 40.1 ? 2.2% body fat) underwent three experimental sessions, seven days apart: I) HIIE ( 10x 1 min at 90% of maximal heart rate [HRmax] + 1 min active recovery), II) ECM (20min to 70% of HRmax) and III) Control (without exercise). A standardized meal was offered 60 min before each session. Appetite perception (hunger, satiety, fullness and perspective food consumption) were evaluated through a visual analogue scale (VAS) in three moments: 1) Pre-session, 2) Post-session and 3) one hour after session. Energy intake was assessed one hour after session with an ad libitum meal and the consumption throughout the day (24hrs) was analyzed with a estimated food record. ANOVA Two-way with repeated measures was used to analyze the differences between conditions and moments on appetite perception and ANOVA with repeated measures to assess the differences between conditions on energy intake in ad libitum and 24hrs. Results: There were no significant differences on hunger [F (1.3, 17.5) = 0.00, p = 0.972], satiety [F (1.3, 17.5) = 0.00, p = 0.972], fullness [F (2, 28) = 0.13, p = 0.876] and prospective food consumption [F (2, 28) = 0.76, p = 0.476] between conditions. As well as no significant differences on energy intake were observed during ad libitum meal: CON (674,5 ? 252,1), ECM (666,7? 213,8) e HIIE (689,6? 263,8kcal) [F (2, 28) = 0.13, p = 0.877] and throughout the day CON (2857,6 ? 867,2), ECM (2608,5? 595) e HIIE (2556,1? 489,5kcal) [F (2, 28) = 1.54, p = 0.233].Conclusion: A single session of HIIE and ECM did not modified appetite and energy intake 60 min after and during the day following exercise in obese man.

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O exerc?cio intervalado de alta intensidade tem sido apontado como op??o para o aumento da pr?tica da atividade f?sica al?m de ser sugerido no manejo terap?utico de diversas condi??es como diabetes mellitus e insufici?ncia card?aca. Contudo, o conhecimento pleno das suas repercuss?es fisiol?gicas e dos par?metros que possam trazer maior seguran?a quanto ? sua prescri??o; em especial os efeitos a curto e m?dio prazo (24 horas ap?s o exerc?cio) sobre a recupera??o do exerc?cio, necessitam ser esclarecidos. O objetivo do presente trabalho ? avaliar a repercuss?o de uma sess?o de exerc?cio aer?bico cont?nuo e intervalado no controle auton?mico card?aco imediato e em m?dio prazo (24 horas), atrav?s da avalia??o da variabilidade da frequ?ncia card?aca (VFC). Trata-se de um ensaio cl?nico randomizado do tipo crossover onde indiv?duos jovens saud?veis e com baixo n?vel de atividade f?sica tiveram a VFC de 24 horas mensurada atrav?s de frequenc?metro e aceler?metro port?til (eMotion HRV 3D, Kuopio, Finl?ndia) antes e ap?s sess?o de exerc?cio aer?bio cont?nuo (60-70% FCmax, 21min.) e intervalado (ciclo 1 min. a 80-90% FCmax, 2 min. a 50-60% FCmax, dura??o 21 min.). A VFC foi avaliada nos dom?nio tempo e frequ?ncia e o balan?o simpatovagal determinado pela raz?o LF/HF. Avalia??o n?o linear foi calculada pela entropia de Shannon. O dados demonstraram retardo na recupera??o imediata da frequ?ncia card?aca p?s exerc?cio e menor FC 24 horas comparados a valores pr? interven??o, principalmente no exerc?cio intervalado. Houve tend?ncia ? maior predom?nio e valores de ?ndices representantes da estimula??o simp?tica durante o dia no grupo de exerc?cio intervalado; contudo, sem signific?ncia estat?stica. O resultados do estudo auxiliam no esclarecimento das repercuss?es do exerc?cio intervalado nas 24 horas que sucedem a interven??o permitindo par?metros para prescri??o e futura avalia??o de grupos de indiv?duos com patologias metab?licas e cardiovasculares.
The high-intensity interval exercise has been described as an option for increasing physical activity and its use also being suggested in the therapeutic management of many conditions such as diabetes mellitus and heart failure. However, the knowledge of its physiological effects and parameters that can assure greater safety for interval exercise prescription; especially its effect on short- and medium-term (24 hours after exercise) exercise recovery, need to be clarified. This study objective was to evaluate the effect of continuous and interval aerobic exercise on the cardiac autonomic control immediate and medium term (24 hours), by assessing heart rate variability (HRV). The present study is a randomized crossover clinical trial in which healthy young individuals with low level of physical activity had the VFC 24 hours measured by a heart rate sensor and portable accelerometer (3D eMotion HRV, Kuopio, Finland) before and after continuous aerobic exercise (60-70% HR max, 21 min.) and interval exercise (cycle 1 min. 80-90% HR max, 2 min. at 50-60% HR max, duration 21 min.). HRV was measured in the time and frequency domain and the sympathovagal balance determined by the ratio LF / HF. Nonlinear evaluation was calculated by Shannon entropy. The data demonstrated delayed heart rate recovery immediate after exercise and lower HR after 24 hours compared to pre intervention values, especially in the interval exercise group. There was a tendency to higher predominance and representatives index values of sympathetic stimulation during the day in interval exercise group; however, without statistical significance. The study results help to clarify the effects of interval exercise on the 24 hours following interval exercise, setting parameters for prescription and for further evaluation of groups with metabolic and cardiovascular diseases.

