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The need for an improved control strategy for the operation of a wind-powered refrigeration system for the storage of apples was investigated. The results are applicable to other systems which employ intermittently available power sources, battery and thermal storage, and an auxiliary, direct current power supply. Tests were conducted on the wind-powered refrigeration system at the Virginia Polytechnic Institute and State University Horticulture Research Farm in Blacksburg, Virginia. Tests were conducted on the individual components of the system. In situ windmill performance were also conducted. The results of these tests have been presented. An improved control strategy was developed to improve the utilization of available wind energy and to reduce the need for electrical energy from an external source while maintaining an adequate apple storage environment. Ph. D.

Green ammonia is gaining momentum as a globally significant technology for deep decarbonisation. In this thesis, several models are developed across chemical, techno-economic, and energy system modelling disciplines to explore the future role of green ammonia. First, standalone models of production (i.e., power-to-ammonia) and re-electrification (i.e., ammonia-to-power) are developed and compared to competing technologies. Second, these models are integrated into a planning and dispatch energy system model (ESM) of India to 2050. The ESM has several novel additions including the sector coupling of hydrogen and ammonia, multiple years of granular weather data, and learning-curve-based technology cost forecasts. India is chosen as an ideal case study given its globally unmatched demand growth in all three relevant sectors: electricity, green hydrogen, and green ammonia. The projected electricity demands for green hydrogen and ammonia production account for 25% of the total Indian electricity demand in 2050, underscoring the transformational potential that green hydrogen and ammonia sector coupling can have on the Indian energy system. The results of the state-of-the-art ESM highlight synergistic effects of hydrogen and ammonia sector coupling with the power system. The least-cost system employs seasonal green ammonia production paired with up to 40 million tonnes (i.e., 200 TWh) of ammonia storage, as well as some re-electrification via gas turbines. Sector coupling reduces system curtailment, addresses challenges of long-duration storage, and improves system resilience to interannual weather variations. While India is a crucial case study from a global decarbonisation perspective, the methodology and findings are generally applicable, and it is the aim of this work to motivate and accelerate the wider research community into considering the potential impacts of green ammonia sector coupling on electricity grid design. Finally, this work highlights strategic technology development direction for ammonia producers and gas turbine manufacturers, as well as implications for policymakers.

The 2022 World Cup organised by the International Association Football Federation (International Olympic Committee, 2021) and hosted by Qatar was billed to be the tournament that would completely revolutionise football, both on and off the field. It garnered acclaim in being the first World Cup held outside its customary months of June-July as well as in pioneering net zero carbon emissions in the sport - an assertion that ultimately proved largely unfounded(Ralston, 2022) with high reputational consequences for the country and the game. Non-governmental organisations (NGOs), like the Carbon Market Watch that works with the European Union amongst others, claimed that “carbon emissions created by the new stadiums could be as much as eight times higher than the figures contained in Qatar’s analysis” (MacInnes, 2022). Against the backdrop of mounting sustainability concerns expressed by policymakers and enthusiasts alike, this essay examines the environmental hazards associated with major sporting events, like the 2022 FIFA World Cup whilst delving into adaptations that organisers could make for future sporting bonanzas that would give their green aspirations wings that could fly without getting burned like the fabled Icarus whose own pride and arrogance led him to ignore the rising temperatures and ultimately cause his demise. Essex Student Journal Volume 14 Issue S1 2023

Solar power appears to be one of the most promising resources to meet the medium and long term renewable energy targets. The integration of large amounts of photovoltaic (PV) generation into distribution networks faces some limitations due to the network constraints. The PV community became well aware of these limitations in the last years. While first solutions have been pointed out mainly for large installations connected to the medium voltage network, the specificities of low voltage networks are still not fully understood. This paper aims at explaining the challenges associated to the planning and operation of low voltage network with high PV penetration. The actual impact of PV infeed is quantified on the basis of real and accurate network, load and generation data. Results from unsymmetrical load-flow computations are presented and the implementation of reactive power-based voltage control is shortly discussed. 26th European Photovoltaic Solar Energy Conference and Exhibition; 4469-4478

