Electric Road Systems

(1)

Electric Road Systems

A feasibility study investigating a possible future of road transportation

Archit Singh

Master of Science Thesis EGI_2016-090 MSC KTH Sustainable Energy Engineering

Energy and Environment SE-100 44 STOCKHOLM

(2)

i

Master of Science Thesis EGI_2016-090 MSC

Electric Road Systems

A feasibility study investigating a possible future of road transportation

Archit Singh

Approved

2016-10-10

Examiner

Hatef Madani

Supervisor

Björn Hasselgren

Company Supervisor

Gunnar Asplund

Contact person

Björn Hasselgren

Abstract

The transportation sector is a vital part of today’s society and accounts for 20 % of our global total energy consumption. It is also one of the most greenhouse gas emission intensive sectors as almost 95 % of its energy originates from petroleum-based fuels. Due to the possible harmful nature of greenhouse gases, there is a need for a transition to more sustainable transportation alternatives. A possible alternative to the conventional petroleum-based road transportation is implementation of Electric Road Systems (ERS) in combination with electric vehicles (EVs). ERS are systems that enable dynamic power transfer to the EV's from the roads they are driving on. Consequently, by utilizing ERS in combination with EVs, both the cost and weight of the EV-batteries can be kept to a minimum and the requirement for stops for recharging can also be eliminated. This system further enables heavy vehicles to utilize battery solutions.

There are currently in principal three proven ERS technologies, namely, conductive power transfer through overhead lines, conductive power transfer from rails in the road and inductive power transfer through the road. The aim of this report is to evaluate and compare the potential of a full- scale implementation of these ERS technologies on a global and local (Sweden) level from predominantly, an economic and environmental perspective. Furthermore, the thesis also aims to explore how an expansion of ERS might look like until the year 2050 in Sweden using different scenarios. To answer these questions two main models (global and Swedish perspective) with accompanying submodels were produced in Excel.

The findings show that not all countries are viable for ERS from an economic standpoint, however, a large number of countries in the world do have good prospects for ERS implementation. Findings further indicated that small and/or developed countries are best suited for ERS implementation.

From an economic and environmental perspective the conductive road was found to be the most attractive ERS technology followed by overhead conductive and inductive road ERS technologies.

The expansion model developed demonstrates that a fast expansion and implementation of an ERS-based transportation sector is the best approach from an economical perspective where the conductive road technology results in largest cost savings until 2050.

(3)

ii

Examensarbete EGI_2016-090 MSC

Elektriska vägsystem

Genomförbarhetsstudie kring en möjlig framtid för vägstransport

Archit Singh

Godkänt

2016-10-10

Examinator

Hatef Madani

Handledare

Björn Hasselgren

Företagshandledare

Gunnar Asplund

Kontaktperson

Björn Hasselgren

Sammanfattning

Transportsektorn är en viktig del av dagens samhälle och står för 20% av den totala globala energiförbrukningen. Det är också en av de sektorer med mest växthusgasutsläpp, där nästan 95%

av energin härstammar från petroleumbaserade bränslen. På grund av växthusgasers potentiellt skadliga karaktär finns det ett behov för en övergång till mer hållbara transportmedel. En möjlig alternativ till den konventionella petroleumbaserade vägtransporten är implementering av elektriska vägsystem (ERS) i kombination med elfordon. Elektriska vägsystem är system som möjliggör dynamisk kraftöverföring till fordon från vägarna de kör på. Sålunda kan man genom att använda ERS i kombination med elbilar, minimera både kostnaden och vikten av batterierna samt även minska eller eliminera antalet stopp för omladdningar. Dessutom möjliggör detta system att även tunga fordon kan använda sig av batterilösningar.

Det finns för närvarande i princip tre beprövade ERS-tekniker, nämligen konduktiv kraftöverföring genom luftledningar, konduktiv kraftöverföring från räls i vägen och induktiv kraftöverföring genom vägen. Syftet med denna rapport är att utvärdera och jämföra potentialen för en fullskalig implementering av dessa ERS-teknik på en global och lokal (Sverige) nivå från, framförallt, ett ekonomiskt- och ekologiskt perspektiv. Rapporten syftar också till att undersöka, med hjälp av olika scenarier, hur en utbyggnad av ERS i Sverige skulle kunna se ut fram till år 2050. För att besvara dessa frågor producerades två huvudmodeller (global och lokal perspektiv) med kompletterande undermodeller i Excel.

De erhållna resultaten visar att ERS inte är lönsamt ur ett ekonomisk perspektiv i precis alla de undersökta länder, dock har ett stort antal länder i världen visat sig ha goda förutsättningar för ERS. Vidare visar resultaten att små och/eller utvecklade länder är bäst lämpade för ERS. Ur ett ekonomiskt- och ekologiskt perspektiv har konduktiv kraftöverföring från räls i väg tekniken visat sig vara den mest attraktiva, följt av konduktiv kraftöverföring genom luftledningar och induktiv kraftöverföring genom väg teknikerna. Expansionsmodellen som utvecklats visar att en snabb expansion och implementation av en ERS-baserad vägtransportsektor är det bästa alternativet, där tekniken för konduktiv kraftöverföring från räls i väg ger de största kostnadsbesparingar fram till 2050.

(4)

iii

Acknowledgements

I would like to express my upmost gratitude towards Elways and the department of Energy Technology at the Royal Institute of Technology for supporting and enabling this master thesis.

