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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Mine haulage study concerning trolly-truck system feasibility

Carlson, John Norman, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Electric-road freight transport, Arlanda-Rosersberg logistic flow and environmental analysis.

Wang, Qiuchen, Mompo, Santiago January 2014 (has links)
The expected economic and social growth, joint with the increase on the demand of services and goods that this will cause, will become an environmental problem (emissions and noise) as well as a logistical problem (congestion) that needs to be solved. The transport sector has to reduce drastically the use of fossil fuels and Sweden’s goal is to achieve a fossil independent vehicle fleet by 2030. It is expected that 2/3 of the traffic volume of trucks in Sweden will be performed along electrified roads. The most efficient way to achieve this is to use electricity and now that the technology to power trucks without the need of huge batteries has been tested and approved, is time to develop the infrastructure needed and study its impact in transportation and logistics. An electric road is planned to be operative around 2020 from Rosersberg logistics hub to Arlanda airport cargo city. The objective is to transfer goods from the logistic area to the freight terminal by the use of electric trucks. It will optimize the transit of logistics flow in the area, reduce emissions and release the traffic pressures on E4 at the same time. Arlanda airport used to have a restriction on the emission rate of all the companies operating inside Arlanda, the emissions of the trucks that drive the cargo outside Arlanda was also taken into account. This means that in order to be below the maximum levels, the high ground transport emissions limited the number of planes that could fly. Affecting therefore the capacity of handling bigger volumes and passengers. So in order to prevent this situation from happening again in the future (more environmental restrictions will appear) the best solution for all the parts involved is to give priority to sustainability in transport planning. The aim of this project is to come up with conclusions and forecasts of the whole transportation network according to the logistics needs, by analysing the economic, environmental and logistic impacts of using the El-road. The result expected is to provide a clearer overall picture of the logistic flows between Rosersberg, Arlanda Airport, Gavle container and nearby locations, such as Stockholm or Uppsala. As well as analyse the possible scenarios that might develop once the El-road is operating. Due to the nature of our data we decided to use qualitative and subjective methods rather than quantitative ones. AHP (Analytic Hierarchy Process, Saaty 1970), will enable us to derive ratio scales from paired comparisons by defining the different criteria (cost, time, operations and sustainability) and assigning values to their respective sub criteria. These values will be assigned by each of the companies working inside Arlanda, since the goal is to define the best possible scenario for them in the future. The other method we will use is the decision tree analysis, this model of decisions and possible consequences that can occur will show a graph of all the variables that must be taken into account while defining the issues that will lead to one scenario or another. We consider it the best method to analyse and show how many facts can affect the final scenario outcome of this project.
3

Platoon Coordination of Electric Trucks at a Charging Station

Björklund, Elin, Lindstedt, Ebba January 2022 (has links)
Electric trucks and platooning technology are expected to be part of the transportation system in the near future. Therefore, it is important to develop platoon coordination strategies and study the potential of platooning for when trucks are electric. In this paper, we study the platoon coordination problem at a single charging station where electric trucks can charge while they wait for other trucks to form platoons with.We assume all trucks to have identical routes after the charging station. The objective is to maximize the total reward of all trucks, including the platooning profit and cost of waiting.Moreover, the trucks have waiting time constraints to respect their mission deadlines and charging time constraints to make sure they can travel between the hub and destination without running out of battery. The energy consumption is decreased when driving as a follower truck in a platoon, which decreases the minimum charging time for the truck. We formulate the platoon coordination problem of electric trucks as a linear integer optimization problem. To evaluate the method, it was compared to a simpler coordination method. The savings from platooning with electric vehicles, using both coordination methods, were also compared to platooning with diesel trucks. The results showed that platooning with electric vehicles can save up to 10% of the driving cost and therefore have significant economic benefits. It was also shown that the method has an acceptable computational efficiency for real-time coordination. / Inom en snar framtid förväntas elektriska lastbilar och platooning vara en del av transportsystemet. Det är därför viktigt att utveckla strategier för platoonkoordinering och undersöka potentialen av platooning med elektriska lastbilar. I det här pappret studerar vi ett platoonkoordineringsproblem med en gemensam startpunkt och en gemensam slutpunkt för alla lastbilar. Startpunkten är en laddningsstation där lastbilarna kan kombinera laddning med att vänta in andra lastbilar att forma platooner med. Lastbilarna i systemet har även samma rutt mellan de två punkterna. Målet är att maximera den totala vinsten för alla lastbilar, med hänsyn till både platooningvinsten och kostnaden för att vänta. Utöver det har lastbilarna begränsad väntetid för att hålla sina deadlines. Vi behöver även ta hänsyn till lastbilarnas laddningstider då de behöver ha tillräckligt med laddning för att åka hela resan från startpunkt till slutdestination. Energikonsumtionen minskar när en lastbil åker som följare vilket minskar den minimala laddningstiden som behövs för att åka hela sträckan. Vi formulerar koordineringsproblemet med elektriska lastbilar som ett linjärt heltalsoptimeringsproblem. För att utvärdera metoden jämfördes den med en enklare koorineringsmetod. Besparingarna från platooning med elektriska lastbilar, med båda koordineringsmetoderna, jämfördes även med platooning med diesellastbilar. Resultatet visade att platooning med ellastbilar kan spara upp till 10% av körkostnaderna och har därför betydande ekonomiska fördelar. Det visades också att metoden har en acceptabel beräkningseffektivitet för koordinering i realtid. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm
4