In the pursuit of creating efficient CdTe p-n homojunctions, we developed iodine (I) n-type doped CdTe using Cadmium Iodide (CdI2) as a dopant in varying concentrations (1018 cm-3, 1019 cm-3 and 1020 atoms·cm-3 target concentrations) in CdTe. Iodide doped crystals were grown using a Modified Vertical Bridgman furnace (MVB). Single crystals were characterized using XRD (X-Ray Diffraction), Hall effect, IR (Infrared) Microscopy, UV-VIS-NIR (Ultraviolet-Visible-Near infrared Spectroscopy) and FTIR (Fourier Transform Infrared Spectroscopy). Partners at the National Renewable Energy Laboratory (NREL) also provided data for Hall Effect and Two Photon Excitation Time Resolved Photoluminescence (2PE TRPL) of wafers and films. Photoluminescence mapping (PL mapping) was obtained from Klar scientific, and glow discharge mass spectrometry (GDMS) for purity and final doping concentration was obtained from the National Research Council Canada. Due to poor carrier properties in the crystals as-grown, two annealing treatments were explored, in either tellurium or cadmium vapor. Homojunctions were made at NREL by depositing n-type films from these crystals on p-type single crystals, CdTe:P grown and WSU. The n-type films were created using the close-space sublimation epitaxy (CSSE) process. Herein is reported the results of the grown CdTe:I crystals and, to a lesser extent, the properties of the CdTe:I thin films formed by CSSE.

{"references": ["U.S. Energy Information Administration. \"How much energy is\nconsumed in residential and commercial buildings in the United States?\"\nAvailable at: http://www.eia.gov/tools/faqs/faq.cfm?id=86&t=1", "S. Darby, \"The effectiveness of feedback on energy consumption.\"\nEnvironmental Change Institute, University of Oxford, 2006. Available\nat: http://www.globalwarmingisreal.com/energyconsump-feedback.pdf.\nVisited: September 2015", "J. S. John, \"Putting energy disaggregation tech to the test,\" November,\n2013. Greentech Media. Available at:\nhttp://www.greentechmedia.com/articles/read/putting-energydisaggregation-tech-to-the-test.\nVisited: September 2015", "A. Zoha, A. Gluhak, M. A. Imran, S. Rajasegarar, \"Non-intrusive load\nmonitoring approaches for disaggregated energy sensing: a survey,\"\nSensors, vol. 12, no. 12, pp. 16838-16866, December 2012.", "G. W. Hart, \"Nonintrusive appliance load monitoring,\" in Proc. of the\nIEEE, vol. 80, pp. 1870-1891, December 1992.", "M. Baranski, J. Voss, \"Non-intrusive appliance load monitoring based\non Optical Sensor,\" IEEE Bologna PowerTech Conference, Bologna,\nItaly, June 2003. Available at:\nhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1304732", "L. Farinaccio, R. Zmeureanu, \"Using a pattern recognition approach to\ndisaggregate the total electricity consumption in a house into the major\nen-uses,\" Elsevier, Energy and Buildings, vol. 30, no. 3, pp. 245-259,\nAugust 1999.", "J. M. Abreu, F. C. Pereira, P. Ferr\u00e3o, \"Using pattern recognition to\nidentify habitual behavior in residential electricity consumption,\"\nElsevier, Energy and Buildings, vol. 49, pp. 479-487, June 2012.", "C. Beckel, L. Sadamori, S. Santini, \"Automatic socio-economic\nclassification of households using electricity consumption data,\" in\nProc. of the 4th international conference on future energy systems, New\nYork, 2013, pp. 75-86.\n[10] H. Zhao, F. Magoul\u00e8s, \"A review on the prediction of building energy\nconsumption,\" Elsevier, Renewable and Sustainable Energy Reviews,\nvol. 16, no. 6, pp. 3586-3592, August 2012.\n[11] G. K. F. Tso, K. K. W. Yau, \"Predicting electricity energy consumption:\nA comparison of regression analysis, decision tree and neural networks,\"\nElsevier, Energy, vol. 32, no. 9, pp. 1761-1768, September 2007.\n[12] F. Farzan, S. A. Vaghefi, K. Mahani, M. A. Jafari, J. Gong, \"Operational\nplanning for multi-building portfolio in an uncertain energy market,\"\nElsevier, Energy and Buildings, vol. 103, pp. 271-283, September 2015."]} Energy disaggregation has been focused by many energy companies since energy efficiency can be achieved when the breakdown of energy consumption is known. Companies have been investing in technologies to come up with software and/or hardware solutions that can provide this type of information to the consumer. On the other hand, not all people can afford to have these technologies. Therefore, in this paper, we present a methodology for breaking down the aggregate consumption and identifying the highdemanding end-uses profiles. These energy profiles will be used to build the forecast model for optimal control purpose. A facility with high cooling load is used as an illustrative case study to demonstrate the results of proposed methodology. We apply a high level energy disaggregation through a pattern recognition approach in order to extract the consumption profile of its rooftop packaged units (RTUs) and present a forecast model for the energy consumption.