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Introdu??o: O excesso de gordura corporal ? associado ? inflama??o cr?nica de baixo grau e uma maior incid?ncia de doen?as infecciosas. Estudos recentes, indicam que o exerc?cio intervalado de alta intensidade (EIAI) ? uma estrat?gia eficiente em fun??o do tempo para melhorar par?metros de sa?de de indiv?duos com obesidade. No entanto, pouco ? conhecido sobre o efeito de uma sess?o de EIAI no equil?brio de citocinas pro e anti-inflamat?rias em obesos. Objetivo: O objetivo do presente estudo foi comparar uma ?nica sess?o de EIAI e exerc?cio cont?nuo de moderada intensidade (ECMI) sobre os n?veis s?ricos de interferon-y (INF-y), interleucina 4 e 6 (IL-4) (IL-6) e INF-y/IL-4 em homens com obesidade. M?todos: Dez homens com obesidade (IMC>30 kg/m?) foram submetidos a tr?s sess?es experimentais com uma semana de intervalo em ordem aleat?ria: 1) EIAI: 10 x 60 s a 90% da FCm?x alternados por 60 s de recupera??o ativa; 2) ECMI: 20 min a 70% da FCmax; 3) Controle. As coletas de sangue para analisar os n?veis s?ricos de citocinas foram realizadas nos momentos pr?, p?s e 60 min ap?s as sess?es de exerc?cio ou controle. Os dados foram apresentados em m?dia ? DP. ANOVA fatorial com medidas repetidas e post hoc de Bonferoni foi utilizado para avaliar as diferen?as entre os momentos e condi??es de exerc?cio. O n?vel de signific?ncia aceito foi de P< 0.05. Resultados: O EIAI reduziu os n?veis de INF-y imediatamente ap?s o exerc?cio (41,09 ? 14,99; P=0,032) e 60 min ap?s o exerc?cio (43,45 ? 11,76; P=0,003) em rela??o ao pr?-exerc?cio (46,64 ? 13,14), ao mesmo tempo que promoveu aumento nos n?veis de IL-4 imediatamente ap?s o exerc?cio (36,47 ? 11,09; P=0,007) em rela??o ao pr?-exerc?cio (32,04 ? 8,5). O ECMI promoveu aumento nos n?veis de INF-y imediatamente ap?s o exerc?cio (47,48 ? 8,42; P=0,025) e 60 min ap?s o exerc?cio (50,13 ? 7,99; P=0,004) em rela??o ao valor pr?-exerc?cio (44,21 ? 8,11). Ambas as condi??es de exerc?cio aumentaram os n?veis de IL-6 at? 60 min ap?s o exerc?cio (P<0.05). A raz?o INF-Y/IL-4 reduziu imediatamente ap?s (1,24 ? 0,60; P=0,002) e 60 min ap?s o exerc?cio (1,32 ? 0,53; P=0,005) em rela??o ao pr?-exerc?cio (1,58 ? 0,64) apenas para o EIAI. Conclus?o: Uma sess?o de EIAI induziu um padr?o de resposta anti-inflamat?ria e est? associado a preju?zos na resposta imune intracelular contra pat?genos. Por outro lado, uma breve sess?o de ECMI induziu altera??es no padr?o de citocinas seguindo um padr?o pr?-inflamat?rio o que pode favorecer ? melhora da resposta imune intracelular em homens com obesidade.
Introduction: The excess of body fat is associated with chronic low-grade inflammation and high rates of infectious disease. Emerging evidences indicate that high intensity interval exercise (HIIE) is a time-efficient approach to promote health in obese population. However, little is known about the influence of HIIE on pro and anti-inflammatory cytokine balance in obesity. Purpose: Our purpose was to compare the acute effects of HIIE and moderate-intensity continuous exercise (MICE) on cytokine levels, include interferon-y (INF-y), interleukin 4 and 6 (IL-4) (IL-6) levels and INF-y/IL-4 ratio in obese males. Methods: Ten obese males (BMI>30 kg/m?) were submitted into two experimental sessions with a week interval in a randomized order: 1) HIIE: 10 x 60 s at 90% of HRm?x interspersed by active recovery; 2) MICE: 20 min at 70% of HRmax;. Cytokines was analyzed before, immediately after and 60 min after-exercise. Data was presented in mean ? SD. ANOVA 2-way with repeated measures and post hoc Bonferoni was used to assess differences between moments and exercise conditions. Statistical significance was accepted at a p value of ? 0.05. Results: The HIIE results in decreased INF-Y levels immediately after-exercise (41,09 ? 4,74; P=0,032) and 60 min after-exercise (43,45 ? 3,72) (P=0,003) compared with before-exercise (46,64 ? 4,15), while an significant elevation in IL-4 levels was observed immediately after-exercise (36,47 ? 3,5) (P=0,007). The MICE results in increase of INF-Y levels after exercise (P=0,025) and 60 min post-exercise (P=0,004). Both exercise conditions results in increase of IL-6 levels after exercise (P<0.05). The INF-Y/IL-4 ratio decreases immediately after (P=0,002) and 60 min after-exercise (P=0,005) only for HIIE. Conclusion: HIIE induces imbalance in INF-Y/IL-4 ratio 60 min after exercise following an anti-inflammatory pattern. For other hand, MICE did not promote imbalance in INF-Y/IL-4 to 60 min after exercise in obese males.

The change in climate as a consequence of anthropogenic activities is a subject ofmajor concerns. In order to reduce the amount of greenhouse gas emissions inthe atmosphere, the utilization of renewable, fossil-free power generationapplications becomes inevitable. Geothermal and solar energy play a major rolein covering the increased demand for renewable energy sources of today’s andfuture’s society. A special focus hereby lies on the Concentrating Solar Powertechnologies and different geothermal concepts. The costs for producingelectricity through Concentrating Solar Power and therefore Parabolic Trough Collectorsas well as geothermal conversion technologies are still comparatively high. Inorder to minimize these expenses and maximize the cycle’s efficiency, thepossible synergies of a hybridization of these two technologies becomeapparent. This thesis therefore investigates the thermodynamic and economicbenefits and drawbacks of this combination from a global perspective. For that,a Parabolic Trough Collector system is combined with the geothermal conversionconcepts of Direct Steam, Single and Double Flash, Organic Rankine as well asKalina Cycles. The solar integrations under investigation are Superheat,Preheat and Superheat & Reheat of the geothermal fluid. The thermodynamicanalysis focuses on the thermal and utilization efficiencies, as well as therequired Parabolic Trough Collector area. The results indicate that in the caseof the Superheat and Superheat & Reheat setup, the thermal efficiency canbe improved for all geothermal concepts in comparison to their correspondinggeothermal stand-alone case. The Preheat cases, with the major contributionfrom solar energy, are not able to improve the cycle’s thermal efficiencyrelative to the reference setup. From an exergy perspective the findings varysignificantly depending on the applied boundary conditions. Still, almost allcases were able to improve the cycle’s performance compared to the referencecase. For the economic evaluation, the capital investment costs and thelevelized costs of electricity are studied. The capital costs increasesignificantly when adding solar energy to the geothermal cycle. The levelizedelectricity costs could not be lowered for any hybridization case compared tothe reference only-geothermal configurations. The prices vary between20.04 €/MWh and 373.42 €/MWh. When conducting a sensitivity analysison the solar system price and the annual mean irradiance, the Kalina Superheatand Superheat & Reheat, as well as the Organic Rankine Preheathybridizations become cost competitive relative to the reference cases.Concluding, it is important to remark, that even if the hybridization of the ParabolicTrough and the different geothermal concepts makes sense from a thermodynamicperspective, the decisive levelized costs of electricity could not be improved.It is, however, possible that these costs can be further reduced under speciallocal conditions, making the addition of Parabolic Trough solar heat tospecific geothermal concepts favorable.