Especially, I would like to thank my supervisor Gunnar Asplund at Elways who gave me the inspiration for the master thesis and has since helped and supported me meticulously throughout the process. I am also very grateful toward my supervisor Björn Hasselgren at the Royal Institute of Technology for being a great mentor, contributing with insightful inputs and active engagement during my thesis. Furthermore, I would like to give a special thanks to my examiner Hatef Madani for his support and guidance during the thesis. Last but not least, I would like to extend my appreciation to my fellow students Mårten Lundqvist, Martin Isacsson and Eric Schmidt for their perceptive feedbacks while proof reading the thesis report.

Archit Singh Stockholm, August 2016

(5)

iv

List of Tables

Table 1. Yearly vehicle kilometer for all vehicles per road category during 2015. ... 49 Table 2. Yearly vehicle kilometer for heavy-duty trucks per road category during 2015. ... 49 Table 3. Expansion specifications for each scenario. ... 53 Table 4. Most important global results for each ERS technology in countries where the yearly savings are positive, assuming 2015 battery pricing. ... 55 Table 5. Most important global results for each ERS technology in countries where the yearly savings are positive, assuming future battery pricing. ... 55 Table 6. The cost difference in percent between the two cases for all 184 countries assuming 2015 battery pricing. ... 59 Table 7. The cost difference in percent between the two cases for all 184 countries assuming future battery pricing. ... 59 Table 8. Number of countries where the ERS solution is cheaper and the cost difference between the two cases assuming 2015 battery pricing. ... 59 Table 9. Number of countries where the ERS solution is cheaper and the cost difference between the two cases assuming future battery pricing. ... 60 Table 10. The most important results obtained for the three ERS technologies in Sweden assuming 2015 battery pricing. ... 61 Table 11. The most important results obtained for the three ERS technologies in Sweden assuming future battery pricing. ... 61 Table 12. The cost difference between the two cases for the two examined ERS technologies assuming 2015 battery pricing. ... 62 Table 13. The cost difference between the two cases for the two examined ERS technologies assuming future battery pricing. ... 62 Table 14. The pros and cons of each technology attained in the study from an economic, environmental and aesthetic perspective. ... 78 Table 15. Countries where the yearly savings from an ERS based transportation system are positive using the current battery price ((Conductive Road Case).. ... 91 Table 16. Countries where the yearly savings from an ERS based transportation system are positive using the future battery cost (Conductive Road Case). ... 94 Table 17. A list with countries where the ERS plus battery combination is cheaper than a pure battery based passenger car fleet. ... 97

(8)

vii

List of Figures

Figure 1. The main steps of the method used are shown in the figure. The writing of report was

done continuously throughout the project. ... 3

Figure 2. Principal design of an ERS. (Source: [10]) ... 11

Figure 3. The picture illustrates a truck driving on an electrified road using overhead lines. (Source: Scania [22]) ... 12

Figure 4. Example of an intelligent pantograph developed by Siemens. (Source: [23]) ... 13

Figure 5. Siemens eHighway system test track in Groß Dölln, Germany. (Source: [24]) ... 13

Figure 6. The picture shows how the electrical power is fed from the grid to the vehicle. (Source: [30]) ... 15

Figure 7. Cross section of the road with a rail in each half and cables buried outside the roadway. (Source: [30]) ... 15

Figure 8. The figure illustrates the principle behind the inductive power transfer from road technology. (Source [37]) ... 16

Figure 9. This figure illustrates the basis of the primove Highway architecture. (Source [8]). .... 17

Figure 10. The major stakeholders in the ERS. (Source [8]) ... 18

Figure 11. A Thomas Parker’s electric car from the 1880s. (Source: [39]) ... 20

Figure 12. Worldwide number of electric vehicles in use from 2012 to 2015. (Source: [41]) ... 21

Figure 13. Estimated Costs of EV Batteries through 2020. (Source: [54]) ... 23

Figure 14. The charging profile of a Tesla Supercharger. (Source: [60]) ... 24

Figure 15. The major road network in orange in United States. ... 25

Figure 16. The major road network in orange in parts of Europe. ... 26

Figure 17. The major road network in orange in Scandinavia. ... 26

Figure 18. The world transportation consumption by fuel. (Source: [64]) ... 27

Figure 19. The cost development of gasoline in Sweden excluding VAT from the year 1981 – 2015. (Source: [69]) ... 28

Figure 20. The cost development of diesel excluding VAT in Sweden between the years 2001 to 2015. (Source: [69]) ... 29

Figure 21. World total final energy usage by source for 2013. (Source: [73]) ... 29

Figure 22. World electricity generation from all energy sources in 2014. (Source: [78]) ... 30

Figure 23. Electricity prices in U.S. dollar cents per kilowatt hour excluding taxes. (Source: [79]) ... 31

Figure 24. Power production by source in the Nordic region in 2013. (Source: [82]) ... 32

Figure 25. An illustrative flow chart over the two models with accompanying submodels produced to investigate the thesis objectives. ... 33

Figure 26. Example of how a sectioning of Germany into quadratic road sections with ERS installation can be conceptualized (Note that the meshed road sections would in reality only be on the land area). ... 35

Figure 27. Viewing one square in the quadratic grid-mesh. ... 36

Figure 28. Explanation of why the circumferential length of a square in a large grid-mesh was approximated as 2x. ... 36

Figure 29. Cost development as a function of length x for battery, ERS installation and the combination of these two factors. ... 39

Figure 30. Vehicle kilometer as a function of road length. ... 50

Figure 31. Traffic intensity as a function of road length. ... 50

(9)

viii

Figure 32. Number of countries where the yearly profit is positive for different ERS technologies and battery cost scenarios. ... 56 Figure 33. Percentage of total number of vehicles worldwide in countries where the yearly saving is positive for different ERS technologies and battery cost scenarios. ... 56 Figure 34. Percentage of total number of heavy vehicles worldwide in countries where the yearly saving is positive for different ERS technologies and battery cost scenarios. ... 57 Figure 35. Percent of global total GHG emissions reduced by implementing the different ERS technologies in countries where the yearly savings are positive for different and battery cost scenarios. ... 57 Figure 36. The percentage of the countries in the world/continents that are suitable for conductive power transfer from road solution assuming the current battery pricing of 350 USD/kWh. ... 58 Figure 37. The percentage of the countries in the world/continents that are suitable for conductive power transfer from road solution assuming the predicted future battery pricing of 120 USD/kWh.

