Island-based polygeneration systems : feasibility of bBiomass-driven distributed concepts

The colossal risks and challenges posed by climate change require innovative solutions that must fulfil energy service demands sustainably. The concept of small-scale, biomass-based polygeneration (SBP) is one such technological approach, which optimizes locally supplied fuels to provide several energy services like electricity, heating, cooling, potable water, and/or bio-chemical products. By presenting chosen SBP systems and models employed in various socio-geographic locations, in particular distributed applications, the thesis identifies benefits as well as drawbacks of the SBP concept and aims to promote its wider usage in the field. Because a multitude of technologies can be applied for polygeneration system design, the thesis starts with a thorough review of the highly complex and rapidly evolving field, where relevant literature is presented and assimilated. Based on this review, several models have been created for various solar-assisted SBP systems: Firstly, a small-scale Combined Cooling, Heating, and Power (CCHP) system based on biomass gasification has been investigated for a hotel resort on one of the Andaman Islands, India. Apart from economic and environmental superiority compared to a fossil-fuel reference system, the study also expanded technological aspects by adding a socio-political analysis of the benefits and drawbacks of the system for the entire island community. In the second study, a novel control algorithm was devised for a biogas-based polygeneration system generating electricity and potable water generation for a rural off-grid village in El Pando, Bolivia. It was found that the proposed system could lead to significant cost and emissions reductions paired with greater energy autonomy. In the third study, an optimization model for a combined gasification-based CCHP/Heat Pump (HP) system is presented for a tourist facility in Barcelona considering various climate scenarios. The study reveals that the system design is only slightly affected by future changes in climate and that the CCHP/HP system shows only a moderate economic performance but still considerable CO2-savings potential. The overall findings of these studies reveal that the economic feasibility of SBP systems depends greatly not just on their inherent design but also on their location. However, all proposed polygeneration systems could lower emissions significantly, while excelling in energy efficiency as well as adaptability towards service demands and other technologies. The presented studies contribute to the state of the art by adding innovative polygeneration system designs, proposing new modelling approaches and subsequent models including SBP system enhancing technologies, as well as by investigating the effects of geographical location and climate change on the system design process.Los colosales riesgos y retos puestos por el cambio climático requieren soluciones creativas para satisfacer las demandas de servicios energéticos de una manera más sostenible, comparado con los sistemas actuales. El concepto de poligeneración a escala pequeña y basada en biomasa (Small-scale, biomass-based polygeneration o SBP) es uno de estos enfoques, que optimiza el uso de combustible locales para proveer varios servicios energéticos como electricidad, calor, enfriamiento, agua potable y/o productos bioquímicos. Presentando una selección de sistemas SBP y modelos empleados en varias localizaciones socio-geográficas, esta tesis identifica los beneficios e inconvenientes del concepto SBP con el objetivo de promover su un uso más amplio en el mundo. Como se puede aplicar una multitud de tecnologías para el diseño de sistemas SBP, la tesis empieza con una revisión profunda del campo, altamente complejo y dinámico, donde la literatura relevante está presentada en una forma estructurada y resumida. Basado en esta revisión, se han creado varios modelos SBP para varios sistemas SBP con asistencia solar: Principalmente, se ha investigado un sistema de generación conjunta de frio, calor y electricidad (en inglés: Combined Cooling, Heating, and Power or CCHP) basado en gasificación de biomasa para un resort (hotelero) en una de las islas Andamán, India. Además de mostrar de una superioridad económica y ambiental comparado con el sistema de referencia de combustibles fósiles, el estudio expandió el conocimiento científico añadiendo un análisis socio-político de los beneficios e inconvenientes del sistema SBP para la comunidad de la isla entera. En el segundo