I derive and test predictions from the classic Mussa and Rosen (1978) second-degree price discrimination model using data from the United States clothes washer market. I find evidence consistent with price discrimination in the market response to energy efficiency policy changes. Concurrent with the effective dates of both the new 2004 and 2007 federal minimum efficiency and ENERGY STAR standards, within-model clothes washer prices dropped on average. The heterogeneous pattern of price reduction across market segments, and adjustments in the menu of products, were consistent with predictions from the price-discrimination model, and not with a perfectly competitive market.

Ressourcen stellen die Basis für eine erfolgreiche industrielle und technologische Entwicklung dar und somit auch für den Wohlstand heutiger und zukünftiger Generationen. Mit steigender Ressourcennutzung nehmen auch die (physische und sozio-ökonomische) Verfügbarkeit abiotischer und biotischer Ressourcen, die Umweltverschmutzung und die sozialen Auswirkungen durch den Abbau und Nutzung der Ressourcen zu. Um den Erfolg implementierter Strategien (und deren Maßnahmen) hinsichtlich ihres Beitrags zu einem effizienten und nachhaltigen Umgang mit Ressourcen zu bewerten, bedarf es an entsprechenden Bewertungsmethoden. Diese Dissertation stellt vier Methoden bereit um die Bewertung abiotischer und biotischer Ressourcennutzung im Kontext der Nachhaltigkeit auf Produkt- und regionaler Ebene in konsistenter Weise zu bewerten. Die Methode zur Bewertung abiotischer Ressourcen auf Produktebene betrachtet insgesamt 21 relevante Aspekte und stellt Indikatoren zur Quantifizierung bereit. Für die Bewertung der sozio-ökonomischen Einschränkungen von Lieferketten ist eine neuer Ansatz entwickelt, der geopolitische, politische und regulative Aspekte berücksichtigt. Des Weiteren sind Screening-Indikatoren verfügbar, die die gesellschaftliche Akzeptanz der Ressourcennutzung adressieren. Um die Verfügbarkeit terrestrischer biotischer Ressourcen in Produktsystemen zu bewerten, wurde eine umfassende Methode mit 25 Indikatoren erstellt. Des Weiteren wird ein Ansatz vorgestellt, der es ermöglicht eine konsistente Zusammenführung und somit auch Bewertung verschiedener Ressourcentypen zu ermöglichen. Er findet bei der Zusammenführung der entwickelten Methoden zur Bewertung abiotischer und biotischer Ressourcen Anwendung. Da die Nutzung von Ressourcen auch auf Macro-Ebene betrachtet werden muss, wurde eine Methode zur Bewertung abiotischer Ressourcen auf regionaler Ebene entwickelt, die 25 Indikatoren für die Bewertung der Kritikalität (Verfügbarkeit von Ressourcen und Vulnerabilität der Region) und der gesellschaftlichen Akzeptanz zur Verfügung stellt. Verschiedene Fallstudien wurden durchgeführt um die Anwendbarkeit der entwickelten Methoden aufzuzeigen und zu verdeutlichen, warum eine umfassende Bewertung der Ressourcennutzung notwendig ist. Die Fallstudien umfassen u.a. die Bewertung eines Smartphones, Pkw-Herstellung und Biokraftstoffe. Die Anwendbarkeit der Methoden wird zudem erhöht, indem Indikatorwerte für 36 Metalle und 4 fossile Rohstoffe zur Verfügung gestellt werden. Die Bewertung der Nutzung abiotischer und biotischer Ressourcen auf Produkt- und regionaler Ebene wird mit dieser Dissertation signifikant verbessert, indem vier wissenschaftliche Methoden zur robusten und umfassenden Bewertung aller drei Nachhaltigkeitsdimensionen bereitgestellt werden. Resources are the basis for a thriving industrial and technological development and therefore for prosperity of present and future generations. With increasing resource use, challenges with regard to (physical and socio-economic) availability of abiotic and biotic resources and raw materials, pollution of the environment as well as social impacts associated with resource extraction and use arise. To evaluate the success of strategies managing resource use more efficiently and sustainably