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The fluctuacion force has been increasingly used in studies with elderly as a good predictor of performance and functionality of the motor. However, most analyzes the fluctuation of force in one session. Thus, identifying the minimum amount of sessions needed for familiarization with the fluctuation strength in isometric exercise become relevant. Furthermore, to investigate the effects of applying transcranial direct current stimulation (tDCS) associated with regular exercise on rates fluctuation task force is extremely important. In the first experiment, volunteers were subjected to a protocol marked by a familiarization session to establish the parameters of VCM and eight sessions with intensity of 30% MVC in office. It was observed that two familiarization sessions are required so there is a fluctuation stabilizing force. In experiment II, subjects performed an isometric contraction before and after applying tDCS (cathode, anode and sham) applied to M1. ETCC anodic effectively contributed to reducing the fluctuation of force during isometric exercise in the elderly, while the cathodic caused the increased levels of strength fluctuation. It was concluded that there is a need to implement a familiarization protocol with at least two sessions to avoid possible misunderstandings of measurements in tests of fluctuacion force. Besides that tDCS interfered with the behavior of the oscillations of force, with cathodic promoting increased fluctuation strength and anodic contributed to greater stability, demonstrating the potential of this technique neuromodulation associated with exercise as rehabilitation tools
A flutua??o de for?a tem sido cada vez mais utilizada em estudos com idosos como um bom preditor de desempenho e funcionalidade da motricidade. No entanto, a maioria analisa a flutua??o de for?a em sess?o ?nica. Assim, identificar a quantidade de sess?es m?nimas necess?rias para a familiariza??o ao teste de flutua??o de for?a em exerc?cio isom?trico tornar-se pertinente. Al?m disso, investigar os efeitos da aplica??o da Estimula??o Transcraniana por Corrente Cont?nua (ETCC) associada ? pr?tica regular de exerc?cio sobre os ?ndices de flutua??o de for?a ? tarefa de extrema relev?ncia. No experimento I, volunt?rias foram submetidas a um protocolo de familiariza??o marcado por uma sess?o para estabelecer os par?metros de CVM e oito sess?es com intensidade de 30%CVM em exerc?cio. Observou-se que duas sess?es de familiariza??o s?o necess?rias para que haja uma estabiliza??o da flutua??o de for?a. No experimento II, volunt?rias realizaram uma contra??o isom?trica antes e ap?s a aplica??o de ETCC (cat?dica, an?dica e sham) aplicada ao M1. ETCC an?dica contribuiu efetivamente para a redu??o da flutua??o de for?a em idosos durante exerc?cio isom?trico, enquanto que a cat?dica provocou o aumento dos ?ndices de flutua??o de for?a. Concluiu-se que h? a necessidade de aplica??o de um protocolo de familiariza??o com pelo menos duas sess?es para que sejam evitados equ?vocos de mensura??es em testes de avalia??o da flutua??o de for?a. Al?m de que a ETCC interferiu no comportamento das oscila??es de for?a, com cat?dica promovendo aumento da flutua??o de for?a e a an?dica contribuiu para uma maior estabilidade, demonstrando o potencial dessa t?cnica de neuromodula??o associada ao exerc?cio como ferramentas de reabilita??o

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A estimula??o transcraniana por corrente cont?nua (ETCC) ? uma t?cnica n?o invasiva que apresenta caracter?sticas anti-fadigante e analg?sica. Com o objetivo de testar seus efeitos sobre a diminui??o da for?a e do aparecimento da dor muscular de in?cio tardio (DMIT), apresentados ap?s um evento de dano muscular induzido pelo exerc?cio (DMIE), foi utilizado um estudo cl?nico de car?ter experimental, controlado, randomizado e duplo-cego. A amostra foi composta por 24 jovens do sexo masculino, aparentemente saud?veis (19,7?1,8 anos; 23,6?3,65 IMC), os quais foram alocada, de forma aleat?ria e estratificada, nos seguintes grupos: G1: grupo controle; G2: grupo de estimula??o ap?s o dano e G3: grupo com estimula??o antes e ap?s o dano muscular. Os dados foram submetidos ? estat?stica descritiva e an?lise de vari?ncia ANOVA, adotando-se um n?vel de signific?ncia de 5%. O aumento nos n?veis s?ricos de CK (56.18%) e LDH (24,15%) comprovou a ocorr?ncia do DMIE. Em contrapartida, ap?s a an?lise de vari?ncia para compara??o dos tratamentos aplicados, pode-se observar que n?o houve diferen?as significativas nos n?veis de CK (p= 0,3514) e for?a muscular (p= 0,9702). A DMIT transcorreu como esperado, mas sem diferen?a significativa entre os grupos (p= 0,4861). Estes dados demonstraram que a ETCC n?o foi capaz de modular a DMIT e a diminui??o da for?a muscular ap?s o DMIE em jovens aparentemente saud?veis

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Pulmonary Rehabilitation, especially due to aerobic exercise, positive impact in reducing morbidity/mortality of patients with COPD, however the economic impact with costs of implementing simple programs of aerobic exercise are scarce. This is a blind randomized clinical trials, which aimed to evaluate the costs and benefits of a simple program of aerobic exercise in individuals with COPD, considering the financial costs of the Public Health System and its secondary endpoints. We evaluated lung function, the distance walked during six minutes of walking, the respiratory and peripheral muscle strength, quality of life related to health (QLRH), body composition and level of activity of daily living (ADL) before and after eight weeks of an aerobic exercise program consisting of educational guidance for both groups, control and intervention and supervised walks to the intervention group. The health costs generated in both groups were calculated following table Brazilian Public Health System. The sample consisted of forty patients, two being excluded in the initial phase of desaturation during the walk test six minutes. Were randomized into control and intervention group thirty-eight patients, three were excluded from the control group and one was excluded from the intervention group. At the end, thirty-four COPD comprised the sample, 16 in the control group and 18 in the intervention group (FEV1: 50.9 ? 14% pred and FEV1: 56 ? 0.5% pred, respectively). After for intervention, the intervention group showed improvement in meters walked, the sensation of dyspnea and fatigue at work, BODE index (p <0.01) in QLRH, ADL level (p <0.001) as well as increased strength lower limbs (p <0.05). The final cost of the program for the intervention group was R $ 148.75, including: assessments, hiking supervised by a physiotherapist and reassessments. No patient had exacerbation of IG, while 2 patients in the CG exacerbated, generating an average individual cost of R $ 689.15. The aerobic exercises in the form of walking showed significant clinical benefits and economic feasibility of its implementation, due to low cost and easy accessibility for patients, allowing them to add their daily practice of aerobic exercises
A Reabilita??o Pulmonar, especialmente devido aos exerc?cios aer?bios, impacta positivamente na redu??o da morbidade/mortalidade do paciente com DPOC, entretanto o impacto econ?mico com custos de da implementa??o de programas simples de exerc?cios aerobios s?o escassos. Trata-se de um ensaio cl?nico aleat?rio controlado cego, que objetivou avaliar os custos e os benef?cios de um programa simples de exerc?cios aer?bios em indiv?duos com DPOC, considerando os custos financeiros do Sistema P?blico de Sa?de e seus desfechos secund?rios. Foram avaliadas a fun??o pulmonar, a dist?ncia percorrida no teste da caminhada dos 6 minutos, a for?a muscular respirat?ria e perif?rica, a qualidade de vida relacionada ? sa?de (QVRS), a composi??o corporal e o n?vel de atividade de vida di?ria (AVD) antes e ap?s oito semanas de um programa de exerc?cios aer?bicos composto por de orienta??es educacionais para ambos os grupos, controle e interven??o e caminhadas supervisionadas para o grupo interven??o. Os custos sanit?rios gerados em ambos os grupos foram calculados seguindo tabela do Sistema de Sa?de P?blico Brasileiro. A amostra foi composta por quarenta pacientes, sendo dois exclu?dos na fase inicial por dessatura??o durante o teste de caminhada de seis minutos. Foram aleatorizados em grupo controle e grupo interven??o trinta e oito pacientes, sendo que tr?s foram exclu?dos do grupo controle e um foi exclu?do do grupo interven??o. Ao final, trinta e quatro DPOC compuseram a amostra, 16 no grupo controle e 18 no grupo interven??o (VEF1: 50.9 ? 14 %pred e VEF1: 56 ? 0.5 %pred, respectivamente). Ap?s para interven??o, o grupo interven??o apresentou melhora nos metros caminhados, na sensa??o de dispneia e fadiga, no trabalho realizado, ?ndice de BODE (p<0.01), na QVRS, no n?vel de AVD (p<0.001) al?m de incremento da for?a dos membros inferiores (p<0.05). O custo final do programa para o grupo interven??o foi de R$ 148.75, incluindo: avalia??es, caminhadas supervisionadas por um fisioterapeuta e as reavalia??es. Nenhum paciente do GI apresentou exacerba??o, enquanto no GC 2 pacientes exacerbaram, gerando um custo individual m?dio de R$ 689.15. Os exerc?cios aer?bios na modalidade de caminhadas demonstraram significantes benef?cios cl?nicos e a viabilidade econ?mica de sua implementa??o, devido ao baixo custo e de f?cil acessibilidade para os pacientes, permitindo que estes possam adicionar as suas atividades di?rias a pr?tica de exerc?cios aer?bios

