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This thesis comprises three papers examining the impact of competitive pricing or competition on participants in energy markets. The scope of each paper is narrow but focused, dealing with one particular aspect of competition in each market under study. It is hoped that results from these three studies could provide valuable policy lessons to public policy makers in their task to create or maintain competition in different energy markets, so as to improve efficiencies in these markets. The first and second papers examine the load shifting behavior of industrial customers in Ontario under real time pricing (RTP). Using Hourly Ontario Energy Price (HOEP) data from 2005 to 2008 and industry-level consumption data from all industrial customers directly connected to the transmission grid, the first paper adopts a Generalized Leontief specification to obtain elasticities of substitution estimates for various industry groups, while the second paper adopts a specification derived from standard consumer theory to obtain price elasticity estimates. The findings of both papers confirm that in some industries, industrial customers who are direct participants of the wholesale market tend to shift consumption from peak to off-peak periods in order to take advantage of lower off-peak prices. Furthermore, in the first paper, a demand model is estimated and there is evidence that the marginal effect of hourly load on hourly price during peak periods is larger than the marginal effect during off-peak periods. An important policy implication from the results of these papers is that while RTP is currently limited to industrial customers, it does have positive spillover effects on all consumers. The third paper uses a unique panel dataset of all retail gasoline stations across five Canadian cities from late-2006 to mid-2007 to examine the effect of local competition on market shares and sales of individual stations. The base empirical specification includes explanatory variables representing the number of same brand stations and the number of different brand stations within a 3km radius to identify brand affiliation effect. It is found that the number of local competitors is negatively correlated with market share and sales. More interestingly, a same brand competitor has a larger marginal impact on market share and sales than a competitor of a different brand. These findings suggest that additional local competition leads to cannibalization of market share among existing stations, rather than create new demand. Another implication is that relying only on the number of different brands operating within a geographic market could understate the competition intensity in the local market.

The awareness of the effect emissions have on the environment and climate has risen in the last decades. This has caused strict regulations of greenhouse gas emissions. Greenhouse gases cause global warming which may have devastating environmental effects. Most of the fuels commercially available today are fossil fuels. There are two major effects of using fuels with fossil origin; the source will eventually drain and the usage results in an increase of greenhouse gases in the atmosphere. Fuels that are created from a renewable feedstock are often referred to as alternative fuels and under ideal conditions they are greenhouse gas neutral, meaning that the same amount of greenhouse gases is released during combustion as the source of the fuel have absorbed during its growth period. This evaluation method is known as a well-to-wheel analysis which besides emissions also evaluates energy efficiencies during both the production and the combustion phases. By evaluating results of well-to-wheel analyses along with fuel properties and engine concept characteristics, this report presents which driving scenario that is suitable for different powertrain configurations. For example, vehicles operating in high populated areas, as cities, have a driving scenario that includes low velocities and multiple stops while vehicles in low populated areas often travel long distances in higher speeds. This implies that different powertrains are suitable in different regions. By matching favorable properties of a certain powertrain to the properties important to the actual driving scenario this report evolves a fuel infrastructure that is suitable in Sweden.

In this study, canola oil has been selected for the test on a diesel engine and its suitability as an alternative fuel has been examined. To decrease the high viscosity of canola oil, the effect of temperature on viscosity has been researched. Then the fuel delivery system has been modified to heat canola oil before injecting the oil into the combustion chamber. Also, ethanol has been tested as an additive by blending with canola oil. An experimental setup has been installed according to standards to carry out tests. The set up has been controlled with a computer to take measurements more precisely and to perform experiment automatically. Experimental investigations have been conducted on a four cylinder, direct injection diesel engine. Full load-variable speed tests have been conducted to evaluate engine performance parameters. In addition 13 mode ESC test cycle has been performed to determine the exhaust emissions. Engine performance and emissions characteristics of canola oil and canola-ethanol blend containing 30% ethanol have been compared with those of baseline diesel fuel. Experimental results show that engine performance decreased for canola oil. Addition of ethanol into canola oil has been noticed to improve performance a little with respect to pure canola oil. Although, maximum performance has been obtained with diesel fuel, minimum specifics energy cost is obtained with canola oil. It has been observed that hydrocarbon (HC) emissions decrease with canola oil, blending ethanol with canola oil increase HC emissions and maximum values are read for diesel fuel. Carbon monoxide (CO) emissions have been observed to be the highest for canola oil but blending ethanol has a decreasing effect on CO emissions. As for particulate matter (PM), use of canola oil has been seen to be more pollutant than diesel but adding ethanol in canola reduces PM emissions significantly.

