Die anspruchsvollen Zielsetzungen zum CO2-Ausstoß von Kraftfahrzeugen verlangen immer stärker nach hocheffizienten Fahrzeugkonzepten und werden zukünftig zu deutlich höheren Elektrifizierungsanteilen der Antriebe führen. Die große Herausforderung liegt dabei in der Lösung des Zielkonfliktes zwischen voll elektrischem Fahren und erstfahrzeugtauglicher Reichweite. Im Rahmen eines Forschungsprojektes zur Konzeption von Hybridfahrzeugen hat die BMW Forschung ein Konzeptfahrzeug entwickelt, das im urbanen Bereich emissionsfrei betrieben werden kann und dennoch alltagstauglich für spontane längere Fahrten nutzbar ist (Abbildung 1). Die für dieses Projekt abgeleiteten Ziele waren ein Verbrauch von < 2,5 l im Ladungserhaltungsbetrieb, eine E-Reichweite von 100 km, eine BMW-adäquate Beschleunigung von < 8 sec von 0 auf 100 km/h, eine erstfahrzeugtaugliche Höchstgeschwindigkeit von 180 km/h, ein Raumangebot auf Niveau heutiger viersitziger Coupés im Kompaktsegment und eine Gesamtreichweite von 1.000 km (Eiletz 2015a). Im Rahmen des Beitrags werden sowohl Prozess und Vorgehensweise bei der Gestaltung des Hocheffizienz-Konzeptfahrzeugs als auch die Ergebnisse des Forschungsprojektes dargelegt.

Rural areas continue to be home to the majority of the population in Africa. The importance of providing modern energy to rural areas cannot, therefore, be overemphasized.  No wonder that at presently the major energy resource in Mozambique is fuel wood biomass. Total population is estimated to be 25 million and more than 80% of the energy consumed in the country comes from fuel wood biomass. The energy from the main grid covers about 45.3% of Mozambican population which 26.8% comes from the National Grid and the remaining 18.5% from renewables and other sources. People outside the grid are mainly those living in rural and suburban areas. For most rural households in the region, biomass fuels continue to be the dominant fuel of choice. The present document suggests possible options that could have greater impact on rural clean energy development. Such options could be Solar Photovoltaic and Solar Thermal energy, Wind and Micro- hydropower for pumping water or electricity generator and Biofuels. These energy options are receiving adequate attention from policy makers and are improving rural life. These are useful Renewable Energy sources available in the rural areas since they can supply reliable, relatively cost-effective electricity for basic needs in developing countries. They can be used to improve the lives of people in many ways, including supplying clean electricity to light homes, hospitals, schools, small shops, and other infrastructures, pumping water, etc. For example, using the natural resource of wind, sunlight, rivers and Jatropha plants can improve the lives of many people in general and those in rural areas in particular. This paper aims to describe and discuss the present status of renewable energy technologies in developing countries (case of Mozambique), to define the plausible ways for expanding rural electrification and improving the life conditions for the rural population.

This project work focuses on the feasibility study of a hybrid PV-Wind System for rural electrification at the Estatuene Locality in southern Mozambique. This is in line with electricity network expansion, which, in Mozambique shows high implementation cost and low operation cost. Through field research, an analysis was made of the actual electrical demand in the Estatuene rural community. The wind data was collected from the installed weather stations in the region while the solar data were extracted internally from the HOMER software by introducing the site coordinates. All the configurations, simulations and selection of hybrid systems were also made using HOMER. For the Estatuene rural community it was estimated a scaled annual average demand of 9.4 kWh/day with a peak load of 1.4 kW for DC charge; and a total scaled annual average of 133 kWh/day with a peak load of 15.3 kW for AC Charge. The annual mean solar potential is 5.205 kWh/m2/d, and the mean wind speed is 4.84 m/s for 12 meters above the ground. Thus the calculations and the selection of the best configuration of the hybrid system were crossed out with the technical specifications and costs of photovoltaic panels, wind turbines, power converter, batteries, and the electricity network, specifically for the comparison between an optimum hybrid system solution and two separate ones. The calculations presented an analysis of the technical and the financial viability of the selected hybrid system for local electric power production.

This study examines the concept of the evolution of electricity sector in Tanzania.Electrification of Africa has raised large discussion and thus, nine scenarios based ondifferent production pathways and demand projections are formulated. The studyconsiders both grid based centralized electricity and decentralized power production.The main differentiation is between a centralized electricity system and decentralizedpower that are closer to demand. A model is created using three modeling tools(Answer-OSeMOSYS, LEAP and MESSAGE) and the results are presented andcompared. Finally, different funding options for electricity expansion projects inTanzania are explored in order to investigate the feasibility of the scenarios as well asa geopolitical analysis is carried out.