... 58 Figure 38. A summarization of all the cost differences presented in the previous tables ... 60 Figure 39. A summarization of the yearly savings or losses for each ERS technology and battery cost scenario. ... 62 Figure 40. The number of cars required until an ERS based system is cheaper for the two examined ERS technologies assuming 2015 battery pricing. ... 63 Figure 41. The number of cars required until an ERS based system is cheaper for the two examined ERS technologies assuming future battery pricing. ... 64 Figure 42. The frequency breakeven points for inductive and conductive ERS technologies. ... 65 Figure 43. The frequency breakeven point for overhead conductive ERS technology. ... 65 Figure 44. Accumulated result for the three different scenarios for conductive road ERS technology. ... 66 Figure 45. Accumulated result for the three different scenarios for overhead conductive ERS technology. ... 67 Figure 46. Accumulated result for the three different scenarios for inductive road ERS technology.

... 67 Figure 47. Accumulated result obtained from Scenario 1 for all ERS technologies. ... 68 Figure 48. The yearly development of GHG emission reduction for the three different scenarios for conductive and inductive ERS technology. ... 69

(10)

ix

Nomenclature and Abbreviations

Notations

Symbol Description

∆ Quadratic grid-mesh size in kilometer

x Length of a side in kilometer of a square in the quadratic grid-mesh k1 The cost of battery per kilometer and car

k2 Cost per car per km² grid

B(x) Function of battery cost by distance (km)

ERS(x) Function of ERS installation cost by distance (km)

f(x) Combined function of battery and ERS installation cost by distance (km)

Abbreviations

WTW Well-to-wheel

GHG Greenhouse gas emissions

CO2 Carbon Dioxide

EU European Union

MK1 Miljöklass 1

EV Electric Vehicle

DC Direct current

ERS Electric Road System

ICE Internal Combustion Engine

(11)

1

1 INTRODUCTION

This thesis is the final assignment for the master Sustainable Energy Engineering given under the program Energy and Environment at KTH Royal Institute of Technology in cooperation with Elways.

The thesis examines the prospect of Electric Road Systems, abbreviated as ERS, to be a solution to our dependency on fossil fuels and thus the future of transportation. ERS are technologies that enable continuous electricity transfer to vehicles in motion. In this report, the potential of different ERS technologies are examined from a technical, economic and environmental standpoint from a global and a Swedish perspective.

1.1 Background and Problem Description

The global energy usage has seen a constant increase since the industrial revolution and the trend is likely to continue for a foreseeable future. According to the U.S. Energy Information Administration, the world energy consumption is estimated to increase by 56 % until 2040 [1].

Transportation is a vital part of today’s energy-intensive society, and accounts for 20 % [2] of our global total energy usage. Furthermore, as almost 95 % of this energy originates from petroleum- based fuels, this results in a huge emission of greenhouse gases (GHG). In fact, in 2014, the transport sector alone accounted for approximately 14% of the total GHG emissions [3]. This development has compelled governments around the world to start setting goals to mitigate the increasing global pollution. For example, the Swedish Government has published a statement proposing a goal to make the Swedish transportation sector entirely fossil fuel neutral by the year 2030 [4]. Similarly, the European Union aims to have at least 10 % of the energy used in the transportation sector come from renewable energy sources by 2020 [5].

Although some difference of opinion and disputes remain regarding how dangerous greenhouse gases actually are for the environment, most experts agree that the peak-oil scenario is approaching and will eventually make fossil fuels too expensive to extract and use. As a result, it is of utmost importance that we as smoothly and quickly as possible transition to more sustainable fuels.

Vehicles powered by electricity using batteries, also known as electric vehicles (EV), are an alternative to traditional petroleum-powered vehicles. EVs have experienced tremendous progress during the last decennium due to a number of reasons, with the foremost reasons being the recent rapid development in the battery technology and the situation in the world where we are trying to progressively move away from fossil fuels. Even though electric vehicles might be a good potential alternative to petroleum-based vehicles, there still are a number of challenges that need to be addressed before EVs can become competitive enough to achieve the required breakthrough.

One of the major limitations for electrical vehicles are the capabilities for the current battery technology. Despite the fact that considerable development has been made in recent times within the field, the energy density of batteries is still substantially lower than the energy density of petroleum-based fuels [6]. Likewise, the charging time required is a major challenge in making electric vehicles more commercially attractive. Even with the latest fast charging technology, it

(12)

2

still takes up to 40 minutes to charge a battery with less range than what a full tank of diesel can provide [7]. Moreover, if we also want to electrify heavy vehicles (e.g. trucks and buses), it will not, in the foreseeable future, be possible to run these solely on batteries since the energy storage capacity and the output power of batteries is not enough for long-distance transportation of heavy vehicles [8]. Hence, the main obstacle towards electrifying heavy vehicles is the size and weight required for on-board storage of electrical energy. As an example, a road truck weighing 40 tons travelling 1,000 kilometers would require batteries weighing approximately 20 tons. The batteries would in this case take up far too much of the cargo space and would thus make the heavy vehicles highly unprofitable. To make the EV less reliant on the battery, especially for long distance heavy transport, and at the same time reduce the vehicle cost, a possible solution could be to transfer power to the vehicle from the road.