Das Konzept „Downsizing“ für Otto- und Dieselmotoren zur Verbesserung von Kraftstoffverbrauch und Schadstoffemission ist inzwischen durch viele praktische Beispiele und theoretische Untersuchungen zweifelsfrei bestätigt worden. Da „Downsizing“ aber untrennbar mit der Aufladung verbunden ist, wächst der Bedarf nach Aufladetechnologien, die das Hauptmanko des „Downsizing“ – das mangelhafte Drehmoment bei niedriger Motordrehzahl – überwinden. Mit zunehmender spezifischer Leistung und damit höheren Aufladegraden tritt diese Problematik immer stärker in den Vordergrund. Vor diesem Hintergrund hat sich für den Pkw-Dieselmotor die Aufladung mit VTG durchgesetzt. Beim Ottomotor wurde bislang der Schritt vom einfacheren Wastegate-Lader zur VTG noch nicht unternommen. Die Gründe dafür sind insbesondere in der höheren thermischen Belastung, aufgrund der höheren Abgastemperatur, und der größeren Luftdurchsatzspanne zu finden. Andererseits besteht inzwischen speziell beim Ottomotor ein großer Bedarf bezüglich der Verbesserung des Kraftstoffverbrauches und der Fahrdynamik in Kombination mit der Turboaufladung. Vor dem Hintergrund der in den letzten Jahren durchgeführten Weiterentwicklungen auf dem Gebiet der Benzindirekteinspritzung und der Aufladetechnik, stellt sich inzwischen verstärkt die Frage, ob durch den Einsatz einer VTG am Ottomotor ähnlich große Verbrauchseinsparungen und Verbesserungen in der Fahrdynamik erzielt werden können, wie dies vor einigen Jahren beim Pkw-Dieselmotor der Fall war. Im Rahmen der durchgeführten Arbeit wurden die Potentiale einer VTG an einem direkteinspritzenden Ottomotor eingehend durch Experimente und Motorprozesssimulation untersucht. Bei der direkten Übertragung der heute üblichen Diesel-VTG-Technik auf die Anwendung am Ottomotor können allerdings nur unwesentliche Verbesserungen beim spezifischen Kraftstoffverbrauch erzielt werden. Um die volle Drehzahlspanne des Ottomotors in seiner Basisabstimmung bedienen zu können, muss der Verstellbereich der VTG extrem ausgereizt werden, was Wirkungsgradnachteile mit sich bringt. Mit dem Übergang auf ein 2-flutiges Zwillingsstromturbinengehäuse in Kombination mit VTG wird es möglich, den Gaswechsel des Motors zu verbessern, da der Auslassvorgang der einzelnen Zylinder weniger durch die anderen Zylinder behindert wird. Der Effekt ist allerdings wesentlich schwächer ausgeprägt als bei einem 2-flutigen Wastegate Lader, da hier die Flutentrennung bis kurz vor das Turbinenrad erfolgen kann. Bei der VTG-Zwillingsstromturbine endet die Trennung konstruktionsbedingt bereits vor dem Leitgitter. Im Bereich des beschaufelten Ringkanales treffen die beiden bis dorthin getrennten Abgasstränge aufeinander und beeinflussen sich hier wieder gegenseitig, wobei die negativen Auswirkungen geringer sind als bei einer 1-flutigen Turbine, ganz ohne Trennung im Turbinengehäuse. Die bessere Nutzung der kinetischen Energie aus dem Vorauslassstoß, die bei Stoßaufladung mit getrennt geführten Abgaskanälen üblicherweise möglich ist, kann allerdings bei einer VTG-Turbine nicht erreicht werden. Speziell im unteren Motordrehzahlbereich, wo die Leitschaufeln weit geschlossen sind, werden die Druckpulsationen stark gedämpft und haben somit nur noch einen geringen Anteil an der Totalenthalpie des Abgases. Wie sich aus den Untersuchungen zeigte, kann dieser Nachteil