The high cost of grid extension to rural areas, often characterized by scattered communities with low load densities, requires the use of low cost electrification technologies to ensure economic viability. In Single Wire Earth Return (SWER) power distribution networks, the earth itself forms the current return path of the single phase system leading to significant cost savings on conductors, poles and poletop hardware compared to conventional systems. However, challenges exist in SWER with regard to earthing and safety as well as the dependence on earth conductivity to supply consumer loads. This work presents models for the optimal planning of SWER distribution networks. The earth return path is modeled as a conductor based on the Carson line model taking into consideration specific ground properties of the considered location. A load flow algorithm for radial SWER networks is subsequently formulated whereby both overhead line and ground voltages and currents are determined. First, heuristic planning models are developed based on the SWER load flow model. The objective of the heuristic models is to determine the optimum feeder configuration and overhead conductor subject to SWER load flow constraints and load growth over several time periods. Whereas the resulting solutions are good, they may not necessarily be globally optimum. Optimization models are then developed using mixed integer non-linear programming (MINLP) with the aim of obtaining global solutions to the SWER network planning problem. Since the MINLP formulations are limited to the accurate analysis of limited size networks, considerations and approximations for the analysis of larger networks are presented. The developed models are applied to a case study in Uganda to test their practical application. In addition, comparative studies are done to determine how the proposed optimization models compare with previous distribution planning models. The numerical analysis includes the impact of deterministic distributed generation on the SWER planning problem. Results showed consistent performance of the proposed heuristic and optimization models, which also compared well with conventional models. The optimization models gave more cost-effective solutions to the SWER planning problem than the heuristic models. However, the former models had higher computational cost than the latter. The inclusion of distributed generation allowed for cheaper network solutions to be obtained. The models are applicable to the planning of Single Wire Earth Return networks for isolated mini-grids, grid-extension to previously un-electrified rural areas as well as the upgrade of SWER feeders in existing installations. / <p>QC 20121207</p> / Sustainable Technological Development in the Lake Victoria Region

Die DB-Strecke 4950 (Heilbronn – Öhringen – Schwäbisch Hall – Crailsheim) ist gegenwärtig zu etwa zwei Drittel elektrifiziert. Auf dem mittleren Teilstück zwischen den Betriebsstellen Öhringen-Cappel (km 90,080) und Schwäbisch Hall-Hessental (km 57,667) existiert nach wie vor auf einer Strecke von rund 32 km keine Fahrleitung. Die vorliegende Studienarbeit hat das Ziel, den gegenwärtigen Zustand des nicht elektrifizierten Streckenabschnitts zu dokumentieren und zu bewerten, an welchen Stellen der Bestandsinfrastruktur für eine Elektrifizierung Anpassungsbedarf besteht. Erforderliche Baumaßnahmen zur Ertüchtigung der Strecke, im Einzelnen zur Herstellung der erforderlichen Lichträume bei Kunstbauten und zur Ertüchtigung des Unterbaus für die Herstellung der Mastfundamente, werden untersucht, bewertet und zweckmäßige Verfahrensweisen vorgeschlagen. Ferner wird der gegenwärtige sowie der für die kommenden Jahrzehnte prognostizierte Verkehrsbedarf (Personen- und Güterverkehr) der Strecke betrachtet, um daraus Vorschläge zum Betriebskonzept und zur Anpassung der Bahnanlagen auf der Strecke Heilbronn – Crailsheim zu machen und um Möglichkeiten zur Kapazitätserweiterung der Strecke in Zukunft offen zu halten.:1. Ausgangssituation und Einführung 2. Betriebskonzepte und Verkehrspolitik auf der Strecke 3. Bewertung des gegenwärtigen Zustands des zu elektrifizierenden Abschnitts 4. Erforderliche Baumaßnahmen 5. Fazit

Global goals to reduce the greenhouse gases and CO2 emission has challenged many industries to innovate new technologies or shift to different products. Electrification of transportation has been considered a major improvement in this respect, which affects the entire transportation value chain including the manufacturing of heavy-duty vehicles. The importance and degree of changes that shifting toward electrification imposes on the truck manufactures value chain is subject to the study with a focus on the production stage of the value chain. The research also creates some insights to understand the sources of competitive advantage in the production of BEV.    Based on the authors’ knowledge and investigations, the contribution of this study in the research field is that the concept of the value chain together with Delphi method is implemented for the first time in the BEV industry to identify the impact of technology transformation on the production activities and competitive advantage. Furthermore, it contributes to highlight the unclarities in the BEV value chain activities that need more researches in order to create a more clear technology transformation path for the heavy-duty vehicle industry. The research findings imply that electrification has a big impact on the production value chain activities. The number of employees will be reduced that in turn creates a source of cost advantage for the company by reducing the cost per vehicle production. The assembly time is also shorter that makes it easier to respond to the market dynamic faster and reduces the cost of products storage. However, the risk for production stops is considered higher in BEV compare to ICE vehicles. Another finding is that the outsourcing of the components has a negative effect on the competitive advantage of the company and production efficiency. There is no difference between the impact of production activities on the company value chain in both BEV and ICE manufacturing. There is also a consensus on the more opportunities in BEV manufacturing to increase the production efficiency and lowering the cost.