The environmental impact assessment of manual and automatic truck types

Maithani, Abhinav January 2020 (has links)
Trucks are used to transport goods and services using road transportation. Emissions from the transportation industry are rising with every passing year. The Swedish government said in a report in 2009 that they are working to reduce 70% of the greenhouse gas emissions by 2030 to build a pathway for sustainable transportation (Allerup, 2019). New technologies in the field of transportation are coming to the market every year. It is important to evaluate the impacts from these technologies to support the 2030 agenda of Swedish government. Life cycle analysis of trucks can give valuable insight into the hotspots from different life cycle stages. To provide a comprehensive overview of the emissions from different types of heavy duty trucks namely Internal combustion engine trucks (Manual and driverless) and electric trucks (manual and driverless) a life cycle assessment is carried out.  From the comprehensive evaluation of results, following questions are answered. [1] Global warming potential from different types of heavy duty trucks; [2] Impacts from the new automation technology on climate change; [3] Environmental hotspots evaluation of the different truck types; and [4] Impacts of using different fuel types on the Global warming potential. Overall, the life cycle assessment can help the decision makers for taking decisions in order to fulfill the agenda 2030 of the Swedish government but still further research is needed to be done to exactly find out the emissions level of new automation technologies. / Lastbilar används för att transportera varor och tjänster med vägtransport. Utsläppen från transportbranschen ökar för varje år som går. Den svenska regeringen sa i en rapport 2009 att de arbetar för att minska 70% av växthusgasutsläppen till 2030 för att bygga en väg för hållbara transporter. Ny teknik inom transportområdet kommer till marknaden varje år. Det är viktigt att utvärdera effekterna av denna teknik för att stödja 2030-agendan för den svenska regeringen. Livscykelanalys av lastbilar kan ge värdefull inblick i hotspots från olika livscykelsteg. För att ge en omfattande översikt över utsläppen från olika typer av tunga lastbilar, nämligen IC-motor bilar (manuella och förarlösa) och elektriska lastbilar (manuella och förarlösa) genomförs en livscykelbedömning.  Från den omfattande utvärderingen av resultaten besvaras följande frågor. [1] Global uppvärmningspotential från olika typer av tunga lastbilar; [2] Effekter från den nya automatiseringstekniker på klimatförändringar. [3] Miljö Hotspots utvärdering av olika lastbilstyper; och [4] Effekter av användning av olika bränsletyper på den globala uppvärmning potentialen. Sammantaget kan livscykelbedömningen hjälpa beslutsfattarna att fatta beslut för att uppfylla den svenska regeringens dagordning 2030, men ytterligare forskning behövs för att exakt ta reda på utsläppsnivån för ny automatiseringsteknik.  Resultaten av studien visar att elbilen har lägre GWP-utsläpp än IC-motor bilarna. Den förarlösa automatiseringstekniker har 1,37% av de totala GWP-utsläppen när det gäller IC-motor bilar. Medan för elektriska lastbilar bidrar förarlös automatiseringsteknik upp till 12% av de totala utsläppen av elbil.
5