ERS are systems that enable dynamic power transfer to the vehicles from the roads they are driving on. In an ERS based road transportation system, the largest roads would be electrified so that the bulk distance travelled by vehicles would be done using external electric power. The remaining distance outside the ERS network could be performed by for example either using an internal combustion engine (ICE) or by using (small) on-board batteries optimized for shorter routes. By utilizing ERS, both the cost and weight of the batteries could be kept to a minimum and the requirement for stops for recharging would also be eliminated since it would be possible to recharge while driving [8]. There are a number of ways and technologies available that can be utilized in transferring power from the roads to the vehicle. However, there are currently in principal three ERS technologies that have shown potential and are considered in the industry.

These are more specifically the conductive power transfer through overhead lines, conductive power transfer from rails in the road and inductive power transfer through the road [9].

As the ERS industry is relatively new, not many research reports have as of yet been published in this field. Furthermore, the reports that have been published are usually limited to examining only one ERS technology and look at the potential of this technology on a specific road case. For example, Viktoria Swedish ICT has in collaboration with different stakeholders compiled a detailed evaluation of both the inductive road technology and the overhead conductive road technology ( [10], [8]). However, both these reports assess the potential of the technologies from only a heavy vehicle transportation perspective and include cost estimates for a full deployment of a road section between Stockholm and Gothenburg. Similarly, the report published by Andersson and Edfeldt [11] compares the potential of ERS heavy-duty trucks with conventional and hybrid heavy-duty trucks from a haulage contractor companies’ perspective by examining different road cases [11]. A couple of reports that aim to summarize the ERS concept and evaluate its potential have been published ( [12], [13], [14]). Moreover, reports that examine different business models and payment methods for ERS have also been produced ( [15], [16]).

Consequently, it was found that not much research existed which looked at a full-scale implementation of the different ERS technologies from a global but also a Swedish perspective and which compared the ERS technologies between each other. This thesis aims to therefore evaluate and compare the potential of a full-scale implementation of different ERS technologies in different countries of the world from predominantly, an economic and environmental perspective.

(13)

3

1.2 Purpose

The purpose of this study is to investigate whether it is possible to replace the majority of the transport sector's dependency on petroleum-based fuels by introducing ERS. More specifically, the purpose is to:

1) Investigate the possibility of a full-scale implementation, predominantly from an economic standpoint, for different ERS technologies around the world. Subsequently, to identify the top countries/regions with the best and the worst prospects.

2) Examine the potential for implementation of ERS in Sweden and compare the different technologies available from a primarily economic and environmental perspective.

Furthermore, this thesis explores using different scenarios, how an expansion might look like until the year 2050.

1.3 Method

The thesis method is essentially split into four distinct parts, namely, literature review, modelling, analysis of findings, and report writing. This is illustrated using different subparts in Figure 1 where the writing process was continuous throughout all the parts. The process was performed iteratively in order to facilitate improvements continuously.

As in most projects, the first step was to study relevant articles and reports in order to understand and create a broad picture about ERS and the surrounding topics. Early on, the scope and appropriate limitations were discussed and decided on together with supervisors at KTH and

Litterature Review

- Reports - Articles - Interviews

- Internet

Modelling

- Excel - Economic and environmental model

- Scenario analysis - Sensitivity analysis

Analysis

- Evaluation and improvement of

findings

Figure 1. The main steps of the method used are shown in the figure. The writing of report was done continuously throughout the project.

(14)

4

Elways. Reports and articles were then collected from various different sources which included administrative authorities, ERS companies, and stakeholders within the ERS field just to name a few. Collecting information from different stakeholders in the field was done in order to capture different views and aspects of ERS technology. A number of interviews, both in person or through a communication medium i.e. telephone, were performed with relevant stakeholders. Open questions were mainly used to ensure that the responses were formulated by the interviewee him- /herself which promoted unbiasedness. Naturally, the questions were varied depending on the field of expertise of the person being interviewed. Both qualitative and quantitative data was acquired from these interviews. However, literature in the form academic reports, articles, web pages of companies, administrative authorities, etc., were mainly used as sources of information for the data used in the modelling process.

To be able to answer the proposed inquiries, the thesis was split into evaluating the ERS field using two different conceptual models. These models aimed to analyze and compare the prospect of different ERS technologies from a technical, economic and environmental standpoint for a global and a Swedish perspective. The methodological approach applied for each model was different.

Therefore, the modelling procedures used for the two models are presented in more details in Chapter 3. All modelling was performed in the spreadsheet program Microsoft Excel. This program was chosen because of a number of reasons, firstly, it was found to give a great overview over the modelling process. It also made following equations step by step simpler. Moreover, adding/changing inputs and altering equations could also be accomplished smoothly. For each model, specific input data was collected which was mostly compiled from literature and through making various assumptions (See chapter 1.5 for further details).

During the course of the thesis, work was carried out in a close contact with both the supervisor at KTH and the supervisor at Elways. Both have contributed with feedback, information and quality checks. This close collaboration was upheld through frequent meetings held approximately every second week.

1.4 Delimitations

Some overall limitations of the thesis are presented in this section. Additionally, other limitations are presented continuously in the report when judged necessary. The major limitations are:

 The economic calculations made in this thesis only consider the techno-economic direct costs and are thus only a partial cost of the actual complete economic expenditures. For example, the cost for society in terms of lost jobs in the fossil fuel related markets are not considered.

 The operational costs are only considered in the expansion model (submodel 4) and are hence neglected in the remaining models.

 Only 184 countries could be studied in the global perspective model due to insufficient data being available for the remaining countries.