der VTG aber durch den kleineren Turbinendurchsatz bei kleiner Schaufelstellung überkompensiert werden, wodurch das Drehmoment bei niedrigen Motordrehzahlen angehoben werden kann. Eine wesentlich bessere Flutentrennung kann durch die Verwendung einer VTG-Doppelstromturbine erreicht werden. Durch zwei über den Turbinenumfang getrennt geführte Spiralkanäle können die Überströmquerschnitte verkleinert, und damit die gegenseitige Beeinflussung der Abgasströme wesentlich verringert werden. Die Verhältnisse sind in dieser Ausführung vergleichbar mit Wastegate- Zwillingsstromturbinen, was die Effektivität der Flutentrennung anbelangt. Das volle Potential dieser optimierten Flutentrennung kann durch eine geänderte Applikation der Nockenwellenverstellungen im Motorkennfeld ausgeschöpft werden. Es ist damit möglich, längere Ventilüberschneidungen im unteren Motordrehzahlbereich zu realisieren und damit den Spülluftanteil in diesem Kennfeldbereich wesentlich zu steigern. Diese Maßnahme hat einen sehr positiven Einfluss auf die Motorbetriebswerte aufgrund: • Verringerter Klopfempfindlichkeit durch Reduktion des Restgasanteiles. • Absenkung der mittleren Abgastemperatur vor Turbine und damit der Möglichkeit, das Verbrennungsluftverhältnis anzuheben. • Verringerung der notwendigen Durchsatzspanne für Verdichter und Turbine und damit der Möglichkeit den Lader bei besseren Wirkungsgraden zu betreiben. Aufgrund des mit der Doppelstromanordnung begrenzten Zuströmquerschnittes über den Umfang der Turbine (180° pro Turbinenstrang) stellt sich allerdings ein geringerer Maximaldurchsatz für die Turbine ein. Die Simulationsergebnisse haben gezeigt, dass dadurch der mittlere Abgasdruck vor Turbine im oberen Volllastdrehzahlbereich ansteigt. Um dies zu verhindern, kann die Doppelstromturbine mit einer so genannten Stau–Stoß–Umschaltung versehen werden, mit der die beiden Turbinenstränge bei hohen Motordrehzahlen verbunden werden. Bei geöffnetem Umschaltventil kann sich das Abgas auf beide Turbinenstränge verteilen, und die Pulsation wird zusätzlich reduziert. Beide Effekte bewirken ein Absinken der Turbinenleistung und damit die gewünschte Begrenzung des Ladedruckes. Gleichzeitig ist es auch möglich, das Stoß–Stau–Umschaltventil als zusätzliches Wastegate zu betreiben, wodurch der Durchsatzbereich der Turbine noch weiter gesteigert werden kann. Die Kombination der geschilderten Maßnahmen: • VTG mit Doppelstromturbine • Stoß-Stau-Umschaltung • Vergrößerte Ventilüberschneidung hat bei den durchgeführten Untersuchungen zu einer Steigerung des stationären Volllastdrehmomentes von 40 % bei nM = 1500 1/min geführt, bei gleichzeitiger Verbesserung des Spüldruckgefälles um ca. 400 mbar im Nennleistungspunkt gegenüber dem 1-flutigen Wastegate-Basislader. Im Instationärbetrieb konnte am Beispiel eines Lastsprunges bei nM = 1800 1/min eine Verkürzung der Zeit bis zum Erreichen von 90 % des Nennmomentes um ca. 50 % festgestellt werden. Obgleich auf Basis der untersuchten Varianten bezüglich der aerodynamischen Auslegung der Einzelkomponenten, der Regelbarkeit der VTG und der mechanischen Haltbarkeit noch weitere Entwicklungsaktivitäten notwendig sein werden, kann aufgrund der sehr positiven Untersuchungsergebnisse von einem großen Potential für die Aufladung von DI-Ottomotoren mit variabler Turbinengeometrie ausgegangen werden.