Alternative Drivetrain for Future Freight Trucks

Tsamos, Athanasios January 2020 (has links)
Presently, heavy-duty trucks are responsible for approximately 25% of global CO2 emissions. Although the world seems to incline towards the transport sector's electrification, the electrification of long-range freight trucks is profoundly challenging. The dominant disincentives are the required infrastructure, cost/size of batteries, limited mileage, and long charging sessions. However, despite the efforts to reduce emissions, current trends indicate that these continue to rise, mostly because of the continually increasing freight transit. Regional economies are heavily dependent on the latter. Thus, the imminent depletion of fossil fuels and the emerging environmental issues are disquieting aspects for the sustainability of this crucial sector. This thesis focuses on the possible alternative powertrain/drivetrain solutions for heavy-duty, long-range freight trucks in conjunction with sustainable energy carriers for the transportation sector overall. In terms of viable fuelling alternatives, the following are being reviewed: Electric Power, Bio-Fuels, and Synthetic Fuels, along with their current status, advantages, disadvantages and future prospects. In terms of powertrain/drivetrain alternatives, the following are being theoretically and critically evaluated and compared against a direct drive conventional Diesel engine truck (25.2% wheel efficiency): Battery Electric, Electric powered with overhead cables or underground conductive coils, combined Gas Turbine/Stirling Engine Hybrid Electric in series, combined Diesel engine/Stirling engine Hybrid Electric in series, and Diesel engine Hybrid Electric in series.  It is concluded that the best scenario for future freight trucks, is the use of an electric drivetrain/powertrain in conjunction with overhead powering cables along the highways. However, due to uncertainties in the universal realization of such infrastructure, to ensure uninterrupted transportation of goods, a plausible transitional solution could be the use of a Diesel engine/Stirling engine Hybrid Electric in series technology. This could reduce emissions/consumption by a factor of 2.4 (60% wheel efficiency). For the case of Gas turbine/Stirling engine and Diesel engine (both) Hybrid Electric in-series arrangements, this factor drops to 1.7 and 1.4 (42.9% and 34.3% wheel efficiency), respectively. Furthermore, this can be a clean and sustainable solution if biofuels are employed as the prime energy carriers. Such an approach is future-proof for use with overhead cables, since the suggested powertrain is electric, rendering a freight truck as a very versatile heavy-duty, long-range vehicle. Electro-fuels are not considered as a viable option due to their inefficient formulation, elevated costs, and problematic handling (Hydrogen).
6