 The different alternatives of payment systems for ERS have not been investigated in this thesis.

(15)

5

 The probability that the electricity cost will most likely increase in the future due to wider implementation of renewable energy sources and possible imposition of new taxes is not considered.

 No speculation over the future price trend was made for gasoline and diesel, hence, contemporary prices were used for future scenarios as well.

 In the calculations, the cost of expanding the electric grid to enable connections to the electrified roads has been neglected. Furthermore, the power grid and the electricity distribution technologies required for ERS are not considered.

 The installation price of the different ERS technologies is kept the same as the current anticipated prices when modelling the future.

 Electricity is the only energy source for vehicles that has been compared as an alternative to fossil fuels. Hence, other potential alternative fuels such as biofuels, hydrogen fuel cells, etc. are not considered.

 Battery storage is the only hybridization alternative considered for electric vehicles in combination with ERS.

 The current models do not take into consideration that when vehicles are travelling on the electrified roads, the efficiency becomes higher than when utilizing the battery as energy source. This is due to the fact that the electric motor in the EVs receive the energy directly from the ERS, thus the efficiency loss obtained from battery storage is bypassed. This would in reality result in a lower energy consumption per kilometer for the vehicles while travelling on electrified roads.

 Any form of energy regenerative systems in the vehicles and/or in the ERS have been ignored.

1.5 Assumptions

In this report certain assumptions and simplifications were made to enable various calculations and models, which otherwise would have made the problem excessively complex. Since the correct assumptions are a vital part of a well-conducted scientific report, each assumption was heavily scrutinized and studied before it was adopted. The overall major assumptions made for this thesis are presented in this section. Moreover, for each model, more specific key assumptions are presented in subsections. Finally, in Appendix C, some additional assumptions that were judged to be too detailed for the main report body are presented.

 In these models, motor vehicles were split into four main vehicle types. Namely, passenger cars, light-duty trucks, heavy-duty trucks and buses.

 It was assumed that all the current motor vehicles only use either diesel or gasoline as fuel, thus vehicles that already use alternative fuels are disregarded in the models.

 It was assumed that each country will phase out all the fossil fuel based vehicles by replacing them with only electric vehicles that use batteries as energy source.

(16)

6

 Three different ERS technologies were examined in this thesis, namely Elways conductive road technology, Siemens overhead conductive technology and lastly, the inductive road technology of Bombardier.

 It was assumed that the conductive road and inductive ERS could be used by all vehicle categories. However, the overhead conductive ERS was presumed to only be used by heavy-duty trucks and buses, denoted together as heavy vehicles.

 It was assumed that the road network in all countries can be approximated as quadratic grid-meshes. This assumption is not that far from reality where many countries have a well- connected road system in a meshed manner as shown in the frame of reference chapter about the road network in the world.

 The cost of installing inductive road, overhead conductive and conductive from road technologies was assumed to be 15 MSEK/kilometer, 6 MSEK/kilometer and 4 MSEK/kilometer respectively. The lowest predicted cost for each technology was used, as a construction at such a huge scale would probably lead to the lowest prices due to economies of scale. In the case of inductive road technology, the cost per kilometer was assumed to be lower than what was found through the literature study. This was chosen by the author to fathom the potential of the technology in a best case scenario.

 Cost of the pickup arm for conductive road power transfer has been estimated to be roughly 4500 SEK. According to Gunnar Asplund, this is a reasonable assumption as the prices would decrease considerably if the pickup arm was mass produced due to economies of scales. The cost of the pantograph for overhead conductive is assumed to be 55 000 SEK and the inductive pickup system is assumed to have the same cost as the conductive road technology. Naturally, this will result in an underestimation of the real cost as the pickup arm for conductive road power transfer is expected to be cheapest out of the two options.

However, this method will still show the situation under a best case scenario for the inductive road technology.

 The average fuel consumption for all the categories of vehicles, taking into account both diesel and petrol driven vehicles, was computed to be 0.1 l/km. On the other hand, the average fuel consumption for heavy-duty trucks and buses was calculated as 0.38 l/km.

 Due to the fact that the cost of diesel and gasoline have seen a sharp decrease in pricing during the last year. It was judged necessary to use an average of the price over some years.

The price used in this model was the average gasoline and diesel price excluding VAT for the last five years in Sweden, taking into account the vehicle categories, and was computed to be 5.8 SEK/l. Even though the Swedish gasoline and diesel price is a bit on the expensive side when considering a global perspective. It was concluded that the assumption still gave adequately accurate output for a global perspective. The diesel price used for the heavy transports was set as 5.6 SEK/l.

 Additionally, the combined average emission from diesel and gasoline for all the vehicle categories was computed to be 2747 g CO2e/l. Whereas, the emission from diesel was set to be 2820 g CO2e/l.

 For an average electric car, the energy usage used in this report was 0.16 kWh/km. This was estimated by comparing multiple factual sources. The average electricity usage

(17)

7

considering all the vehicle categories was estimated to be 0.24 kWh/km. Additionally, the average electricity usage for heavy vehicles was calculated to be 1.06 kWh/km.

 The technical lifespan of ERS, batteries and pickup apparatuses are assumed to be 20, 8 and 15 years respectively.

 To simplify calculations, the exchange rate for 1 USD was set to a constant value of 8 SEK.

Similarly, 1 EUR was assumed to be have an exchange rate of 9 SEK.

 Cost of battery in 2015 is assumed to be 350 USD/kWh and battery prices in the future (after 2020) as 120 USD/kWh.

 The real interest rate has been assumed to be 4 % when using the fixed-rate mortgage method as used by Sweco and the Swedish Transport Administration [17].