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Introdu??o: A Reabilita??o Card?aca (RC) tem importante efeito na mortalidade e morbidade dos pacientes com insufici?ncia card?aca (IC) cr?nica, sendo o exerc?cio f?sico uma alternativa para tratamento desse paciente. O tipo de exerc?cio mais estudado para alcan?ar o condicionamento cardiovascular ? o treinamento f?sico cont?nuo. Recentemente t?m-se estudado os efeitos do treinamento intervalar com alta intensidade de exerc?cio, por?m ainda n?o h? consenso sobre a dose e tipo ideal de exerc?cio para esse paciente. O objetivo do presente ensaio cl?nico foi avaliar os efeitos do treinamento aer?bico cont?nuo vs intervalado na capacidade aer?bia e qualidade de vida em pacientes com IC cr?nica. M?todos e Resultados: Dezoito pacientes com IC cr?nica com tratamento medicamentoso otimizado (m?dia de 44,7?13,2 anos; 35,2?8,9% de Fra??o de eje??o de ventr?culo esquerdo [FEVE] e de VO2pico de 20,6?5,3ml/kg/min) foram randomizados em: Grupo Treinamento Intervalado (GTI - 85% da frequ?ncia card?aca de reserva - FCR), Grupo Treinamento Cont?nuo (GTC - 60% da FCR), realizados 3 vezes por 12 semanas (total de 36horas) e Grupo Controle (GC) que recebeu orienta??es sobre a import?ncia da atividade f?sica. Os pacientes foram submetidos a uma avalia??o inicial e final da capacidade aer?bica (Teste de esfor?o cardiopulmonar - TECP) e question?rio de qualidade de vida. Ambos os treinamento foram eficientes para aumentar o VO2pico sendo 15,1% (P=0,02) no GTI e 16,1% (P=0,01) no GTC. Quanto ? qualidade de vida tanto o GTI, quanto o GTC apresentaram melhora quando comparados com o grupo controle (P=0,006). Os eventos de incompatibilidade hemodin?mica durante o TECP (depress?o/manuten??o de press?o arterial sist?lica) foram reduzidos ap?s o treinamento mais no GTC (4 para 1 pacientes) do que no GTI (5 para 3). O risco card?aco tamb?m diminuiu mais no GTC (3 pacientes sairam do risco moderado/grave para o leve ap?s o treinamento) e no GTI apenas 1 pacientes mudou essa categoria. Conclus?o: Ambos os tipos de treinamento foram eficientes em aumentar o condicionamento aer?bico e qualidade de vida neste grupo de pacientes, entretanto no grupo intervalar foram mais frequentes a queda ou manuten??o da press?o arterial sist?lica sugerindo maior incompet?ncia hemodin?mica e maior risco de desenvolver evento card?aco
Background: Cardiac Rehabilitation (CR) has effect on mortality in patients with heart failure (HF) chronic, and the exercise of the treatment of this patient. The most common exercise is ongoing training. Recently we have been studying the effects of interval training, but there is no consensus on the optimal dose of exercise. Objective: To evaluate the effects of interval aerobic training are superior to continuous aerobic training in patients with chronic HF. Methods: The clinical trial evaluated patients through cardiopulmonary test (CPX) and quality of life before and after the RC (3 times / 12 weeks). Patients were randomized into Group Interval Training (GTI - 85% of heart rate reserve - FCR), Continuous Training Group (GTC - 60% of HRR) and control group (CG) who received guidelines. Results: 18 patients were evaluated (mean age 44.7 ? 13.2 years and 35.2 ? 8.9% of left ventricular ejection fraction [LVEF]). Both groups were efficient to increase the peak VO2 and 15.1% (P = 0.02) in GTI and 16.1% (P = 0.01) GTC. As for the quality of life the GTI GTC showed improvement compared to the control group (P = 0.006). Hemodynamic mismatch events during the CPX were reduced after training in more GTC (patients 1 to 4) than in the GTI (5 to 3). Cardiac risk also decreased in the GTC (3 patients left the severe risk to take after training). Conclusion: Continuous training becomes more appropriate for improving fitness with little chance of developing cardiac event patients with chronic HF.

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This work presents results derived from a study related to impact on non-controllable costs in the determination of energy taxes. This is done analyzing tax review practiced by concessionaries responsible for the distribution of electrical energy located in the Northeastern Region of Brazil, between 2003 and 2004. This Region was chosen as a study area due to the researcher s expectation in congregating companies that deliver services to markets that have similar social-economical profiles. A brief explanation related to the restructuring of the electrical sector in Brazil is presented, pointing out that there was privatization of the great majority of these companies. The study also points out the definition of regulating rules in service delivery process. The components of taxes that are practiced by these companies aimed at final consumers, as well as the market as a whole and the revision process that is executed by Ag?ncia Nacional de Energia El?trica ANEEL for the definition of these taxes are demonstrated in the research. A brief historical of the concessionaires that were focus of the research is presented, totaling five companies. Some data used by ANEEL in the tax review process was analyzed as well as data on components of approved taxes. It is concluded that as a media 47, 49% of the components of taxes in the researched companies correspond to the non-controllable costs. These is done considering previous classification by ANEEL in the tax review process. Although, if it is considered that these companies since 2006, by the means of participation in energy auctions are able to negotiate energy prices for their own needs, it is concluded that these concession contracts guarantee the delivery of the service to the costumer in the total tribute. The percentage of non-controllable costs is 16, 27% average of the tax. This means, amongst other information, that the government has a great deal of responsibility in the formation of price practiced by these companies and its target markets
Este trabalho apresenta o resultado de um estudo do impacto dos custos n?o-gerenci?veis na determina??o das tarifas de energia el?trica decorrentes do processo de revis?o tarif?ria, ocorrido nos exerc?cios de 2003 e 2004, nas concession?rias de distribui??o de energia el?trica localizadas na Regi?o Nordeste do Brasil. A escolha da Regi?o Nordeste como ?rea de estudo, deve-se ? expectativa do pesquisador em congregar no estudo empresas que prestem servi?os a mercados com perfis s?cio-econ?mico similares. ? apresentada uma breve explana??o sobre a reestrutura??o do setor el?trico no Brasil, tendo como conseq??ncia a privatiza??o da maioria das distribuidoras de energia e a defini??o das regras de regula??o na presta??o do servi?o. S?o demonstrados os componentes das tarifas de energia el?trica praticadas pelas concession?rias aos consumidores finais de seus mercados e o processo de revis?o tarif?ria executado pela Ag?ncia Nacional de Energia El?trica ANEEL para defini??o dessas tarifas. ? feito um breve hist?rico das concession?rias pesquisadas, num total de cinco companhias. Por fim, s?o discutidos os dados utilizados pela ANEEL no processo de revis?o tarif?ria e analisados os componentes das tarifas aprovadas. Conclui-se que, em m?dia, 47,49% dos componentes das tarifas das empresas pesquisadas correspondem a custos n?o-gerenci?veis, ? luz da classifica??o utilizada pela ANEEL no processo de revis?o tarif?ria. Entretanto, se considerado que as distribuidoras, a partir do exerc?cio de 2006, t?m a capacidade de negociar o pre?o de compra da energia para a totalidade de sua necessidade, participando de leil?es de energia, e que os contratos de concess?o garantem o repasse ao consumidor da totalidade dos tributos, o percentual dos custos n?o-gerenci?veis passa a ser, em m?dia, de 16,27% da tarifa, o que significa, dentre outras informa??es, que o poder p?blico tem uma consider?vel parcela de responsabilidade na forma??o dos pre?os de energia praticados pelas concession?rias em seus mercados de atua??o