Truck electrification : Trends and impacts on the energy system

NORDHAMMER, CAROLINE, GRANKVIST, JESSICA January 2021 (has links)
In line with the Paris agreement, Sweden has set up a national emission reduction target for the transport sector; to reduce the emissions by 70% by 2030, relative to levels in 2010. This entails that large shares of road transport will be electrified, including shares of the national truck fleet. In parallel with this, the Swedish transmission grid suffers from power capacity shortages, limiting the amount of electricity that can be distributed to a regional and local level, especially in urban areas, such as Stockholm. In line with this, the aim of this thesis is to investigate the trends of truck electrification in the Stockholm region and to assess its potential impact on the electrical grid based on truck operation characteristics. To achieve this, three objectives were set; to investigate truck fleet operators’ operations and view in relation to electrification, examine truck manufacturers' views on truck electrification and to analyse the truck electrification’s potential impact on the electrical grid in future scenarios. Quantitative and qualitative methods were used to fulfil the research objectives including interviews and casestudy modelling. The results from the interviews show that both manufacturers and truck fleet operators see the electrical grid and deployment of charging infrastructure, as well as the economy of the electric truck as the main barriers to overcome in relation to truck electrification. The truck manufacturers have taken on a leading role and are together with early adopters pushing the development forward. Nonetheless, they cannot create all the right conditions themselves, as for instance charging opportunities in relation to the electric grid is a complex problem. The industry agreed upon that city transports will be electrified first followed by regional transport and lastly long-distance transport. Furthermore, 2030 was identified as a key year for truck electrification. Finally, manufacturers and truck fleet operators urge the government to act and implement necessary measures to support the transition. The results from the case-study modelling show that lunchtime charging of city transport coincides with already critical hours for the electrical grid. Moreover, the afternoon charging of city, regional and long-distance transports generates a peak during the most critical hour around 6 PM, implying that it could entail challenges for an already congested grid. In line with this, proper night-time charging is considered as crucial both from an operational (in terms of minimising the daily stops) and grid point of view (in terms of avoiding grid congestion during critical hours). In addition, it is recommended to prioritise charging of long-distance transport during the day as they often are operative around-the-clock. Although this study resulted in general charging profiles, this gives a good indication on what impact the truck electrification might have on the electrical grid. Furthermore, it gives a general picture of how the electrification of trucks could play out in Stockholm, which can be applied in other urban areas in Sweden that are facing similar challenges. / I linje med Parisavtalet har Sverige satt upp nationella utsläpps reduktionsmål för transportsektorn; att reducera utsläppen med 70% till 2030, relativt nivåerna 2010. Detta medför att stora delar av transportsektorn kommer att elektrifieras, inklusive stora delar av den nationella lastbilsflottan. Parallellt med detta lider det svenska transmissionsnätet av kapacitetsbrist vilket begränsar mängden elektricitet som kan överföras till en regional och lokal nivå, speciellt i urbana områden såsom Stockholm. I linje med detta har syftet med denna studie varit att undersöka trender inom lastbils-elektrifiering i Stockholmsregionen och att utvärdera dess potentiella inverkan på elnätet baserat på lastbilars operativa mönster. För att uppnå detta sattes tre mål upp; att undersöka lastbils-operatörers verksamhets mönster och deras syn på elektrifiering, att undersöka lastbilstillverkares syn på elektrifiering och att analysera lastbils-elektrifieringens potentiella inverkan på energisystemet i framtida scenarier. Kvantitativa och kvalitativa metoder användes för att uppnå studiens mål inklusive; intervjuer och fallstudie modellering. Resultaten från intervjuerna visar att både lastbils-operatörer och tillverkare ser elnätet och utbredningen av laddinfrastruktur, såväl som totalekonomin av den elektriska lastbilen som de huvudsakliga barriärerna att överkomma vid en elektrifiering. Lastbilstillverkare har tagit en ledande roll och driver utvecklingen av elektriska lastbilar framåt med hjälp av så kallade early adopters. Däremot kan de inte skapa alla förutsättningar själva då till exempel laddnings möjligheter i relation till elnätet är en komplex fråga. Industrin är eniga om att city transporter kommer att elektrifieras först, följt av regionala och till sist fjärrtransporter. Vidare kunde 2030 identifieras som ett nyckelår för elektrifieringen. Slutligen uppmanar både tillverkare och lastbils operatörer regeringen att implementera nödvändiga åtgärder för att stötta och påskynda omställningen. Resultaten från modelleringen i fallstudien visar att lunch-laddning för city transporter sammanfaller med redan kritiska timmar för elnätet. Dessutom genererar eftermiddagsladdningen av city, regionala och fjärrtransporter, en effekttopp runt klockan 18 vilket skulle kunna medföra utmaningar för ett redan överbelastat elnät. I linje med detta anses natt-laddning vara avgörande både från en operativ synpunkt (i form av att minimera de dagliga stoppen) och från ett elnäts perspektiv (i form av att undvika överbelastning av nätet under redan kritiska timmar). Därtill, rekommenderas att fjärrtransporter prioriteras för dagtids-laddning då de ofta är operative dygnet runt. Trots att denna studie resulterade i generella ladd-profiler kan dessa ge en god indikation för vilken inverkan lastbils-elektrifieringen kan komma att ha på elnätet. Vidare, ger studien en generell bild över hur lastbils-elektrifieringen kan komma att se ut i Stockholmsregionen vilket kan tillämpas i andra urbana områden i Sverige som står inför liknande utmaningar.
7

Route Planning of Battery Electric Heavy-Duty Commercial Vehicles : Using Contraction Hierarchies and Mixed Integer Programming

Delborg, Olle, Insulander, Elias January 2023 (has links)
This thesis addresses route planning of Battery Electric Heavy-Duty Commercial Vehicles to enhance the reliability of electric vehicle transport. Collaborating with Scania, a Swedish truck manufacturing company, the goal is to develop a pipeline that uses open source data from OpenStreetMap and performs a modified Contraction Hierarchy in order to create a graph that can be used as input to a modified Vehicle Routing Problem formulation using Mixed Integer Programming. The input graph is preprocessed to support a Battery Electric Heavy-Duty Commercial Vehicle model in order to more accurately predict energy consumption. The challenges lie in balancing computational efficiency and electric vehicle characteristics. The implemented pipeline demonstrates success but initial tests show that a naive version of the pipeline, not implementing Contraction Hierarchies, can perform better. Several speedups can be made in order to improve the efficiency of the pipeline, the main being in programming in a more efficient programming language than Python. Further testing is needed for larger input graphs to assess performance accurately.
8

When is Electric Freight Cost Competitive? : Computational modeling and simulation of total cost of ownership for electric truck fleets / När är elektrisk varutransport kostnadskonkurrenskraftig? : Beräkningsmodellering och simulering av total ägandekostnad för elektriska lastbilsflottor