estudio, se ha desarrollado un nuevo algoritmo de control para un sistema de poligeneración basado en biogás, que genera electricidad y agua potable para una comunidad rural y sin conexión a una red eléctrica más grande en el Pando, Bolivia. Se ha revelado que el sistema propuesto podría bajar significantemente los costes y las emisiones junto con un aumento de la autonomía energética. En el tercer estudio se ha presentado un modelo de optimización para un sistema combinado de CCHP y bombas de calor (sistema CCHP/HP), que se considera para una estructura museístico-turística en Barcelona y para varios escenarios climáticos. En el estudio se ha descubierto que el cambio climático influye sólo ligeramente en el diseño del sistema óptimo, y que el sistema CCHP/HP demuestra sólo un moderado desempeño económico, similar al convencional, pero también un potencial considerable para la reducción de emisiones de CO2. El conjunto de los estudios revela que la viabilidad económica de los sistemas SBP depende altamente no solo de su diseño inherente, sino también de su entorno. De todos modos, todos los sistemas SBP propuestos podrían bajar las emisiones significantemente, mientras sobresalen en eficiencia energética y adaptabilidad a servicios energéticos y tecnologías alternativas. Los estudios presentados contribuyen al estado del arte añadiendo diseños innovadores de sistemas SBP, proponiendo nuevos enfoques de modelado y cálculo, y subsecuentemente nuevos modelos incluyendo tecnologías aumentando sistemas SBP, e investigando los efectos de la ubicación geográfica y del cambio climático al proceso del diseño de los sistemas SBP.Sammanfattning Klimatförändringen bär med sig kolossala risker och utmaningar, som kräver innovativa lösningar för att tillhandahålla energitjänster på ett mer hållbart sätt än med tidigare energisystem. Konceptet med småskaliga, biomassa-baserade polygeneration (SBP) system är ett sådant teknologiskt tillvägagångssätt, vilket optimerar användningen av lokalt producerat bränsle för att tillhandahålla olika energitjänster som elektricitet, värma, kyla, dricksvatten, eller/och bio-kemiska produkter. Doktorsarbetet identifierar för- och nackdelar hos olika SBP konceptet genom att presentera ett urval av SBP system och modeller av dem för olika geografiska regioner, med mål att främja vidare applikation av dem i fält. Eftersom en mängd tekniker kan användas för design av polygenerationssystem, börjar avhandlingen med en grundlig genomgång av det mycket komplexa och snabbt utvecklande området, där relevant litteratur presenteras och assimileras. Baserat på denna recension har flera modeller skapats för olika solassisterade SBP-system: För det första har ett småskaligt kombinerat kyl-, värme- och kraftsystem (CCHP) baserat på biomassaförgasning undersökts för en hotellanläggning på en av Andamanöarna, Indien. Bortsett från ekonomisk och miljömässig överlägsenhet jämfört med ett referenssystem för fossila bränslen har studien även inkluderat tekniska aspekter genom att lägga till en socio-politisk analys av fördelarna och nackdelarna med systemet för hela ö-samhället. I den andra studien utvecklades en ny regleralgoritm för ett biogasbaserat polygenereringssystem som genererar el och renar vatten till dricksvatten för en by utan elförsörjning i El Pando, Bolivia. Det konstaterades att det föreslagna systemet kan leda till betydande kostnads- och utsläppsminskningar i kombination med större energiautonomi. I den tredje studien presenteras en optimeringsmodell för ett kombinerat förgasningsbaserat CCHP / värmepumpsystem (HP) för en turistanläggning i Barcelona under olika klimatscenarier. Studien avslöjar att systemdesignen bara i låg grad påverkas av framtida klimatförändringar och att CCHP / HP-systemet endast visar en måttlig ekonomisk prestanda men fortfarande en betydande potential för CO2-besparingar. De övergripande resultaten av dessa studier visar att den ekonomiska genomförbarheten för SBP-system inte bara beror på deras inneboende design utan också på deras lokalisering. Alla föreslagna SBP-system kan emellertid sänka emissionerna betydligt, samtidigt som de sticker ut i energieffektivitet samt anpassningsbarhet efter energitjänster och annan teknik. De presenterade studierna bidrar till vetenskapen genom att lägga till innovativa SBP-systemdesigner, föreslå nya modelleringsmetoder och efterföljande modeller inklusive SBP-systemförbättrande teknik, samt genom att undersöka effekterna av geografisk plats och klimatförändringar på systemdesignprocessenErasmus Mundus en serveis energètics sostenible