1.5.1 Model 1 – World

This model was developed with the aim to get a general idea about which countries and regions in the world that are the most attractive for ERS solutions. The main questions that the model targeted to answer were: If a full-scale implementation of ERS was performed globally in combination with electric vehicles, which countries would currently be the most appealing from primarily an economic standpoint. Also, comparing the cost of implementing a full-scale ERS for passenger cars against the cost of converting all passenger cars to pure battery electric cars, which alternative would be the most economically beneficial? To be able to answer these questions a number of additional assumptions were found necessary to be made and the most important of these are presented below. Specific assumptions for each submodel are reported under subheadings.

 It was assumed that the ERS solutions are already completely implemented in the countries and thus, the building phase was not considered. Instead a steady-state case was estimated where the yearly costs and savings were analyzed.

 As the exact distribution for the different motor vehicle types could not be acquired for each country, the division of the four categories of vehicles for Sweden and their percentile of vehicle kilometer was assumed to be the same for all the countries in the world.

Consequently, this resulted in the fact that the average distance travelled, fuel consumption, electricity consumption, fuel price and emission was assumed to be the same as for Sweden presented in Model 2. This assumption has been made to facilitate the computations as not enough reliable data could be acquired regarding the exact distribution of the different categories of vehicles in each country.

 Only the land area of the studied countries was used where land area is defined as the sum of all surfaces delimited by international boundaries and/or coastlines, excluding inland water bodies (lakes, reservoirs, rivers).

 To ensure that the EVs would have sufficiently big batteries and thus would not run out of charge, it was assumed that the batteries should be able to drive at least the length of a side of a quadratic grid-mesh, which are the electrified roads.

 0.7 SEK/kWh, which is the rough median of the global electricity price, was used as the average global electricity cost as it was judged to be more accurate than the mean.

Additionally, the average global electricity emission used in the model was 500 g CO2e/kWh.

(18)

8

Comparison – Petroleum-Based Road Transport against ERS and EV Combination

 The cost of a conventional petroleum-based vehicle is estimated to be the same as for an electric vehicle without the battery and the pick arm apparatus that connects to the electrified roads. This has been computed by comparing the current vehicle prices.

 As a result, the yearly cost of an ERS based transport sector is assumed to be the annual cost based on life expectancy of the electrified roads, the new batteries, the new pick up arms and the electricity consumption from all the electric vehicles.

 The total yearly cost of the current petroleum-based transport system was assumed to be the cost of fuel used by the vehicles.

Comparison – Pure Battery Electric Car Fleet against ERS and Electric Car Combination

 In this model, only the passenger cars were examined. Thus, only the conductive road and inductive road electric road technologies are considered.

 It was assumed that the cost of electric passenger cars without the battery is always the same, regardless of the size of the battery.

 The yearly cost of a pure battery electric car based fleet was assumed to be the yearly battery plus the infrastructure costs.

 The cost of the two ERS technologies was assumed to be 1/5 of the normal price, due to the fact that the ERS would be dimensioned for only passenger cars and thus would require lower loads. This estimation was made by Elways [18].

 The acceptable driving range that an electric car needs to travel to be a viable competitor against conventional vehicle was assumed to be a bit lower than the average driving distance for conventional vehicle, which is roughly 600 kilometers. Therefore, for this model, the minimum acceptable driving range for an electric passenger car was assumed to be 500 kilometers.

 It was assumed that the only infrastructure investment for a pure battery electric car fleet would be fast chargers.

 When it comes to the cost for a fast charger, it was found that the average cost of building a Tesla supercharging station with five Superchargers is 137 500 USD which translates to that each supercharger/fast charger would cost roughly 220 000 SEK.

1.5.2 Model 2 – Sweden

The goal of this model was to further investigate how the prospect for the different ERS technologies is in Sweden. This was done by developing four different submodels that examined the problem from different perspectives. The first two models were the same as in Model 1, with chief difference that the input data was optimized for Sweden. The third submodel aimed to investigate the frequency of electric vehicles per day needed on an electrified road section that would result in a repayment of the investment. Finally, the last model intended to explore how an expansion and implementation of ERS could look like in the future. For each model, some assumptions were found necessary to be made and the most important ones are presented in this

(19)

9

chapter. Furthermore, the chief specific assumptions for the last two submodels are reported under the coming subheadings.

 The values from 2015 were used for population, land area, total GHG emissions, yearly GDP and electricity consumption.

 The cost of Nordic electricity mix for the year of 2013 has been assumed, which was 0.355 SEK/kWh.

 The input for number of vehicles, including all the vehicle categories, in Sweden year 2015 was found to be roughly 5.9 million. The number of heavy vehicles in Sweden year 2015 was estimated to be about 114 500.

Submodel 3 – Finding the Breakeven Point

 The daily investment cost per kilometer for conductive road, overhead conductive and inductive road electric road technologies were found to be 818 SEK/day, 1226 SEK/day and 3066 SEK/day respectively and was computed by using the fixed-rate mortgage method.

Submodel 4 – Expansion

 The value for the total kilometer of electrified road needed for a full-implementation for the three different ERS technologies was assumed to be the values computed using Model 1 for future battery price.

 For this model it was assumed that the most heavily trafficked road sections would be the first to be electrified as they would lead to the largest cost savings.

 The model considered the time period from 2016 to 2050. It was assumed that a full implementation of ERS and a full electric-based transport sector would be attained until, at the latest, 2050.

 The total yearly vehicle kilometer, new vehicles per year and the total number of vehicles are assumed to always be constant and have the same values as in 2015. These assumptions were found to be essential in producing the functions relating vehicle kilometer and vehicle frequency with road length.

 The electricity and fuel prices were presumed to be constant, thus no prediction of the future cost development was made.