Zackrisson, Anton January 2023 (has links)
Battery electric trucks (BETs) offer environmental benefits in terms of reduced carbon emissions and enhanced energy efficiency but have been challenged with economic viability compared to conventional internal combustion engine trucks (ICETs) caused by substantial acquisition costs, limited charging infrastructure, and concerns regarding range and payload capacity.  Previous studies focus on TCO at the vehicle or policy level but overlook the system and firm-level impacts. Operational aspects like vehicle utilization, battery utilization, charging planning, and route optimization are often ignored, potentially underestimating electric freight cost-competitiveness.The research gap does not address the practical needs of fleet operators, especially in scenarios where charging infrastructure is lacking. There is therefore a need to consider the complex system level interactions, market dynamics, technology developments, and operational processes involved in freight shipping. By applying a decision-making under deep uncertainty (DMDU) framework, this study enables informed decisions in unpredictable scenarios, bridging the gap between strategic choices like battery capacity and operational optimization like route planning. This study identifies the most significant factors that affect the TCO of BET fleets and cost-competitiveness relative to ICET fleets, taking into account market-operational interfaces between unpredictable market dynamics and operational processes such as stochastic demand and feature selection from a strategic and operational perspective. 40 tonne truck-trailers for freight distribution networks with distances up to 250 km are considered in the study.  A TCO model of BET and ICET fleets was developed taking into account vehicle route optimization, vehicle selection, and vehicle utilization which was then programmatically iterated by sampling and simulating optimized vehicle routes for a total of 220 224 iterations. The parameter space was screened and reduced with Feature Scoring using Extra Trees approximation of 1st order Sobol Indices. The reduced parameter space was then sampled using Sobol sampling to conduct a Sobol Global Variance decomposition Analysis of TCO, TCO delta, and service level in order to identify the most significant factors affecting BET fleet TCO and cost-competitiveness.To identify cost-competitive scenarios, the Patient Rule Induction Method (PRIM) was used to identify parameter sub spaces to determine scenarios where BET fleets have a lower TCO than ICET fleets. Further visual analysis was done using linear and polynomial regression and kernel density estimation. The analysis shows that both TCO and cost-competitiveness of BETs are primarily affected by shipment demand, distance between distribution center and delivery sites, and battery size, and that a trade-off is made between cost-competitiveness and service level. The results show that cost-competitiveness of electric freight scales with demand, with larger fleets being better able to optimize routing and shipment allocation; balancing the shipment demand to minimize charging times that otherwise would make the fleet less competitive than their fossil-fuel counterparts. This, paired together with higher degrees of vehicle utilization and appropriate battery sizing, allow for electric freight to be cost-competitive even for long-haul distances up to 250 km.  Furthermore, optimization of the Electric Vehicle Routing Problem (E-VRP) with shifts and time windows is shown to have a highly significant effect when minimizing TCO on a fleet level, with the vast majority of optimal ICET routes not being optimal for BETs.The benefits of E-VRP optimization scales with demand and fleet size, indicating that large-scale electrification is required to make BETs cost-competitive.Electrification of road freight is therefore highly contingent on effective route planning and charging scheduling with E-VRP optimization in order to be cost-competitive, which has not been considered in previous literature. Thus previous literature have therefore likely underestimated the cost-competitiveness of electric freight, particularly at