methodologies are required to comprehensively assess resource use and related impacts. This thesis provides four methodologies to improve the assessment of abiotic and biotic resource use in the context of sustainability on product and regional level. For the method to assess abiotic resources use on product level overall 21 aspects are considered as relevant and indicator for quantification are provided. In order to determine socio-economic supply chain restrictions a new approach is developed, considering geopolitical, political and regulatory aspects affecting resource extraction and use. Further, screening indicators are established to evaluate the societal acceptance of resources with regard to compliance with social and environmental standards. To assess the availability of terrestrial biotic resources in product systems a comprehensive methodology is established, which includes 25 indicators. Further, an approach is proposed to combine assessment methodologies in a consistent way. This approach is applied to the developed method of this thesis leading to a combined methodology. The use of resources also has to be considered on macro-economic. Thus, a methodology is developed providing 25 indicators for the two dimensions criticality, consisting of the sub-dimensions (physical and socio-economic) availability and vulnerability, as well as societal acceptance. Several case studies are carried out to demonstrate the applicability of the developed methods and to confirm the need for a comprehensive assess of resource use on micro and macro level, e.g. case studies for smart phones and cars, for biofuels produced from rapeseed and soybean. The applicability of the methodologies is further enhanced by providing indicator results for 36 metals and four fossil raw materials. The assessment of abiotic and biotic resource use on product and regional level is improved significantly by establishing four scientifically robust yet applicable methodologies, which consider multiple aspects of resource use in all three sustainability dimensions.

Die Metropolregion Santiago (MRS) verzeichnete in den letzten Jahren ein großes Bevölkerungswachstum und einen Anstieg des Lebensstandards. Als Folge davon hat sich das Aufkommen von Siedlungsabfällen fast innerhalb von 10 Jahren verdoppelt. Die Daten für den aktuellen Zustand des Abfallmanagements wurden durch Feldforschungen, Fragebögen, Feldbesuche und durch eine systematische Auswertung von bereits vorliegender Literatur erhoben. Das integrative Nachhaltigkeitskonzept der Helmholtz-Gemeinschaft diente als konzeptioneller Rahmen für die Studie. Zur Bewertung des aktuellen Zustands des Abfallmanagements wurden Nachhaltigkeitsindikatoren identifiziert, deren aktuelle Werte bestimmt und Zielwerte festgelegt. Die Nachhaltigkeitsanalyse zeigt, dass die größten Defizite darin liegen, dass nahezu die gesamte Abfallmenge ohne jegliche Vorbehandlung deponiert wird. Damit verbunden sind lang andauernde Emissionen von Treibhausgasen. Um herauszufinden, wie der informelle Sektor im Abfallmanagement zur Nachhaltigkeit beiträgt, wurden veröffentlichten Erfahrungen mit informellen Müllsammlern in Lateinamerika analysiert. Dabei wurden die entsprechenden Akteure sowie etablierte Allianzen zwischen diesen Akteuren identifiziert. Schlüsselfaktoren für ein nachhaltiges Abfallmanagement unter Einbeziehung des informellen Sektors sind die Legalisierung der Schattenwirtschaft und feste Verträge mit Partnerunternehmen. Relevante Akteure für die Gestaltung der Arbeitsbedingungen des informellen Sektors sind Vertreter privater und öffentlicher Unternehmen, einzelne gesellschaftliche Gruppen sowie Vertreter von Nichtregierungsorganisationen. Schließlich wurden drei explorative Szenarien für das Bezugsjahr 2030 entwickelt: Business as Usual (BAU), Collective Responsibility (CR) und Market Individualism (MI). Das BAU-Szenario enthält eine getrennte Sammlung von Bioabfall