The United States Environmental Protection Agency has estimated that over 111 million people reside in areas that exceed the National Ambient Air Quality Standards for ozone. One major source of the chemical precursors (nitrogen dioxides and volatile organic compounds (VOCs)) for ozone are motor vehicles. The overall goal of this research is to improve the knowledge base related to VOC refueling and evaporative emissions from motor vehicles. Refueling, running loss, hot soak, and diurnal loss total and speciated VOC emissions were investigated. A total of 12 uncontrolled refueling events were completed and involved the determination of volumetric flow rates of gasoline vapor during refueling, as well as total and speciated VOC concentrations. Total VOC emissions were compared with two commonly used algorithms. Speciated VOC vapor profiles were compared with two published gasoline vapor profiles and theoretical predictions based on knowledge of liquid composition and environmental conditions. An evaluation of refueling emissions impacts on ozone formation potentials using MIR was completed and results were compared against speciated emissions and MOBILE-based total VOC emissions estimates coupled with a default speciation profile. Refueling VOC emissions and resultant ozone formation potential may be underestimated in existing emission inventories, particularly during the summer ozone season, A model was developed to predict the speciation of VOCs associated with evaporative emissions from motor vehicles. Model-predicted speciation profiles were evaluated using SHED studies. Running loss, hot soak and diurnal emissions were included in each test. Total VOC emissions measured during each test were compared against MOBILE6 predicted emissions. An evaluation of evaporative emissions impacts on ozone formation potentials using MIR was completed, comparing measured and predicted emissions. The measured:predicted speciation results ranged between 0.93 and 1.11 and had an average value of 1.02. For the conditions tested, MOBILE6 underestimated evaporative emissions in 20 of 24 comparisons. MOBILE6-based ozone formation potentials may be underestimated.

D. Tech. Mechanical Engineering. / Discusses how to reduce the negative impacts of petroleum oil based fuels in reciprocating engines on the environment through the use of oxygenated (alcohol) blends, while not deteriorating engine performance. The specific objectives are as follows: To evaluate the performance characteristics of n-butanol-diesel blends: B5, B10 and B20, in a direct-injection turbo-charged diesel engine and to compare findings with a study that was carried out by others (Sayin, 2010). To compare the performance, combustion and emission characteristics of dual alcohol-gasoline with single alcohol-gasoline blends fired in a naturally-aspirated (NA) spark ignition (SI) engine. To compare the combustion and emission characteristics of dual alcohol (methanol-n-butanol-gasoline) blends with single alcohol (methanol-gasoline) blends in a single-cylinder SI engine. To evaluate the combustion and regulated emission characteristics of DF and n-butanol/diesel blends (B5, B10, and B20 where B5 represents 5 % shared volume of n-butanol to 95 % diesel fuel) fired in a high load turbo-charged diesel engine and to compare the findings with a study that was conducted by Raslavicius & Bazaras, (2010).