medium-long haul distances. / Battery electric trucks (BETs), även kända som batterielektriska lastbilar, erbjuder miljömässiga fördelar genom minskade koldioxidutsläpp och förbättrad energieffektivitet. Men de har utmanats när det kommer till ekonomisk konkurrenskraft jämfört med konventionella lastbilar med förbränningsmotor (ICETs) på grund av höga inköpskostnader, begränsad laddinfrastruktur och oro över räckvidd och lastkapacitet. Tidigare studier har fokuserat på TCO (totala ägandekostnader) på fordon- eller policynivå men har inte betraktat TCO på nätverksnivå och från det enskilda företagets perspektiv. Operativa aspekter som fordonssutnyttjande, batteriutnyttjande, laddningsplanering och ruttoptimisering ignoreras ofta, vilket potentiellt leder till en underskattning av elektrisk frakts kostnadskonkurrenskraft. Forskningsluckan tar inte upp de praktiska behoven hos fordonsflottoperatörer, särskilt i scenarier där laddinfrastrukturen är bristfällig. Det finns därför ett behov av att granska komplexa systemnivåinteraktioner, marknadens dynamik, teknikutveckling och operativa processer som är involverade i godstransport. Genom att tillämpa \textit{decision-making under deep uncertainty} (DMDU) möjliggör denna studie informerade beslut i scenarier präglade av osäkerhet och studerar interaktionseffecter mellan strategiska val som batterikapacitet och operativ optimering som t.ex.\ ruttplanering. Denna studie identifierar de mest betydande faktorer som påverkar TCO för BET-flottor och deras kostnadskonkurrenskraft jämfört med ICET-flottor, med beaktande av gränssnitten mellan marknadsdynamik och operativa processer såsom stokastisk efterfrågan och urval av funktioner ur såväl strategisk som operativ synvinkel. 40-ton lastbilssläp för nätverk med avstånd upp till 250 km beaktas inom omfånget för studien. En TCO-modell för BET- och ICET-flottor utvecklades med hänsyn till ruttoptimering, fordonsval och fordonsutnyttjande, vilket sedan programmässigt itererades genom provtagning och simulering av optimerade fordonsrutter för sammanlagt 220 224 iterationer. Parameterrummet granskades och minskades med hjälp av funktionsskattning med hjälp av Extra Trees-approximation av Sobol-indices av första ordningen. Det reducerade parameterrummet provtogs sedan med Sobol-provtagningsmetod för att genomföra en global variansdekomponering av TCO, TCO-delta och servicenivå för att identifiera de mest betydande faktorerna som påverkar BET-flottans TCO och kostnadskonkurrenskraft. För att identifiera kostnadskonkurrenskraftiga scenarier användes Patient Rule Induction Method (PRIM) för att identifiera parametrarum som visar scenarier där BET-flottor har lägre TCO än ICET-flottor. Vidare utfördes visuell analys med linjär och polynomisk regression samt kärnskattning. Analysen visar at kostnadskonkurrenskraft för tunga elektriska fordon primärt påverkas av efterfrågan, köravstånder och batteristorlek, och att det görs en avvägning mellan kostnadskonkurrenskraft och servicenivå. Resultaten visar at kostnadskonkurrenskraft ökar i takt med efterfrågan, då större flottor kan mer fördelaktigt optimera rutter och allokering av leveranser till varje fordon genom att transportefterfrågan balanseras sådan att tiden för laddning minimeras, vilket hade annars gjort de elektriska flottorna mindre konkurrenskraftiga gentemot fossildrivna flottor av tunga fordon. Detta i samband med högre utnyttjandegrad av fordonen och val av rätt batteristorlek gjör att elektrisk godstransport kan vara kostnadskonkurrenskraftig även vid längre körsträckor upp till 250 km. Vidare visar ruttoptimering för BETs (E-VRP) sig vara av stor betydelse när det gäller att minimera TCO på flottnivå, medan majoriteten av optimala ICET-rutter inte är optimala för BETs.Fördelarna med E-VRP optimering skalar med ökande efterfrågan och flottstorlek, vilket tyder på att storskalig elektrifiering behövs för att göra BETs kostnadskonkurrenskraftigaElektrifiering av godstransport är därför starkt beroende av effektiv rutt- och laddningsplanering med E-VRP-optimering. Tidigare litteratur har sannolikt underskattat kostnadskonkurrenskraften för elektrisk godstransport, särskilt vid medellånga och långa transportavstånd.
9