Geothermal Energy Utilization and Technologies 2020

Rising pollution, climate change and the depletion of fossil fuels are leading many countries to focus on renewable-based energy conversion systems. In particular, recently introduced energy policies are giving high priority to increasing the use of renewable energy sources, the improvement of energy systems’ security, the minimization of greenhouse gas effect, and social and economic cohesion. Renewable energies’ availability varies during the day and the seasons and so their use must be accurately predicted in conjunction with the management strategies based on load shifting and energy storage. Thus, in order to reduce the criticalities of this uncertainty, the exploitation of more flexible and stable renewable energies, such as the geothermal one, is necessary. Geothermal energy is an abundant renewable source with significant potential in direct use applications, such as in district heating systems, in indirect use ones to produce electricity, and in cogeneration and polygeneration systems for the combined production of power, heating, and cooling energy. This Special Issue includes geothermal energy utilization and the technologies used for its exploitation considering both the direct and indirect use applications

Investigation of a novel solar photovoltaic/loop-heat-pipe heat pump system

With the widespread deployment of solar photovoltaic (PV) and thermal devices imminent, this research aims to resolve some engineering barriers to the existing solar photovoltaic/thermal (PV/T) technologies by incorporating an innovative loop heat pipe (LHP) and a typical heat pump. In addition, a coated aluminium-alloy (Al-alloy) sheet replaces the conventional baseboard for the PV cells to improve heat exportation. As a result, this research has developed a novel solar PV/LHP heat pump system to maximise the electrical output of a PV module and generate an additional amount of heat simultaneously.The overall investigation followed the basic methodology of combined theoretical and experimental analysis, including procedures for a critical literature review, optimal concept design, mathematical derivation, the development of simulation models, prototype fabrication, laboratory-controlled and field testing, simulation model validation and socio-economic analysis. A full range of specialised simulation models was developed to predict the system performance with reasonable accuracy. The proposed LHP device has a maximum heat transfer limit of about 900W. The Al-alloy baseboard improved PV efficiency by nearly 0.26% when compared with a traditional PV baseboard. During the real-time measurement conditions, the mean electrical, thermal and overall energetic/exergetic efficiencies of the PV/LHP module were 9.13%, 39.25% and 48.37%/15.02%, respectively. The basic thermal and advanced system coefficients of performance (COPth/COPPV/T) were almost 5.51 and 8.71, respectively. The test results indicated that this system performed better than conventional solar/air energy systems. The feasibility analysis illustrated that this system could generate a substantial amount of energy in subtropical climatic regions, such as Hong Kong. It is cost effective to operate this system in areas with high energy charging tariffs, such as London and Hong Kong.The research results are expected to configure feasible solutions for future PV/T technologies and develop a new solar-driven heating system. The core technologies may enable a significant reduction in or even elimination of the carbon footprint in the built environment

Energy Systems and Applications in Agriculture

Agriculture, as a production-oriented sector, entails energy as a substantial input by which global food security is ensured. Agricultural systems require energy for farm machinery and equipment; lighting; heating, ventilation, and air-conditioning (HVAC); food processing and preservation; fertilizer and chemical production; and water/wastewater treatment/application. Increasing agriculture mechanization mitigates conventional energy reserves that escalate greenhouse gas emissions and climate change.This book aims to offer energy-efficient and/or environment-friendly ways for the agriculture sector to achieve the 2030 UN Sustainable Development Goals. The book provides cutting-edge research on next-generation agricultural technologies and applications to develop a sustainable solution for modern greenhouses, temperature/humidity control in agriculture, farm storage and drying, crop water requirements, agricultural built environment, and wastewater treatment

ECOS 2012

The 8-volume set contains the Proceedings of the 25th ECOS 2012 International Conference, Perugia, Italy, June 26th to June 29th, 2012. ECOS is an acronym for Efficiency, Cost, Optimization and Simulation (of energy conversion systems and processes), summarizing the topics covered in ECOS: Thermodynamics, Heat and Mass Transfer, Exergy and Second Law Analysis, Process Integration and Heat Exchanger Networks, Fluid Dynamics and Power Plant Components, Fuel Cells, Simulation of Energy Conversion Systems, Renewable Energies, Thermo-Economic Analysis and Optimisation, Combustion, Chemical Reactors, Carbon Capture and Sequestration, Building/Urban/Complex Energy Systems, Water Desalination and Use of Water Resources, Energy Systems- Environmental and Sustainability Issues, System Operation/ Control/Diagnosis and Prognosis, Industrial Ecology

Sustainable energy for a resilient future: proceedings of the 14th International Conference on Sustainable Energy Technologies

Volume I, 898 pages, ISBN 9780853583134 Energy Technologies & Renewables Session 1: Biofuels & Biomass Session 5: Building Energy Systems Session 9: Low-carbon/ Low-energy Technologies Session 13: Biomass Systems Session 16: Solar Energy Session 17: Biomass & Biofuels Session 20: Solar Energy Session 21: Solar Energy Session 22: Solar Energy Session 25: Building Energy Technologies Session 26: Solar Energy Session 29: Low-carbon/ Low-energy Technologies Session 32: Heat Pumps Session 33: Low-carbon/ Low-energy Technologies Session 36: Low-carbon/ Low-energy Technologies Poster Session A Poster Session B Poster Session C Poster Session E Volume II, 644 pages, ISBN 9780853583141 Energy Storage & Conversion Session 2: Heating and Cooling Systems Session 6: Heating and Cooling Systems Session 10: Ventilation and Air Conditioning Session 14: Smart and Responsive Buildings Session 18: Phase Change Materials Session 23: Smart and Responsive Buildings Session 30: Heating and Cooling System Session 34: Carbon Sequestration Poster Session A Poster Session C Poster Session D Policies & Management Session 4: Environmental Issues and the Public Session 8: Energy and Environment Security Session 12: Energy and Environment Policies Poster Session A Poster Session D Volume III, 642 pages, ISBN 9780853583158 Sustainable Cities & Environment Session 3: Sustainable and Resilient Cities Session 7: Energy Demand and Use Optimization Session 11: Energy Efficiency in Buildings Session 15: Green and Sustainable Buildings Session 19: Green Buildings and Materials Session 24: Energy Efficiency in Buildings Session 27: Energy Efficiency in Buildings Session 28: Energy Efficiency in Buildings Session 31: Energy Efficiency in Buildings Session 35: Energy Efficiency in Buildings Poster Session A Poster Session D Poster Session