The objective of this thesis is to establish the utility and limitations of using exergy (a thermodynamic measure of energy quality, or ability to perform work) as a resource consumption metric, and to investigate what role exergy may play in resource consumption decision-making. To do so, this thesis assessed three exergy-based resource consumption methodologies: the Exergy Replacement Cost; Eco-exergy; and Emergy. Furthermore, fundamental properties of exergy were revisited, including the exergy reference state, and the derivations of both concentration and non-flow exergy. The results of the analysis indicate three significant problem areas with applying exergy toward resource valuation. First, the exergy derivation level conflicts with the resource valuation level regarding important requirements and assumptions: the exergy reference environment is modelled as an infinitely large system in internal chemical equilibrium, and this is in incomparable to the real world; and, the derivation of non-flow exergy values items based solely upon chemical concentrations, whereas at the resource consumption level, work producing items are valuable based primarily upon chemical reactivity. Second, exergy proponents have not adequately addressed the many different and critical perspectives of exergy, including exergy as: harmful or helpful; organizing or disorganizing; a restricted or unrestricted measure of potential useful work; and applied to value systems or specific items. Third, none of the resource consumption methodologies properly apply exergy: the Exergy Replacement Cost primarily focuses on mineral upgrading; Eco-exergy is improperly derived from exergy; and Emergy has switched from being energy-based to exergy-based without any reformulation of the methodology. For the reasons provided above, among others, this author concludes there is currently no justified theoretical connection between exergy and resource value, and that there is a disjunction between how exergy is derived and how it is applied. Non exergy-based applications for the three resource consumption methodologies are proposed.

This thesis presents the optimization of a model of a solar combisystem installed in an energy efficient house in the climate of Montreal, Quebec. The work presented in the thesis includes: 1) A methodology for the optimization of a solar collector system based on four different objective functions; 2) The development of a computer-based platform for combisystem optimization; 3) Recommendations for the optimal configurations of a solar combisystem to minimize life cycle cost, life cycle energy use and life cycle exergy destroyed; and 4) The analysis of the performance of the hybrid stochastic, evolutionary and deterministic optimization approach. The optimizations, using is a hybrid particle swarm and Hooke-Jeeves optimization algorithm, were able to reduce the life cycle cost of the combisystem by 19%, the life cycle energy use by 24%, the life cycle exergy destroyed by 33% and 24% for the technical boundary and physical boundary, respectively. Due to the high cost of the solar collector technologies and the low price of electricity in Quebec, none of the configurations have acceptable financial payback periods. However, all of the configurations have energy payback times within 7 years. For the life cycle exergy destroyed, using the technical boundary favors the use of electricity over solar energy due to the low exergy efficiency of the solar collectors. Using the physical boundary, on the other hand, favors the use of solar energy over electricity.

In this thesis the Copper-Chlorine (Cu-CI) thermochemical cycle and its components as well as operational and environmental conditions are defined, and a comprehensive thermodynamic analysis of a Cu-CI thermochemical cycle, including the relevant chemical reactions, is performed. Also the performance of each component/process is evaluated through energy and exergy efficiencies. Various parametric studies on energetic and exergetic aspects with variable reaction and reference-environment temperatures are carried out. A detailed analysis of the general methodology of cost estimation for the proposed process, including all cost items with their percentages, the factors that affect accuracy, and a scaling method, is also presented.
UOIT