Evaluating the potential of truck electrification and its implementation from user and agency perspectives

Theodora Konstantinou (5930705) 27 July 2022 (has links)
<p>  </p> <p>The trucking industry seems to be resistant to electrification, even though truck electrification can lead to large societal as well as user benefits. This dissertation develops a framework to inform policy making and enhance electric vehicle (EV) preparedness in the trucking industry through the study of two interrelated elements: (a) the adoption of electric trucks and (b) the appropriate implementation of electric truck technology. These two elements cover the user perspective, which is not adequately studied, and the agency perspective, which is pivotal in the decision-making process. Specifically, this study addressed the following research questions: (i) which factors affect the purchase decisions of truck fleet managers or owners for electric trucks? (ii) what is the ranking of and interrelationships between the barriers to the adoption of electric trucks? (iii) which location criteria should be considered for the strategic implementation of dynamic wireless charging (DWC) in a freight transportation network and where should this technology be located based on these criteria, and (iv) what is the impact of electric truck adoption on highway revenue and potential of alternative funding mechanisms to recover the revenue loss?</p> <p>For the adoption of electric trucks, a stated preference survey was designed and distributed online to truck fleet managers/owners in the U.S., gathering 200 completed responses. Statistical and multi-criteria decision-making approaches were employed to identify the factors that affect the purchase intentions of truck fleet managers and explore the barriers to electric truck adoption. The results showed that the purchase intentions of truck fleet managers are affected by trucking firm and truck fleet characteristics, behavioral factors/opinions regarding electric trucks, and awareness of innovative charging technologies. Furthermore, electric truck adoption would be accelerated if stakeholders focused on the barriers related to the business model, product availability, and charging time. Additionally, electric truck adopters and non-adopters may not be viewed as one homogenous group, since differences were found in the ranking and interrelationships of barriers to electric truck adoption between these two groups. </p> <p>The implementation of electric truck technology was examined based on the truck fleet managers’ survey, secondary data sources and the case of Indiana, U.S. A multi-criteria decision-making spatial approach was proposed to identify the candidate locations for the deployment of DWC. It was concluded that the most suitable locations for DWC lanes were on interstates, near airports and ports and away from EV charging stations. A data-driven framework was also developed to quantify the impact of electric truck adoption and estimate the optimal fee for each truck to recover the revenue loss. Using the market penetration levels estimated based on the survey data collected, the average annual fuel tax revenue loss for Indiana was approximately $349M. To maintain the same tax revenue per vehicle, annual fees ranging from $969 (in 2021) to $1,243 (in 2035) for single-unit trucks and $6,192 to $7,321 for combination trucks would be needed. To address public relations problems of EV fee implementation, this study also discussed alternative mitigation measures: a vehicle-miles-traveled fee and a pay-as-you-charge fee.</p> <p>In summary, this dissertation contributes to the body of literature by providing significant insights regarding the perspectives of truck fleet managers for electric trucks as well as a comprehensive list of all the location criteria for DWC. The proposed frameworks and study findings can be used by policymakers and other major stakeholders of the EV ecosystem to frame certain strategies to accelerate electric truck adoption, identify the most suitable locations for charging infrastructure, better understand the impact of electric trucks on the highway revenue, and provide the groundwork for developing EV roadmaps.</p>
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Development of heat recovery solution for heavy duty truck cabs to improve energy efficiency. / Utveckling av värmeåtervinningslösning för tunga lastbilshytter för att förbättra energieffektiviteten.