 The average fuel consumption, average electricity consumption, average fuel and electricity emissions were assumed to be constant.

 The cost for road maintenance was assumed to be 60 SEK/km/day for all ERS technologies.

This cost was obtained from Elways [18], and is derived from the road maintenance cost of regular roads.

 The cost of electrifying the roads for each technology was assumed to be 2.5 times more expensive than the normal cost for the first 100 km and 1.5 times more expensive for the first 1000 meters. This was done to mimic that the initial installments would be more expensive compared to later ones due to economy of scales.

(20)

10

2 FRAME OF REFERENCE

This chapter gives a broad picture of the current knowledge in the field of ERS and other relevant areas. The information presented in this chapter is the base for the modelling and is used as input parameters for the different models.

2.1 Electric Road Systems

Electric Road Systems (ERS) are in principle electrified roads that are able to perform dynamic power transfer to the vehicles on the road. Normally an electric engine receives power from an external power source which has been integrated into the surface of the road. The transmission of the electrical power is made while the vehicles are in motion in a similar fashion as that for trolley buses, where the main difference is that ERS-vehicles can connect and disconnect from the power supply while in motion. Consequently, the roads with installed ERS can be used by both conventional fossil fuel based vehicles as well as ERS-vehicles. To make ERS-vehicles more flexible they are often equipped with batteries or smaller internal combustion engines (ICE) so that they also can be used on conventional roads [10].

The key actors in the industry believe that the ERS technology is technologically feasible and could be a potential solution in reducing society’s fossil fuel dependency and thus also the emissions in the transportation sector [10]. Though there are disagreements among experts over how long a full transition to ERS will take to be realized (anything between 10 to 50 years has been proposed), there is a consensus that this switch is possible to make. Naturally, the change is expected to take place progressively, starting with smaller demonstration projects and closed road systems to gradually incorporating major national and international highways. Several demonstration projects have already been initiated around the world to explore and evaluate the different ERS technologies and their full-scale commercial prospective [10]. Even though a deployment of ERS for road transportation will require huge investments in the infrastructure, a full-scale implementation could lead to significant advantages compared to the currently existing fossil fuel dependent transportation system.

One of these advantages obtained would be reduced operation costs due to ERS being more energy efficient and electricity being cheaper than fossil fuels. Additionally, the electric engines would reduce the noise generated, which would allow the heavier vehicles to run during off-traffic hours.

Consequently, this would result in decreased congestion and a balancing of the energy demand.

There is also a potential that as electric engines are simpler and lighter than traditional internal combustion engines, the vehicle maintenance costs would experience a reduction [8].

(21)

11

Figure 2. Principal design of an ERS. (Source: [10])

There are essentially three physical ways that a vehicle can be charged while being on the road, namely from above, the side or from below. Unfortunately, charging from the side is considered to be too dangerous for pedestrians and bicyclists due to the fact that an arm apparatus would need to stick out from the side of the vehicle, this approach is not considered as an alternative [19]. As a result, there are currently in principal three technologies of ERS that are considered in the industry, namely, conductive power transfer through overhead lines, conductive power transfer from rails in the road and inductive power transfer through the road [9]. In the coming chapters these technologies are presented in more detail.

2.1.1 Overhead Conductive Transmission Technology

The overhead contact line technology has existed for many years and is conductive based; in fact it is the same technology that is used in today’s trains, trams and trolleybuses. Simplified, in such a system, electricity is continuously transferred from the overhead lines to the vehicle through a so called pantograph. A pantograph is a component that connects the overhead lines to the vehicle and can in such way transfer electricity between the overhead line and the vehicle. Along the roads there are electricity pylons that support the electricity wires. The systems using overhead contact lines today are commonly closed systems. They usually involve vehicles that travel along a pre- set path while continuously been connected to the overhead lines and in most cases also are connected to a rail in the ground [20].

However, when it comes to overhead contact lines for ERS-vehicle applications, it is of utmost importance that the vehicle should be able to connect to and disconnect from the overhead lines while moving. Once an ERS-vehicle is disconnected it would automatically switch to a secondary source for propulsion energy such as a hybrid-diesel engine or batteries [21]. At present, the technology with overhead contact lines is only supported for large vehicles such as trucks and hence cannot be used by passenger cars and other low vehicles [13]. This is mainly due to the fact that height regulations state that the electrified overhead lines on roads need to be above a certain height from the ground. For example, the Swedish National Electrical Safety Board claim that high voltage wires need to be located at least 6 meter and low-voltage 5.1 meter above the ground due to safety reasons. Therefore, using the overhead technology for passenger cars would require the cars to be equipped with a pickup arm of several meters which would not only be technologically challenging but a huge safety hazard [20].

(22)

12

Figure 3. The picture illustrates a truck driving on an electrified road using overhead lines. (Source: Scania [22])

Traditionally, when the overhead transmission technology is used for trams and trains, the rail is used to handle the return circuit. But as the ERS lack rails, a two-pole system is needed to be implemented so that both the power in-feed as well the out-feed can be managed. With this system it would also be possible to feed the regenerative braking power from the trucks back to the overhead line and into the energy grid so that it can be used by other vehicles in the system. The specially designed overhead contact lines are made in a way that ensures that secure energy supply can be performed for speeds up to 90 km/h [21].