Rural electrification serves as a tool to reach several of the United Nations Sustainable Development Goals (SDGs). However, challenges occur related to increased electricity access, involving financial, informational, technical and regulatory factors. Another issue concerning electrification is the potential climate effects that increased electricity production causes. To minimise emissions and energy losses, usage of renewable energy sources is a possible solution as well as increased decentralised electricity production. Microgrids enable both of these parts and therefore serve as a great solution to sustainably meet the increased demand of electricity. Therefore, the main purpose of this study is to investigate the potential of microgrids to sustainably contribute to an increased access to electricity. The study focuses on the electrical power situation in Thailand. The literature study covers the political strategies regarding rural electrification and implementation of renewable energy sources in Thailand’s electrical power system, and how the country is currently developing according to these strategies. The case study consists of a cost and emission analysis related to a pilot microgrid project in northern Thailand. The Provincial Electricity Authority (PEA) in Thailand initiated and built the microgrid project called Maesariang Microgrid, in MaeSariang District in the northern province Mae Hong Son. The purpose of the project was to improve reliability and quality of the power delivered to Mae Sariang District. The microgrid consists of a solar power plant, a hydro power station, diesel generators and a battery energy storage system (BESS). The results from the case study shows that implementation of the Maesariang Microgrid, in addition to power reliability and quality, resulted in both reduced cost of electricity generation (COEG) with 3 percent and carbon dioxide (CO2) emissions with 11 percent. Furthermore, emissions per generated electricity unit has reduced from 380 kg CO2 per MWhto 340 kg CO2 per MWh. By using a system model covering the current microgrid in Mae Sariang, three alternative microgrid compositions with different shares of installed renewable energy capacity were simulated in three scenarios. In these scenarios, the amount of electricity generated from the solar power plant, diesel generators and BESS varied in order to analyse the effects on emissions and COEG. The analysis displayed that an increased capacity of solar power installed, both with the current size of the BESS capacity, and with an increased BESS capacity, resulted in lower COEG and emissions. It also showed that usage of less installed solar power capacity and increased usage of diesel generators would reduce CO2 emission sper year compared to using the local grid. However, with the current price of diesel fuel and electricity from the local grid, it would result in a higher COEG. / Elektrifiering av landsbygden fungerar som ett verktyg för att nå flera av FN:s mål för hållbarutveckling. Däremot uppstår utmaningar relaterade till ökad tillgång till elektricitet, som involverar både finansiella, informationsmässiga, tekniska och regulatoriska faktorer. Ett ytterligare problem som elektrifiering medför är de potentiella klimateffekter som ökad elproduktion orsakar. För att minimera utsläpp och energiförluster är användning av förnybara energikällor samt ökad decentraliserad elproduktion en möjlig lösning. Microgrids möjliggör båda dessa delar och fungerar därför som en utmärkt lösning för att på ett hållbart sätt möta den ökade efterfrågan på el. Huvudsyftet med denna studie är därför att undersöka microgrids potential att på ett hållbart sätt bidra till ökad tillgång till elektricitet. Studien fokuserar på elsituationen i Thailand. Litteraturstudien täcker landets politiska strategier för landsbygdens elektrifiering och implementering av förnybara energikällor i det thailändska elkraftsystemet, samt hur landet för närvarande utvecklas enligt dessa strategier. Fallstudien består av en kostnads- och utsläppsanalys relaterad till ett microgridpilotprojekt i norra Thailand. Provincial Electricity Authority (PEA) i Thailand initierade och byggde microgridprojektet Maesariang Microgrid i Mae Sariang-distriktet, i den norra provinsen MaeHong Son. Syftet med microgridprojektet var att förbättra tillförlitligheten och kvaliteten på elektriciteten som levereras till Mae Sariang-distriktet. Microgridet består av en solpark, ett vattenkraftverk, dieselgeneratorer och ett batterienergilagringssystem. Resultaten från fallstudien visar att implementeringen av microgridet i Mae Sariang, förutom strömtillförlitlighet och kvalitet, har lett till både minskad kostnad för elproduktion med 3 procent och CO2-utsläpp med 11 procent. Vidare har utsläppen per genererad elenhet minskat från 380 kg CO2 per MWh till 340 kg CO2 per MWh. Genom att använda en systemmodell som omfattar det nuvarande microgridet i Mae Sariang, simulerades tre alternativa microgridsammansättningar med olika andelar installerad förnybar energikapacitet i tre scenarion. I dessa scenarion varierar mängden el som genereras från solparken, dieselgeneratorer och batteriet för att analysera hur utsläpp och kostnad förelproduktion påverkas. Analysen visade att en ökad kapacitet av installerad solenergi, både med nuvarande storlek på batteriet, och med en ökad batterikapacitet, resulterade i lägre kostnader för elektricitet och utsläpp. Den visade också att användning av mindre installerad solenergikapacitet och ökad användning av dieselgeneratorer skulle minska CO2-utsläppen per år jämfört med att använda det lokala nätet. Dock skulle det resultera i högre kostnader för elektricitet med det nuvarande priset på dieselbränsle och el från det lokala nätet.

