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

Biomass-fired combined heating, cooling, and power for small scale applications – A review

The growing demand for energy and the accelerating threats from climate change call for innovative and sustainable solutions to decrease dependency on fossil fuels. Biomass -based, small-scale Combined Cooling, Heating and Power (CCHP) systems are one of these solutions, because they can satisfy the energy demands of the consumer with enhanced flexibility, l ower losses, less costs and less environmental pollution as compared to centralized facilities. Due to recent advances in several scientific subfields with relevance to small-scale CCHP, a rapidly increasing amount of literature is now available. Therefore, a structural overview is essential for engineers and researchers. This paper presents a review of the current investigations in small-scale CCHP systems covering biomass-fired concepts and solar extensions. To this end, critical system components are described and analysed according to their specific advantages and drawbacks. Recent case studies have been collected and key findings are highlighted according to each type of prime mover. The results indicate a scientific bias towards the economic viability of such systems and the need for real-life and experiment system data. However, the potential of biomass-fired CCHP systems and of such systems with solar extensions has clearly been recognised. Based on the results, future policy implementations should focus on fostering such systems in areas with high energy costs and to increase energy resilience in developed regions. Additionally research and industry applying novel prime mover technologies should be financially supported.Postprint (author's final draft

Efficacy of different strategies using an ALS-inhibitor herbicide for weed control in sugar beet (Beta vulgaris L.)

In den Jahren 2013 und 2014 wurden in sechs Umwelten in Deutschland Feldversuche durchgeführt, um die Wirksamkeit eines neuen ALS-Inhibitor Herbizids (F/T) zur Unkrautkontrolle im Zuckerrübenanbau zu bewerten. Fünf Herbizidstrategien mit verschiedenen Anwendungen von F/T (50 g Foramsulfuron ha–1 + 30 g Thiencarbazone-methyl ha–1) und eine klassische Herbizidstrategie mit drei Applikationen von Phenmedipham (75 g Wirkstoff ha–1), Desmedipham (59 g Wirkstoff ha–1), Ethofumesat (94 g Wirkstoff ha–1), Lenacil (34 g Wirkstoff ha–1) und Metamitron (700 g Wirkstoff ha–1) wurden miteinander verglichen. Die Wirksamkeit der klassischen Herbizidstrategie lag zwischen 84 und 99% durch nicht voll­ständig kontrollierte Chenopodium album L., Matricaria recutita L., Mercurialis annua L. und Solanum tuberosum L. Die durchschnittliche Wirksamkeit von F/T lag bei 95% in der einmaligen Applikation. Strategien mit zwei Applikationen in Kombination von klassischen Herbiziden und F/T erreichten eine Wirksamkeit über 97%. Dies führt zu einer höheren Flexibilität der Unkrautkontrolle in Zuckerrüben.In 2013 and 2014, field trials were conducted at six environments in Germany to evaluate the efficacy of a new ALS-inhibiting herbicide containing foramsulfuron and thiencarbazone-methyl (F/T) for weed control in sugar beet cultivation. Five herbicide strategies with different application frequencies of F/T (50 g foramsulfuron ha–1 + 30 g thiencarbazone-methyl ha–1) and a classic herbicide strategy with three applications of phenmedipham (75 g ai ha–1), desmedipham (59 g ai ha–1), ethofumesate (94 g ai ha–1), lenacil (34 g ai ha–1) and metamitron (700 g ai ha–1) were compared. The efficacy of the classic herbicide strategy was between 84 and 99% due to surviving Chenopodium album L., Matricaria recutita L., Mercurialis annua L. and Solanum tuberosum L. Average efficacy of F/T was 95% in the single application treatment. Strategies with two applications combining classic herbicides and F/T achieved an efficacy beyond 97%. This points to an increased flexibility of weed control in sugar beet

How to transform European housing into healthy and sustainable living spaces using a Belgian case study? – the RenovActive principles tackle climate and renovation challenges

The RenovActive renovation concept seeks to offer healthy, affordable, easy to reproduce, scalable solutions for the existing building stock of European housing. The concept was developed and tested in a prototype phase, where 7 principles have been applied to a semidetached house built in the 1920s, situated in a garden city in Brussels. The renovated prototype was occupied by a family and monitored for two years. The monitoring was performed, after renovation, both through data, sensors, and extensive interviews and questionnaires with the family. In general, the family living in the house is very satisfied with the indoor environment. The results show a general indoor CO2- concentration below 900 ppm, and an indoor temperature between 21°C and 26°C. The technical and sociological monitoring show indication for the additional potential to optimize and improve indoor comfort levels and perception. As an example, there are discrepancies between setpoints and programming we initiated, based on standards and scientific inputs, based on predicted behaviors. But user interactions, and preferences in real life situation when occupying the house, as well as situational perceptions and culture, modified user setpoints compared to our initial setpoints, that in some settings could have a negative impact on the indoor environment. This indicates that a technical system operating the indoor environment must be both flexible and robust to accommodate for multiple and varying preferences of building inhabitants.publishedVersio