Hydrogen is considered to become a main energy vector in sustainable energy systems to store large amounts of intermittent wind and solar power. In this work, exergy efficiency and cost analyses are conducted to compare pathways of hydrogen generation (PEM, alkaline or solid oxide electrolysis), storage (compression, liquefaction or methanation), transportation (trailer or pipeline) and utilization (PEMFC, SOFC or combined cycle gas turbine). All processes are simulated with respect to their full and part-load efficiencies and resulting costs. Furthermore, load profiles are estimated to simulate a whole year of operation at varying loads. The results show power-to-power exergy efficiencies varying between about 17.5 and 43 %. The main losses occur at utilization and generation. Methanation features both lower efficiency and higher costs than compressed hydrogen pathways. While gas turbines show very high efficiency at full load, their efficiency drops significantly during load-following operation , while fuel cells (especially solid oxide) can maintain their efficiency and exceed the combined cycle gas turbine full-load efficiency. Overall specific costs between 245 €/MWh and 646 €/MWh are resulting from the simulation. Lower costs are commonly reached in chains with higher overall efficiencies. Installation costs are identified as predominant because of the low amount of full-load hours. To decrease the energy storage overall costs of the process chains, the options to use revenue generated by by-products such as oxygen and heat as well as changing the system application scenario are investigated. While the effect of the oxygen sale is negligible, the revenue generated by heat can significantly decrease overall costs. An increase of full-load by accounting for an electrolysis base-load to provide hydrogen for vehicles also shows a significant decreases in costs per stored energy down to 151 €/MWh at 2337 h/a full-load hours. The optimization of the exergy efficiency is performed by analysing physical and heat exergy recovery options such as expansion machines in the gas grid, the use of additional thermodynamic cycles (both Joule and Clausius-Rankine), as well as providing heat for steam electrolysis from compression inter-cooling, methanation or stored heat from a solid oxide fuel cell. The analysis shows that at full-load, process chains using solid oxide electrolysis, compressed hydrogen and a combined cycle gas turbine or a solid oxide fuel cells with a heat exergy recovery cycle can reach exergy efficiencies of 47 % and 45.5 %, respectively. A reversible solid oxide cell systems with metal-hydride heat and hydrogen storage can also reach 46.5 % exergy efficiency. The energy storage costs for these processes can be as low as 35 to 40 €/MWh at full-load. At load-following operation the efficiency of the fuel cell systems is expected to increase.:1 Introduction 22 2 Objective and Structure 24 3 Hydrogen as an Energy Vector 25 3.1 Mobile application focus 25 3.2 Stationary application focus 28 3.3 Studies on energy systems 32 3.4 Conclusion 36 4 Hydrogen Technology Overview 37 4.1 Hydrogen production 37 4.1.1 Electro-chemical hydrogen production 37 4.1.2 Thermo-chemical hydrogen production 42 4.1.3 Biological hydrogen production 46 4.1.4 Other hydrogen production processes 46 4.1.5 Gas cleaning 47 4.2 Hydrogen storage 49 4.2.1 Chemical compounds 49 4.2.2 Metal hydride 50 4.2.3 Physical storage 52 4.3 Hydrogen transport 54 4.3.1 Gas grid 54 4.3.2 Trailer 56 4.4 Hydrogen utilization 56 4.4.1 Thermochemical utilization 56 4.4.2 Electrochemical utilization 59 4.5 Investigated energy conversion processes 69 5 Model Description 72 5.1 Components 72 5.1.1 Electrochemical cells 72 5.1.2 Rectifier and inverter 77 5.1.3 Metal hydride storage 78 5.1.4 Liquid hydrogen storage 78 5.1.5 Chemical reactors 78 5.1.6 Catalytic burner 81 5.1.7 Blower 81 5.1.8 Compressor 82 5.1.9 Turbine 82 5.1.10 Electrical engine and generator 82 5.1.11 Heat exchanger 83 5.1.12 Mixer and splitter 84 5.1.13 Sources and sinks 85 5.2 Combined cycle gas turbine 85 5.3 Electricity grid 85 5.4 The exergy method 85 5.5 Property data 88 5.6 Cost model 88 5.7 Load profiles 90 6 Process Analysis 92 6.1 Production 92 6.1.1 Alkaline electrolysis 92 6.1.2 Proton exchange membrane electrolysis 95 6.1.3 Solid oxide electrolysis 96 6.2 Storage 100 6.2.1 Methanation 100 6.2.2 Compression 101 6.2.3 Liquefaction 101 6.3 Transport 101 6.3.1 Gas grid 101 6.3.2 Trailer 101 6.4 Utilization 102 6.4.1 Combined cycle gas turbine 102 6.4.2 Proton exchange membrane fuel cell 104 6.4.3 Solid oxide fuel cell 109 7 Process Chain Analysis 118 7.1 Exergy Efficiency 118 7.1.1 Exergy analysis for full load operation 120 7.1.2 Exergy analysis for load following operation 124 7.2 Overall Costs 125 7.2.1 Cost analysis for full load operation 125 7.2.2 Cost analysis for load following operation 129 8 Waste exergy recovery overview 135 8.1 Waste heat exergy recovery 136 8.1.1 Solid oxide electrolysis 136 8.1.2 Clausius Rankine Cycles 137 8.1.3 Joule Cycles 138 8.1.4 Combination of Joule and Clausius Rankine cycles 139 8.2 Physical exergy recovery 140 8.3 Cryo-exergy recovery 140 9 Process Optimization 141 9.1 Physical exergy recovery 141 9.2 Waste heat exergy recovery 142 9.2.1 Solid oxide electrolysis 142 9.2.2 High Temperature PEM fuel cell 143 9.2.3 Solid oxide fuel cell 144 9.2.4 Reversible solid oxide cell system 149 10 Process Chain Optimization 154 10.1 Economic optimization 154 10.1.1 Costs for by-products 154 10.1.2 Application scenario 156 10.2 Comparison of optimized process designs in process chains 156 10.2.1 Physical exergy recovery 160 10.2.2 Heat exergy recovery 160 10.2.3 Combination of physical and heat exergy recovery 165 11 Conclusion 170 12 Outlook 174
Wasserstoff wird als einer der wichtigsten Energieträger zur Speicherung von fluktuierender Wind- und Solarenergie in einem nachhaltigen Energiesystem betrachtet. In dieser Arbeit werden Exergieeffizienz und Kostenanalysen durchgeführt, um verschiedene Pfade von Wasserstoffherstellung (PEM, alkalische oder Festoxidelektrolyse), -speicherung (Verdichtung, Verflüssigung oder Methanisierung), -transport (Trailer oder Pipeline) und -rückverstromung (PEM-, Festoxidbrennstoffzellen oder Gas- und Dampfkraftwerke (GuD)) zu vergleichen. Alle Prozessketten werden für Voll- und Teillast simuliert und ihrWirkungsgrad sowie die Kosten berechnet. Weiterhin werden Lastprofile abgeschätzt, um ein gesamtes Betriebsjahr unter schwankender Last zu simulieren. Die Ergebnisse zeigen exergetische Strom-zu-Strom-Wirkungsgrade von etwa 17.5 % bis 43 %. Die größten Verluste treten bei der Rückverstromung und bei der Herstellung von Wasserstoff auf. Methanisierung zeigt sowohl niedrigere Wirkungsgrade als auch höhere Kosten als Pfade mit reinem Wasserstoff. Während GuD-Kraftwerke sehr hohe Wirkungsgrade bei Volllast aufweisen, zeigen Brennstoffzellen im Lastfolgebetrieb über ein Gesamtjahr höhere Wirkungsgrade. Spezifische Gesamtkosten zwischen 245 e/MWh und 646 e/MWh werden durch die Simulation berechnet. Niedrigere Prozesskettengesamtkosten sind gemeinhin mit einem hohem Wirkungsgrad verbunden. Installationskosten sind auf Grund der niedrigen Volllaststundenzahl der hauptsächliche Treiber der Gesamtkosten. Um die Energiespeicherkosten der Prozessketten zu verringern, werden die Kostenreduktion durch den Verkauf von Nebenprodukten wie Sauerstoff und Wärme, sowie die Erweiterung der Anwendung untersucht. Während der Effekt des Erlöses durch den Verkauf von Sauerstoff gering ist, kann der von Wärme die Gesamtkosten signifikant verringern. Eine Erhöhung der Volllaststudenzahl durch das Einbeziehen einer Elektrolyse-Grundlast für die Bereitstellung von Wasserstoff für die mobile Anwendung zeigt auch eine deutliche Verringerung der Gesamtkosten auf bis zu 151 €/MWh bei 2337 h/a Volllaststunden. Die Optimierung des Wirkungsgrades wird durch die Analyse von physischer sowie Wärmeexergierückgewinnung durchgeführt. Dafür wird die Nutzung von Expansionsmaschinen im Gasnetz, der Einsatz von zusätzlichen Joule- und Clausius-Rankine-Prozessen, wie auch die Bereitstellung von Wärme für die Dampfelektrolyse aus der Methanisierung, der Kühlung zwischen Verdichtungsstufen und der Speicherung von Wärme analysiert. Die Berechnung zeigt, dass bei Volllast Prozessketten, die Wasserstoff mit Hilfe von Festoxidelektrolyse herstellen und diesen dann in einem GuD-Kraftwerk oder einer Festoxidbrennstoffzelle mit Clausius-Rankine- Prozess rückverstromen, exergetischeWirkungsgrade von 47 % bzw. 45.5 % erreicht werden können. Eine reversible Festoxidbrennstoffzelle, die Wärme und Wasserstoff in einem Metallhydrid speichert, kann exergetische Wirkungsgrade von 46.5 % erreichen. Die Energiespeicherkosten für diese Systeme können bei Volllast 35 bis 40 €/MWh betragen. Es kann angenommen werden, dass über ein Betriebsjahr der Wirkungsgrad steigen wird.:1 Introduction 22 2 Objective and Structure 24 3 Hydrogen as an Energy Vector 25 3.1 Mobile application focus 25 3.2 Stationary application focus 28 3.3 Studies on energy systems 32 3.4 Conclusion 36 4 Hydrogen Technology Overview 37 4.1 Hydrogen production 37 4.1.1 Electro-chemical hydrogen production 37 4.1.2 Thermo-chemical hydrogen production 42 4.1.3 Biological hydrogen production 46 4.1.4 Other hydrogen production processes 46 4.1.5 Gas cleaning 47 4.2 Hydrogen storage 49 4.2.1 Chemical compounds 49 4.2.2 Metal hydride 50 4.2.3 Physical storage 52 4.3 Hydrogen transport 54 4.3.1 Gas grid 54 4.3.2 Trailer 56 4.4 Hydrogen utilization 56 4.4.1 Thermochemical utilization 56 4.4.2 Electrochemical utilization 59 4.5 Investigated energy conversion processes 69 5 Model Description 72 5.1 Components 72 5.1.1 Electrochemical cells 72 5.1.2 Rectifier and inverter 77 5.1.3 Metal hydride storage 78 5.1.4 Liquid hydrogen storage 78 5.1.5 Chemical reactors 78 5.1.6 Catalytic burner 81 5.1.7 Blower 81 5.1.8 Compressor 82 5.1.9 Turbine 82 5.1.10 Electrical engine and generator 82 5.1.11 Heat exchanger 83 5.1.12 Mixer and splitter 84 5.1.13 Sources and sinks 85 5.2 Combined cycle gas turbine 85 5.3 Electricity grid 85 5.4 The exergy method 85 5.5 Property data 88 5.6 Cost model 88 5.7 Load profiles 90 6 Process Analysis 92 6.1 Production 92 6.1.1 Alkaline electrolysis 92 6.1.2 Proton exchange membrane electrolysis 95 6.1.3 Solid oxide electrolysis 96 6.2 Storage 100 6.2.1 Methanation 100 6.2.2 Compression 101 6.2.3 Liquefaction 101 6.3 Transport 101 6.3.1 Gas grid 101 6.3.2 Trailer 101 6.4 Utilization 102 6.4.1 Combined cycle gas turbine 102 6.4.2 Proton exchange membrane fuel cell 104 6.4.3 Solid oxide fuel cell 109 7 Process Chain Analysis 118 7.1 Exergy Efficiency 118 7.1.1 Exergy analysis for full load operation 120 7.1.2 Exergy analysis for load following operation 124 7.2 Overall Costs 125 7.2.1 Cost analysis for full load operation 125 7.2.2 Cost analysis for load following operation 129 8 Waste exergy recovery overview 135 8.1 Waste heat exergy recovery 136 8.1.1 Solid oxide electrolysis 136 8.1.2 Clausius Rankine Cycles 137 8.1.3 Joule Cycles 138 8.1.4 Combination of Joule and Clausius Rankine cycles 139 8.2 Physical exergy recovery 140 8.3 Cryo-exergy recovery 140 9 Process Optimization 141 9.1 Physical exergy recovery 141 9.2 Waste heat exergy recovery 142 9.2.1 Solid oxide electrolysis 142 9.2.2 High Temperature PEM fuel cell 143 9.2.3 Solid oxide fuel cell 144 9.2.4 Reversible solid oxide cell system 149 10 Process Chain Optimization 154 10.1 Economic optimization 154 10.1.1 Costs for by-products 154 10.1.2 Application scenario 156 10.2 Comparison of optimized process designs in process chains 156 10.2.1 Physical exergy recovery 160 10.2.2 Heat exergy recovery 160 10.2.3 Combination of physical and heat exergy recovery 165 11 Conclusion 170 12 Outlook 174