und von Wertstoffen; hervorgerufen durch einen verstärkten Organisationsgrad der informellen Müllsammler und den Ausbau von Bring-Systemen. Die Errichtung mechanischer Sortierungsanlagen trägt zur Verwertung der Materialien und zum Recycling bei. Das entstehende Deponiegas und Biogas wird als erneuerbare Energiequelle genutzt. Das CR-Szenario enthält eine getrennte Sammlung von Bioabfall und Wertstoffen. Dies wird erreicht durch eine verstärkte Zusammenarbeit mit den jetzt organisierten Müllsammlern und durch den Ausbau von Bring-Systemen. Mechanische Sortierungsanlagen tragen zur Verwertung von Materialien und zum Recycling bei. Durch Abtrennung einer heizwertreichen Fraktion in mechanisch biologischen Anlagen werden Sekundärbrennstoffe produziert. Darüber hinaus werden, das entstehende Deponiegas sowie das in Vergärungsanlagen erzeugte Biogas energetisch genutzt. Im MI-Szenario sind Wiederverwertungsstrategien von untergeordneter Bedeutung. Es gibt kein Interesse an einer Zusammenarbeit mit den informellen Müllsammlern und keine Anreize für einen verstärkten Organisationsgrad in diesem Bereich. Deshalb bleibt die Branche weitgehend informell. Technologische Entwicklungen in diesem Szenario enthalten die mechanische Sortierung von gemischtem Abfall und die energetische Verwertung von Deponiegas. Die Ergebnisse zeigten, dass das Pro-Kopf-Aufkommen an Siedlungsabfällen im Jahr 2030 in allen Szenarien deutlich höher als im Jahr 2007 ist und der festgelegte Zielwert von 1,6 kg/Kopf/Tag nicht erreicht wurde. Den höchsten Wert (2,0 kg/Kopf/Tag) weist das MI-Szenario auf, der niedrigste Wert (1,8 kg/Kopf/Tag) wurde im CR-Szenario gefunden. Eine Vorbehandlung der gesammelten gemischten Siedlungsabfälle findet nur im CR-Szenario statt, der entsprechende Wert beträgt 18 %, der Zielwert wird damit nicht erreicht. Die höchsten Treibhausgasemissionen treten im MI-Szenario (295 kg CO2-eq/Kopf/Jahr) auf, den niedrigsten Wert (155 kg CO2-eq/Kopf/Jahr) findet man im CR-Szenario. All diese Werte sind, verglichen mit dem festgelegten Zielwert von 71 kg/Kopf/Jahr, deutlich zu hoch. Der Zielwert für die Wiederverwertungsquote wurde im CR-Szenario erreicht (43 %), den niedrigsten Wert zeigt das MI-Szenario (20 %). Die Zielwerte für das Einkommen der Müllsammler wurden im CR-Szenario erreicht (128 %). Im MI-Szenario beträgt dieser Wert lediglich 51 %. Die Kosten für das Abfallmanagement im Verhältnis zum Bruttoinlandsprodukt sinken in den drei Szenarien. Aus den Ergebnissen lässt sich ableiten, dass ein Einbeziehen von mehreren Faktoren erforderlich ist, um die Nachhaltigkeit des Abfallmanagementsystems in den drei Szenarien zu steigern und dass es von wesentlicher Bedeutung ist, schon vorhandene und gut funktionierende Subsysteme, wie das der informellen Müllsammler, zu nutzen und zu stärken. Ebenso ist die Umsetzung robuster Behandlungstechnologien, die einen Beitrag zur Reduktion negativer Umweltauswirkungen leisten, zu forcieren. Diese Technologien sollten preiswert sein, um ihren Einsatz auch unter wirtschaftlich vertretbaren Gesichtspunkten zu ermöglichen. The Metropolitan Region of Santiago (MRS) has experienced a large growth in population in recent years and a rise in the standard of living. Therefore, its municipal solid waste (MSW) has almost doubled in 10 years. Data about the current situation of MSW management in MRS were collected during field research, interviews, field visits and by a systematic evaluation of existing documentary literature. The Integrative Sustainability Concept of the Helmholtz Association provided a conceptual framework for the study. The sustainability analysis showed that the largest deficits are in the current amount of MSW deposited at sanitary landfills without any pre-treatment, and the emission values of greenhouse gases associated with waste treatment and final disposal. To find out if and how the informal waste sector contributes to sustainability, experiences