Σε παγκόσμια κλίμακα αλλά και εντός των ελληνικών συνόρων κερδίζει συνεχώς έδαφος η άποψη, τόσο από το καταναλωτικό κοινό όσο και από την πλευρά των πολιτικών παραγόντων, ότι οι τιμές της λιανικής βενζίνης δεν αντανακλούν το κόστος του αργού πετρελαίου. Συγκεκριμένα υπάρχει διάχυτη η πεποίθηση ότι οι τιμές της βενζίνης αποκρίνονται ασύμμετρα στις μεταβολές της τιμής του αργού πετρελαίου-ενώ δηλαδή οι αυξήσεις περνούν άμεσα στις τιμές, δεν ισχύει το ίδιο και στην περίπτωση μείωσης των τιμών του αργού πετρελαίου. Με αφορμή αυτήν την άποψη, ελέγξαμε για ύπαρξη ασύμμετρων αποκρίσεων της τιμής της βενζίνης με δεδομένα για την Ελλάδα από την περίοδο 30 Σεπτεμβρίου του 2002 έως τις 15 Απριλίου του 2009. Βρήκαμε ότι, θετικές ασυμμετρίες στην τιμή ισορροπίας (όταν η τιμή της αμόλυβδης είναι πάνω από την τιμή ισορροπίας όπως αυτή ορίζεται από την τιμή του πετρελαίου) εμμένουν και δεν τείνουν να εξαλειφθούν, ενώ αντιθέτως, αρνητικές αποκλίσεις της τιμής της αμόλυβδης από την «δίκαιη» τιμή της τείνουν να εξαλειφθούν σε σύντομο χρονικό διάστημα. Η διαπίστωση αυτή μπορεί να ερμηνευτεί από τα χαρακτηριστικά που διέπουν την ελληνικά αγορά πετρελαιοειδών και περιορίζουν την ανάπτυξη του ανταγωνισμού-ο εφοδιασμός των επιχειρήσεων λιανικής εμπορίας γίνεται για παράδειγμα με την χρήση συμβάσεων εμπορικής συνεργασίας μεταξύ πρατηριούχων και εταιριών εμπορίας πετρελαιοειδών-που περιλαμβάνουν περιοριστικούς του ανταγωνισμού όρους στη διακίνηση των εμπορευμάτων. Αναφορικά με τους λόγους της ασύμμετρης απόκρισης των τιμών λιανικής βενζίνης, εκτός από τις αιτίες που αναφέρονται στην κλασσική Βιβλιογραφία (Δύναμη της αγοράς, δαπανηρή προσαρμογή της παραγωγής και των αποθεμάτων, κόστη έρευνας κτλ) αναφερθήκαμε και σε δευτερεύουσες αιτιάσεις οι οποίες μπορεί να αποδειχθούν εξίσου σημαντικές (η ύπαρξη μελλοντικών συμβολαίων, η σχετική ζήτηση, η επιλογή λογιστικών πρακτικών, η επίδραση των οικονομικών κύκλων και των δομικών αλλαγών). Επιπλέον, αναφερθήκαμε στις κυριότερες από την πληθώρα των σχετικών μελετών που έχουν πραγματοποιηθεί παγκοσμίως και ειδικότερα στα υποδείγματα που έχουν προταθεί ως καταλληλότερα για την ανάλυση του ζητήματος της ασύμμετρης απόκρισης των λιανικών τιμών της βενζίνης αλλά και στους λόγους για τους οποίους αυτά δίνουν διαφορετικά αποτελέσματα. / World-wide and within the borders of Greece, is gaining continually ground, both to the consumers and politicians, the opinion that, retail gasoline prices don’t reflect the crude oil cost. Specifically, there is a strong belief that gasoline prices, respond asymmetrically to crude oil price changes - while for example, the increases pass through immediately to prices, the same doesn’t hold in the case of crude oil prices reduction. With incentive this point of view, we tested for the existence of asymmetric responses of gasoline price with data for Greece, for the period 30 September 2002 to 15 April 2009. We found that, positive asymmetries in equilibrium price (when unleaded gasoline price is above the equilibrium price as it is determined from the oil price) persist and don’t tend to eliminate, whereas, negative deviations of unleaded gasoline price from it’s “fair” price, tend to eradicate in short time. This finding, can be interpreted by the characteristics that rule the Greek oil market and restrict the development of competition – the supply of retail trade companies, is held for instance, with the use of commercial co-operation contracts, between the owners of the gas stations and the oil products trading firms, that incorporate competition restrictive conditions in the distribution of the commodities. As regard the reasons of asymmetric response of retail gasoline prices, apart from the causes that have been referred in the classic bibliography, (market power, costly output and inventories adjustment, search costs, etc), we mentioned and secondary reasons that may proved to be the same important (the existence of future contracts, the relative demand, the choice of the accounting practices, the effect of economic cycles and structural changes). Furthermore, we referred to the main, from the plentitude of the relative studies that have taken place worldwide and particularly to the models that have been suggested as proper for the analysis of the issue of asymmetric response of retail gasoline prices, as well as and to the causes for which they yield different results.