碩士
大同大學
機械工程研究所
89
PART ONE :The Study of Total Operational Cost with Different Fuel Prices in the Cogeneration System The thesis deals with cogeneration system of extraction-type steam turbine generator. Under taking into account of operational cost and enthalpy for fuel, it is an interesting place that how the cost is obtained as minimum by mixing coal and oil while cogeneration system is running. Based on the real design and industrial application, the attempt of the investment is to find the I/O curve for boiler and steam turbine from output data. Furthermore, it is possible to determine the optimum values from boiler and electric power with the lowest cost for fuel, water feeding, and benefits of selling power to Taiwan Power Company. The results show that the best way to save the operational cost is to generate and sell power from the extra steam with high loading at off-peak time while the price for coal is down to 1.7 NT$/kg. Instead, while oil price is up to 4.1 NT$/kg, the optimum value of steam generation can be determined as system is mid-loading. Consequently, it is not worthy to generate and sell the extra power to Taiwan Power Company when the cost of gas is up to 9 NT$/kg in low loading. Meanwhile, in addition, GateCycle 5.2 software is used for analyzing efficiency of whole system. And the output data can be applied as reference. PART TWO : The Exergy Analysis of Air-Conditioner without Condensed Water This part of thesis focuses on the air-conditioner without condensed water. In order to save power energy, the exergy loss of air-conditioner must be reduced. Meanwhile, how to deal with the condensed water is also a puzzle. Numerous attempts have been made by scholars for many years. However, extracted water jet tool, the instrument designed for solving these problems, has never been tried. This equipment utilizes theorem of water evaporation to save energy. First, this mechanism sucks condensed water from the base of evaporator by screw liked channel, and then water is spayed out all over the hot condenser. As a result of high temperature makes the water evaporate and take the heat away. Thus, more heat can be removed; the higher EER and COP values are obtained. As expected, the exergy is also decreased. Another more efficient approach suggested in this paper is to increase the speed of rotation for fans. Experiment shows that high speed of air to condenser can also save the exergy. Finally, both of the two efficient ways will be performed in Tables and proved later.

Hydrogen is a by-product of the gasification process and it is environmentally friendly with respect to pollution and emission issues when it is derived from a CO2-neutral resource such as biomass. It is an energy carrier fuel and has flexibility to convert efficiently to other energy forms to be used in different energy applications like fuel cells. The proposed research presents literature on previous gasification studies regarding hydrogen production from biomass and updates the obtained results. The main objectives of the thesis are: a) to study hydrogen production via steam biomass (sawdust) gasification; b) to evaluate the produced hydrogen by performing comprehensive analysis by using thermodynamic, exergoeconomic and optimization analyses. Despite details specific to the gasifier, in general, there is a special need to theoretically address the gasifier that gasifies biomass to produce hydrogen. This further study of gasification aspects presents a comprehensive performance assessment through energy and exergy analyses, provides results of the optimization studies on minimizing hydrogen production costs, and provides a thermo-economic analysis for the proposed systems (Systems I, II and III). This thesis also includes the results from the performed study that aims to investigate theoretical hydrogen production from biomass (sawdust) via gasification technology. Results from the performed parametric study show that the gasification ratio increases from 70 to 107 gH2 per kg of sawdust. In the gasification temperature studied, system II has the highest energy efficiency that considers electricity production where it increases from 72 % to 82 % and has the lowest energy efficiency that considers hydrogen yield where it increases from 45 % to 55 %. Also, it has the lowest hydrogen cost of 0.103 $/kW-h. The optimization results show that the optimum gasification temperatures for System I, System II and System III are 1139 K, 1245 K and 1205 K, respectively.
UOIT