of organization of informal primary collectors in Latin America were analyzed. The key factors which have an influence on their working conditions were identified. These factors include the existence of a legal framework for the informal waste sector; the existence of alliances with production companies guaranteeing a reliable industrial market for secondary raw materials and expansion of activities beyond collection of recyclables. Key stakeholders included people from the public and the private sector, from the civil society and from NGOs. Three explorative scenarios were developed for the year 2030: Business as Usual (BAU), Collective Responsibility (CR), and Market Individualism (MI). Waste generation, waste composition and different practices of waste collection, recovery and treatment were taken into account for the scenarios formulation. The BAU scenario incorporated separate collection of biowaste, recyclable materials with some participation of organized primary collectors and an expansion of drop-off systems. The mechanical sorting of mixed waste was introduced. The utilization of landfill gas as an energy source was promoted and the production of biogas in anaerobic digestion plants was implemented. The CR scenario incorporated separate collection of biowaste, commitment to work together with the primary waste collectors and an expansion of drop-off systems. The mechanical and mechanical biological treatment of mixed waste was introduced. The utilization of landfill gas as an energy source is promoted and the production of biogas in anaerobic digestion plants was implemented. In the MI separate collection of biowaste and recyclable materials was irrelevant. An organization of the informal primary collectors did not take place. Mechanical sorting of mixed waste was introduced. Utilization of landfill gas as an energy source was promoted. The results showed that the generation flux of MSW is at least 50% larger in all scenarios in 2030 compared to the year 2007, exceeding the limit value proposed. The highest value (2.0 kg/(person•day) is obtained in the MI scenario, and the lowest (1.8 kg/(person•day)) in the CR scenario. Pre-treatment of mixed MSW collected is only achieved in the CR scenario with a value of 18%, however, the target value is not achieved. The highest greenhouse gas emission value is obtained in the MI scenario with 295 kg CO2eq/(person•year), the lowest value of 155 kg CO2-eq/(person•year) is obtained in the CR scenario; a value that is still very high in comparison with the suggested target. The largest recycling rate is obtained in the CR scenario (43%), which is better than the target value proposed, the lowest recycling rate is obtained in the MI scenario (20%). The income of primary collectors in comparison with the income of one individual household is improved significantly in the CR scenario (128%), in the MI scenario, earnings of primary collectors decreased to 51%. The share of GDP spent on MSW management is lower in 2030, compared to the year 2007, in all scenarios the largest value of 0.17% is obtained in the CR scenario, and the lowest value of 0.14% is obtained in the MI scenario. The results of the evaluation of the scenarios showed that the largest sustainability deficits are the amount of mixed MSW which undergoes pre-treatment, the greenhouse gas emissions associated to MSW treatment and disposal, as well as the share of GDP spent on MSW management. The results obtained suggested that an integration of several factors is required to increase sustainability. It is essential to strengthen and take advantage of the subsystems which are working within the waste management system, as in the case of the informal sector. In addition to the implementation of flexible treatment technologies which help to decrease negative environmental impacts. Moreover, the costs of these technologies should be affordable, allowing a better financial management.