The purpose of this study is to develop catalysts for conversion of synthesis gas (H₂ and CO) to higher alcohols, primarily ethanol and propanol. Crude oil is consumed at a rate of more than 20 million barrels a day in the United States, mainly for producing fuels and chemical feedstocks. However, the total amount of crude oil is limited, and alternative ways of producing alcohols as precursors for chemical feedstocks are desirable. In this study, using a known K/MoS₂/metal oxide catalyst as the starting point, two different approaches were explored to improve catalytic properties: 1) Co promotion on K/MoS₂/mixed metal oxide (MMO) catalysts, and 2) Preparation of K/MoS₂/metal oxide catalysts with molybdenum carbide as a precursor, instead of molybdenum oxide. With respect to Co promotion on K/MoS₂/MMO catalysts, the effect of varying the Co content in the K/Mo-Co/MMO catalysts prepared by a co-impregnation method did not produce significant changes in catalytic acitivities or selectivities. It was due to the premature precipitation of cobalt molybdate during synthesis. Cobalt molybdate precipitation can generally be prevented by using water as a solvent, but this approach is not appropriate for this study because of the use of hydrotalcite-derived mixed metal oxide as the support. Co loadings on K/Mo/MMO-Co catalysts did not change selectivities significantly, either. However, they changed catalytic activities, represented by gas hourly space velocity (GHSV) required to obtain 8% conversion while maintaining high selectivities for higher alcohols. As a result, C ₂₊ alcohol productivities reached 0.01g(alcohol)/g(catalyst)/hr with Co loadings higher than 8%. With respect to using Mo2C as the precursor of Mo species instead of MoO3, comparisons between catalysts with different precursors for Mo species and different pretreatments were investigated. In this study, both K/Mo catalysts supported on MgO and α-Al₂O₃ showed similar tendencies of catalytic activities and selectivities. The highest C₂₊ alcohol selectivities and productivities were obtained on presulfided MoO₃ catalysts on both supports. In comparison of K/Mo ₂C catalysts with different pretreatments, higher C₂₊ alcohol selectivities and lower MeOH selectivities were obtained on presulfided catalysts compared to non-pretreated catalysts.

This thesis comprises three papers examining the impact of competitive pricing or competition on participants in energy markets. The scope of each paper is narrow but focused, dealing with one particular aspect of competition in each market under study. It is hoped that results from these three studies could provide valuable policy lessons to public policy makers in their task to create or maintain competition in different energy markets, so as to improve efficiencies in these markets. The first and second papers examine the load shifting behavior of industrial customers in Ontario under real time pricing (RTP). Using Hourly Ontario Energy Price (HOEP) data from 2005 to 2008 and industry-level consumption data from all industrial customers directly connected to the transmission grid, the first paper adopts a Generalized Leontief specification to obtain elasticities of substitution estimates for various industry groups, while the second paper adopts a specification derived from standard consumer theory to obtain price elasticity estimates. The findings of both papers confirm that in some industries, industrial customers who are direct participants of the wholesale market tend to shift consumption from peak to off-peak periods in order to take advantage of lower off-peak prices. Furthermore, in the first paper, a demand model is estimated and there is evidence that the marginal effect of hourly load on hourly price during peak periods is larger than the marginal effect during off-peak periods. An important policy implication from the results of these papers is that while RTP is currently limited to industrial customers, it does have positive spillover effects on all consumers. The third paper uses a unique panel dataset of all retail gasoline stations across five Canadian cities from late-2006 to mid-2007 to examine the effect of local competition on market shares and sales of individual stations. The base empirical specification includes explanatory variables representing the number of same brand stations and the number of different brand stations within a 3km radius to identify brand affiliation effect. It is found that the number of local competitors is negatively correlated with market share and sales. More interestingly, a same brand competitor has a larger marginal impact on market share and sales than a competitor of a different brand. These findings suggest that additional local competition leads to cannibalization of market share among existing stations, rather than create new demand. Another implication is that relying only on the number of different brands operating within a geographic market could understate the competition intensity in the local market.