ITALIANO - La valutazione energetica di un edificio ha lo scopo di quantificare le risorse energetiche impegnate dall’edificio per alimentare i fabbisogni delle utenze, in rapporto a criteri di natura energetica/ambientale/economica. I criteri di valutazione attualmente impiegati sono: energia primaria, emissioni di CO2, costi, energia finale. L’uso di energia a livello di edificio è messo in relazione rispettivamente con le risorse energetiche primarie impegnate, con le emissioni di gas a effetto serra e con gli oneri gestionali. In una visione centrata sulla combinazione tra catena energetica dalle sorgenti all’edificio e edificio, l’impiego di questi criteri è funzionale al raggiungimento di obiettivi strategici di vasta scala verso cui il settore degli edifici è chiamato a convergere. In una visione centrata sull’edificio, l’impiego di questi criteri implica tuttavia che il risultato della valutazione sia dipendente da parametri estrinseci: le infrastrutture energetiche e il mercato dell’energia, interpretati come fattori di conversione, fattori di emissione, tariffe, secondo cui sono differenziati vettori e fonti. Una lettura estesa dell’uso di energia a livello di edificio dovrebbe prendere in considerazione sia gli aspetti di primo principio (conservazione dell’energia), che gli aspetti di secondo principio (degradazione dell’energia). Al fine di delineare un criterio di valutazione energetica del sistema edificio che sia in grado di differenziare vettori e fonti secondo il relativo potenziale termodinamico e che risulti indipendente da parametri estrinseci, abbiamo individuato come strumento l’exergia. Il criterio exergetico delineato quantifica l’exergia impiegata dall’edificio per alimentare gli usi delle utenze in base all’exergia dei vettori di rete e delle fonti rinnovabili on-site utilizzate. In una visione centrata sull’edificio l’exergia dei vettori e delle fonti è determinata in corrispondenza del confine del sistema. La prestazione exergetica “Exergy Performance” è valutata come il quantitativo netto di exergia da vettori di rete e da fonti rinnovabili on-site impiegato dall’edificio per alimentare gli usi delle utenze ed è espressa attraverso un indice “ExP” normalizzato rispetto a un anno di attività e a una unità di superficie. Data l’assunzione di una visione centrata sull’edificio, il criterio exergetico è da mettere in relazione con gli usi finali dell’energia, in quanto svincolato dall’assetto delle infrastrutture energetiche. Il criterio exergetico costituisce uno strumento di valutazione energetica del sistema edificio in grado di incidere sull’assetto degli usi finali dell’energia nel settore degli edifici. All’aspetto di stabilità della valutazione si combina l’aspetto di indirizzo delle scelte energetiche e di interazione con le strategie di decarbonizzazione quali il fuel-switching da combustibili fossili a vettore elettrico e l’incentivazione di vettori localmente zero-carbon. Il criterio exergetico risulta in linea con gli scenari descritti in Energy Roadmap 2050 nella misura in cui la sua applicazione porta verso l’efficienza degli usi finali dell’energia, verso l’elettrificazione e verso l’aumento della quota di consumo finale lordo di energia alimentato tramite fonte rinnovabili. ENGLISH - The aim of the building energy assessment is to quantify the energy sources used from a building to satisfy the users needs, through the application of energy or environmental or economic methods. The assessment methods currently applied are: primary energy, CO2 emissions, costs, final energy. The building energy demand is related respectively with the primary energy sources consumption, the greenhouse gases emissions, the running costs. From a point of view centered on the connection between the building and the energy supply chain, these methods are suitable in order to reach overall energy-environmental targets imposed on the building sector. From a building-centered point of view, these methods imply that the assessment results are dependent from parameters external to the system: the primary energy factors, the emissions factors, the economic rate. The energy sources and the energy carriers are diversified according to these parameters. These parameters are representative of the energy supply chain and the energy market. An overall building energy assessment should take in account both the First Principle features (energy conservation) and the Second Principle features (energy degradation). In order to define a building energy assessment method that is able to diversify the energy sources and the energy carriers according to the respective thermodynamic potential, and that is indipendent from parameters external to the system, we have identified the exergy as useful concept. The exergy method developed quantifies the exergy used from a building to satisfy the users needs, both from grid energy carriers and on-site energy sources. Assuming a building-centered point of view, the exergy of energy carriers and energy sources is determined on the system boundary. The "Exergy Performance" is defined as the net sum of exergy, both from grid energy carriers and on-site energy sources, used from a building to satisfy the users needs. It is expressed by an index "ExP" normalized with respect to one year of building running and one square meter of building floor. Assuming a building-centered point of view, the exergy method must be related to the energy end-uses, because it is indipendent from the energy supply chain and the energy market. The exergy method is able to address the choices about the energy end-uses structure in the building sector. Besides enabling a stable building energy assessment, the exergy method is converging towards the decarbonisation strategies as the fuel-switching from fossil fuels to electricity and the facilitation of locally low-carbon energy carriers. The exergy method is in compliance with the energy scenarios described in Energy Roadmap 2050, because its application lead to the energy end-uses efficiency, the electrification and the increase of gross final energy consumption fuelled from renewable energy sources.

Economic assessment of power plants is one of the most critical steps before starting the project. Nowadays, investors and governments are looking for energy systems with lower investment costs leading to a shorter payback period. In the present research, economic and exergo-economic analysis of geothermal power plants has been conducted. This study has been divided into four different sections, (I) geothermal well drilling cost model generation, (II) power plant's equipment cost model generation, (III) entire geothermal power plants' economic model generation, and (IV) exergo-economic analysis of three geothermal case studies based on previous sections. QUE$TOR software is applied to calculate the costs of well drilling and power plant equipment, which is a robust and reliable cost estimator tool for well drilling and equipment costs, including a comprehensive cost database. Curve fitting and different optimization approaches have been applied in the models' generation process to reduce the deviations and calibration of obtained coefficients. The well drilling cost models are generated for different regions and countries based on the well number and depth. Also, the power plant's equipment cost models are proposed for the pump, heat exchangers, compressor, air-cooled condenser, and pressure vessel. Generated cost models are the most updated correlations based on the 2020 database. The generated equipment models are implemented in the entire power plants’ economic models generation. Considered models are the total cost rate, plant’s total cost, and power generation cost. The evaluated geothermal configurations are simple Organic Rankine Cycle (ORC), regenerative ORC, single flash, double flash, and flash-binary cycles. The proposed cost models in all sections are compared with other references, and it shows good compatibility with available literature. In the last part of this study, based on the generated well drilling and equipment cost models, exergy and exergo-economic assessment of three different geothermal case studies are performed. The first case is the Kizildere geothermal power plant (in Turkey), a triple-flash cycle coupled with an ORC unit. The second case is the Castelnuovo geothermal power cycle planned to construct in the Tuscany region, Italy. It is composed of an ORC cycle with a district heating system and total reinjection of non-condensable gases. And the last case is a improved scheme of Castelnuovo cycle with adding LiBr-H2O absorption chiller and Polymer Electrolyte Membrane (PEM) electrolyzer to generate more products.