Thermal analysis of combined Organic Rankine-Vapour compression system for heating and cooling applications

Climate change due to global warming is a matter of major global concern. Greenhouse gases emissions are a key culprit in this process. It is therefore important to reduce energy consumption in order to protect the environment. The decarbonisation of the heating sector would have a significant positive impact on the environment. A wide range of heating technologies have been investigated and developed, such as gas boilers, electric restrictive heaters, heat pumps (HP), and others. In order to reduce fossil fuel consumption and greenhouse gas emissions, researchers have focused on improving the performance of the existing technologies as well as on developing new fuel-efficient systems such as cogeneration and trigeneration cycles. These integrated technologies allow the production of multi-mode energies including heating, cooling, and/or mechanical power from the same primary energy source. The energy source can be a fossil fuel, or renewable energy such as solar, geothermal, biomass or wasted heat. Waste heat utilization (from a data centre, internal combustion engine, chamber exhaust stream, etc.) also has the potential of enhancing the system performance by reducing fuel consumption. In this thesis, an innovative gas fuelled heating system based on a combined heat engine and its reverse heat pump cycle is proposed and investigated. This system consists of a gas burner, an organic Rankine cycle power generator, and an air source heat pump vapour compression cycle. For the theoretical analysis, in-house MATLAB code is developed, and the steady state results are compared with the results acquired from ASPEN PLUS as a benchmark. Both software programs use REFPROP as the database for working fluid thermophysical properties. In order to identify a suitable working fluid for each cycle, a comparative study on various working fluids was initially carried out. The selection of refrigerant was based on performance and environmental safety profile. The proposed cycle is designed for domestic hot water supply and utilizes gas burner flue gases and ambient air to enhance the system overall fuel to heat efficiency while maintaining the heat pump cycle in a frost free state at low ambient temperature. The combined cycle shows promising performance, with a fuel to heat efficiency of 136%. However, the results also show that ambient air temperature fluctuations can have a significant impact on the combined system’s performance. To tackle this, various control strategies are proposed and investigated. Also, a dynamic model has been built using ASPEN PLUS software to simulate and validate the control strategy

New Trends in Enhanced, Hybrid and Integrated Geothermal Systems

Geothermal energy is a renewable, sustainable, and ecologically friendly resource of energy that can be captured with shallow or deep installations, or a combination of both—alone or integrated with other technologies. It can then be employed for a variety of purposes, for example, electricity generation, space heating and cooling, agriculture, and aquaculture. Given the nature/features of this green energy resource—such as being a local, climate-independent, potentially constant, robust, generally available, resilient, almost greenhouse gas-free, and long-lived energy source—geothermal solutions can and should make a more prominent contribution to the future global energy supply mix, in addition to helping lessen humanity’s environmental footprint and enabling it to attain its sustainable development goals. This Special Issue, “New Trends in Enhanced, Hybrid and Integrated Geothermal Systems”, addresses existing knowledge gaps and aids advance deployment of geothermal energy globally. It consists of eight peer-reviewed papers that cover a range of subjects and applications related to geothermal energy

Heat Transfer in Energy Conversion Systems

In recent years, the scientific community’s interest towards efficient energy conversion systems has significantly increased. One of the reasons is certainly related to the change in the temperature of the planet, which appears to have increased by 0.76 °C with respect to pre-industrial levels, according to the Intergovernmental Panel on Climate Change (IPCC), and this trend has not yet been stopped. The European Union considers it vital to prevent global warming from exceeding 2 °C with respect to pre-industrial levels, since this phenomenon has been proven to result in irreversible and potentially catastrophic changes. These climate changes are mainly caused by the emissions of greenhouse gasses related to human activities, and can be drastically reduced by employing energy systems, for both heating and cooling of buildings and for power production, characterized by high efficiency levels and/or based on renewable energy sources. This Special Issue, published in the journal Energies, includes 12 contributions from across the world, including a wide range of applications, such as HT-PEMFC, district heating systems, a thermoelectric generator for industrial waste, artificial ground freezing, nanofluids, and others