Aurelio, Exekiel, Acharya Rathnakar, Rahul January 2022 (has links)
The recent climate actions to reduce greenhouse gas (GHG) emissions have set the stage for decarbonizing the transportation sector through electrification, which has led to a surge in the deployment of battery electric vehicles (BEV). Trucks are no exception, which has led automakers to shift their focus toward producing Battery Electric Trucks (BET). While tail-pipe emissions are reduced drastically, certain aspects of BET prevent its widespread deployment, prominent of which is the range anxiety. The range of a BET is heavily impacted in cold weather as energy from traction batteries is also used to warm the battery pack and cabin, where 70% of cabin airflow at minimum is continually expelled through exhaust vents for proper ventilation. In this study, three heat recovery techniques were investigated with the objective of harnessing the waste heat from evacuating cabin air to reduce the heating energy consumption in a BET. One proposed technique employs the use of an air-to-air heat recovery system (AAHRS). Baseline experiments were conducted on a SCANIA test truck for benchmarking and to gather data on the performance of the installed HVAC system, which aided the prototyping stage of basic engineering design to ensure it is operable and safe. The prototype was modelled in CATIA, then fabricated and fitted to the test-truck. Validation experiments were done to evaluate the energy savings from the prototype in a climate chamber at various ambient temperature and fan speed settings. The study found a 20-53% reduction in the heat dissipated by the coolant with the implementation of AAHRS, which is beneficial in reducing the energy that need to be replenished by electric batteries for a BET. In contrast, the electrical power consumption increased 1.7-3.3 times higher than the baseline due to the additional power-consuming components, such as the exhaust blower and heat wheel motor. Moreover, the preheating effect from the heat wheel operation enabled the increase of HVAC air intake temperature by 7-28°C from ambient levels. Overall, the energy savings from integrating the AAHRS prototype was about 19-47% considering the coolant heat was produced from an electric heater as was simulated in the tests, whereas the range was estimated to reduce by17-39% if an automotive heat pump would instead deliver the heat into the cab heater core. Two other presented techniques operate on air-to-liquid heat recovery system (ALHRS), whereby each is envisioned to be coupled separately to a heat pump assisted integrated thermal management system (ITMS). One scheme recovers heat from the evacuating cabin air to raise the chiller coolant inlet temperature, whereas the other scheme proposes to adopt a multi-evaporation process in the concept liquid-cooled heat pump, wherein the evacuating cabin air serves as the direct heat source for the higher temperature-chiller. The two schemes were initially evaluated via vapor compression system performance analysis to have the potential to increase the condensation heat and condenser coolant outlet temperature with simultaneous increase in the coefficient of performance, which is beneficial in terms of available heat that can be dissipated into the downstream battery cold plates and cab heater core. As initial step towards assessment of the energy-saving potential of proposed ALHRS solutions, a simulation model of an adopted baseline ITMS concept was developed in this study using Engineering Equation Solver (EES) software, which then was validated against internal bench test results for a mock-up ITMS model. Results of initial validation test indicated an absolute error between the simulation outputs and bench test results of 8-14% for condensation heat, while it was below 7% for all the other relevant performance parameters. / De senaste klimatåtgärderna för att minska utsläppen av växthusgaser (GHG) har satt scenen för att minska koldioxidutsläppen inom transportsektorn genom elektrifiering, vilket har lett till en kraftig ökning av utbyggnaden av batterielektriska fordon (BEV). Lastbilar är inget undantag, vilket har fått biltillverkare att flytta fokus mot att producera batterielektriska lastbilar (BET). Medan utsläppen från avgasröret minskar drastiskt, förhindrar vissa aspekter av BET dess utbredda distribution, varav framträdande är räckviddsångesten. Räckvidden för en BET påverkas kraftigt i kallt väder eftersom energi från dragbatterier också används för att värma batteripaketet och kabinen, där minst 70% av kabinluftflödet kontinuerligt släpps ut genom avgasventiler för korrekt ventilation. I denna studie undersöktes tre värmeåtervinningstekniker med målet att utnyttja spillvärmen från evakuering av kabinluft för att minska värmeenergiförbrukning i en BET. En föreslagen teknik använder användning av ett luft-till-luft-värmeåtervinningssystem (AAHRS). Baslinjeexperiment utfördes på en SCANIA-testbil för benchmarking och för att samla in data om prestandan hos det installerade HVAC-systemet, vilket hjälpte prototypstadiet för grundläggande teknisk design för att säkerställa att det är funktionsdugligt och säkert. Prototypen modellerades i CATIA, tillverkades sedan och monterades på testbilen. Valideringsexperiment utfördes för att utvärdera energibesparingarna från prototypen i en klimatkammare under olika inställningar för omgivningstemperatur och fläkthastighet. Studien fann en 20-53% minskning av värmebelastningen med implementeringen av AAHRS, vilket är fördelaktigt för att minska energin som behöver fyllas på av elektriska batterier för en BET. Däremot ökade den elektriska strömförbrukningen 1.7-3.3 gånger högre än baslinjen på grund av ytterligare strömförbrukande komponenter, såsom avgasfläkten och värmehjulsmotorn. Dessutom möjliggjorde förvärmningseffekten från värmehjulsdrift ökningen av HVAC-luftintagstemperaturen med 7-28°C från omgivande nivåer. Sammantaget var energibesparingarna från att integrera AAHRS-prototypen cirka 19-47% med tanke på att kylvätskevärmen producerades från elektrisk värmare som simulerades i experimenten, medan detta intervall uppskattades minska ner till 17-39% om en bilvärmepump istället skulle leverera värmen till hyttvärmarkärnan. Två andra presenterade tekniker fungerar på luft-till-vätska värmeåtervinningssystem (ALHRS), där var och en är tänkt att kopplas separat till ett värmepumpassisterat integrerat värmehanteringssystem (ITMS). Det ena schemat återvinner värme från den evakuerande kabinluften för att höja kylvätskeinloppstemperaturen, medan det andra schemat föreslår att man antar en multiindunstningsprocess i konceptet vätskekyld värmepump, där den evakuerande kabinluften fungerar som den direkta värmekällan för kylaggregatet med högre temperatur. De två scheman utvärderades initialt via ångkompressionssystemets prestandaanalys för att ha potential att öka kondensationsvärmen och kondensorns kylvätskeutloppstemperatur med samtidig ökning av prestandakoefficienten, vilket är fördelaktigt när det gäller tillgänglig värme som kan avledas i nedströms batteriets kylplattor och hyttvärmarens kärna. Som ett första steg mot en bedömning av energibesparingspotentialen hos föreslagna ALHRS-lösningar utvecklades en simuleringsmodell av ett antaget baslinje-ITMS-koncept i denna studie med hjälp av Engineering Equation Solver (EES) -programvara, som sedan validerades mot interna bänktestresultat för en mock-up ITMS-modell. Resultaten av det inledande valideringstestet indikerade ett absolut fel mellan simuleringsutgångarna och provbänksresultaten på 8–14% för kondensationsvärme, medan det var under 7 % för alla andra relevanta prestandaparametrar.

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