Today’s electric excavators uses standard hydraulics to control external tools. To increase the degree of freedom the excavator is equipped with a tiltrotator placed between arm and bucket. The combination of electronics and hydraulics proves to be less beneficial for the final operating time and shall thereby, if possible, be replaced with other options.  The study is conducted in purpose to present combinations of motors and drives which can apply and resist necessary forces. The solution replaces today’s hydraulic motor and worm drive powered by a hydraulic system existing of pump, hoses, and valves.  The transition can initially be motivated out of earlier studies which shows that electrification of hydraulic components has the potential to reduce the energy usage. In combination with this, excavators with an electric driveline becomes more and more popular which places increasing requirements on underlying systems.  Conduction of this work uses an analysis of earlier studies where identified components are evaluated out of geometric and characteristic features. Apart from this an analysis of strength in combination with required dimensions is made. The final solutions are compared with a hydraulic system to define potential energy savings.  Results shows two suitable solutions, one based on a DC motor and the other based on the patented technique for PMSM; the motors are combined with cycloid drives in two and one stages. The results shows that the solutions can be designed to apply necessary force as well as withstand external ones.

I Scanias elektriska och hybriddrivna fordon används elmotorer av typen P80 och P160. Båda motorer använder samma kontaktbrygga för elektrisk kontaktering mellan elmaskinen i motor-huset och växelriktaren. En tidigare utredning har kommit fram till att noggrannare analyser bör göras kring kontaktbryggans tillförlitlighet. I fokus står skruvförbanden som säkerställer kontakten mellan ingående kablar och elmotor. I det här arbetet görs teoretiska och empiriska undersökningar av de statiska förhållandena i dessa skruvförband och hur de påverkas av temperaturändringar. Undersökningen möjliggör tydliga slutsatser, och visar att temperaturvariation orsakar sättning och temporära förändringar av klämkraften. Förbanden är mycket känsliga för sättning och tem-peraturändringar. Det kan därför inte uteslutas att klämkrafterna i drift enligt kravspecifikation hamnar utanför gränserna av 1 till 10 kN. I ett sådant fall skulle kontaktbryggans strömöverförande funktion inte längre vara garanterad.Baserat på undersökningen tas fram sex alternativa koncept för kontaktbryggan. Två av dem är små förbättringar av den nuvarande lösningen, och fyra innebär nykonstruktioner med strömske-nor eller fjäderkontakter. Efter jämförelse av alternativen med den nuvarande lösningen rekom-menderas en nykonstruktion av kontaktbryggan med ingjutna strömskenor. Därutöver föreslås standardisering av materialegenskaper för koppar och mässing i skruvsammanhang. För en kort-siktig lösning bör mer väldefinierade åtdragningsmetoder komma till användning vid montering av skruvar på elkontakter. Detta kommer att minska klämkraftens spridning efter montering. / In Scania's electric and hybrid vehicles, P80 and P160 electric motors are used. Both motors use the same contact bridge for electrical connection between the electric machine in the engine housing and the inverter. A previous investigation has concluded that more accurate analyses should be made regarding the dependability of the contact bridge. The focus is on the screw connections that ensure the connection between the input cables and the electric motor. In this work, theoretical and empirical investigations of the static conditions in these screw connections are made and how they are affected by temperature changes. The examination allows clear conclusions, showing that temperature variation causes embedment and temporary changes in clamping force. The screw connections are very sensitive to embedment and temperature changes. Therefore, it cannot be precluded that the clamping forces end up outside the limits of 1 to 10 kN, when in operation according to the requirements specification. In such a case, the contact bridge's conducting function would no longer be guaranteed.Based on the examination, six alternative concepts for the contact bridge are presented. Two of them are small improvements to the current solution, and four involve new constructions with busbars or spring contacts. After comparing the alternatives with the current solution, a new construction of the connector bridge with overmolded busbars is recommended. In addition, the standardization of material properties for copper and brass in screw contexts is proposed. For a short-term solution, more well-defined tightening methods should be used when installing screws on electrical contacts. This is going to reduce the spread of clamping force after assembly.