Active Pantograph

The overhead transmission line technology that will be used for the ERS will need to be dynamic and intelligent, as the vehicles travelling on the electrified roads will need to be able to perform a number of complex procedures. This involves for example overtaking other vehicles, passing under bridges and driving over non-electrified parts of the road network, exiting highway etc. Not to mention the fact that as the vehicles on an electrified road system would not be travelling on a fixed rail, there would be some lateral displacement of the vehicle on the road as it would be impossible to travel in a perfectly straight line. Naturally, it is thus of paramount importance to design a pantograph that is flexible and can intelligently handle different kind of traffic situations without problems [20]. Such an intelligent pantograph is required to enable continuous electricity transmission between the overhead line and the vehicle even during high travelling velocities and when the vehicle is somewhat laterally displaced compared to the transmission line. It also has to be able to handle vertical changes in the form of bumps or the road being raised due to frozen ground. Another important aspect of such a pantograph is the need of an automatic search system that can find the overhead lines when they are available. Several scanning technologies are available or are being developed to meet this need. It has been suggested that as a traditional pantograph cost somewhere between 30 000 – 80 000 SEK it is not unlikely to propose that more intelligent pantograph will have a price range between 120 000 – 240 000 SEK [20].

Even though several companies in the industry have developed overhead conductive technologies, in this thesis, only the Siemens eHighway overhead conductive concept is studied in detail.

(23)

13

Figure 4. Example of an intelligent pantograph developed by Siemens. (Source: [23])

Siemens – eHighway

Siemens has developed the eHighway system that uses the overhead transmission line technology.

It enables hybrid trucks to travel using electricity from overhead contact lines via an active pantograph, which makes it possible for the trucks to disconnect and connect at speeds up to 90 km/h. Due to the fact that direct transmission is used, it permits the system to have an 80-85 % well-to-wheel (WTW) efficiency, which is twice as high as that for conventional diesel engine.

The eHighway system also makes it possible to regenerate the breaking energy which further increases the system WTW efficiency, lowers the emissions and the energy costs [23].

The active pantograph developed for the eHighway system is considered to be one of the key innovations. Apart from enabling the vehicles to connect and disconnect from the overhead lines, it furthermore has a specially designed sensor technology that permits the pantograph to automatically adjust its position to compensate for any lateral movement of the truck compared to the contact lines. This contrivance also minimizes the wear induced by the pantograph and thus possibly enables a longer lifecycle [23].

Figure 5. Siemens eHighway system test track in Groß Dölln, Germany. (Source: [24])

(24)

14

For the sections on the roads that are not electrified with overhead contact lines, the eHighway adapted trucks are able to switch to a hybrid drive. There are no restrictions with regards to the type of hybrid drive that can be used by the trucks. Serial and parallel concepts with internal combustion engines, battery solutions, fuel cells etc. are all possible to implement [25].

Since the technology is not yet in commercial use, it is difficult to estimate the investment costs for the technology. However, the consulting firm, Grontmij, stated in their report from 2012 for the Swedish Transport Administration and the Swedish Energy Agency that the cost of building such a system would be around 10 million SEK per kilometer. The Swedish Transport Administration made its own estimation in 2012 that the cost would be somewhere around 6-18 million SEK per kilometer, where electrification at a larger scale would result in costs in the lower end of the span [26].

2.1.2 Conductive Power Transfer from Road

The conductive power transfer from the road is a newer technology compared to that of overhead contact lines. It was the French company Alstom with their conductive road transfer technology, Aesthetic Power Supply (APS), who opened the first tramway system in Bordeaux (2003) which used conductive road transfer technology. Not only did the APS technology prove that conductive road transfer is possible, but also exhibited that the technology was safe to use and more aesthetically pleasing according to some then compared to traditional overhead contact lines. Since then several cities around the world have incorporated the APS system [27]. In 2015 Alstom launched SRS, which is an innovative ground-based static charging system for both trams and electrical buses based on the proven APS technology. Alstom has furthermore been working in collaboration with Volvo on an ERS that allows continuous conductive power transfer from road for trucks [28]. The Swedish company Elways has also developed its own technology of conductive power transfer from road known as Elways. Unlike the ERS developed by Alstom and Volvo which is designed only for trucks, Elways has instead developed a system that can be utilized by all types of vehicles [18] . In this thesis, only the conductive road transfer technology developed by Elways is examined due to time and data restrictions and as such other companies’

conductive road transfer solution are not considered.

Elways

In summary, Elways technology enables electricity transmission from the power grid to rails in the road. This means that there is a need for a current collector or pickup arm to connect the rails in the road to the vehicles. To increase the overall safety for humans and animals, the power supply rails is segmented, similarly to the APS system. For Elways technology, a distance of 50 meters is electrified at a time. This segment is fed with electricity from a low voltage AC cable with a voltage of 800 V which is positioned in the close vicinity of the road. The electricity input to the rails in the road is in turn made via a fast switch box located in the ground. This low voltage cable is then connected to a medium voltage cable (24 or 36 kV) which is placed next to the low voltage cable or further away from the road area. The transmission between the medium voltage cable and the low voltage cable occurs through a transformer station which is positioned every one or two kilometers. Lastly, the medium voltage cable is connected to the high voltage grid via a transformer station located every 50 kilometer or so [29].

(25)

15

Figure 6. The picture shows how the electrical power is fed from the grid to the vehicle. (Source: [30])

To minimize the risk of accidents due to the high voltages in the rails, Elways have positioned the conductors in trenches below the surface of the road. Hence, making it near impossible for humans or animals to reach the electrified part while walking over the rails. Furthermore, as the rails are only energized in segments of 50 meters at a time, the risk of getting electrocuted is reduced even further. The system also only supplies electricity to vehicles that are travelling over a certain velocity; this means that when a vehicle stops the current is likewise turned off. Another factor that can be a problem for ground based conductive rail systems is the weather. Elways have tested and proven that small objects such as stones, snow and rain can all be rinsed off the tracks automatically, using patented solutions, when the traffic intensity is sufficiently high [31]. Several tests have been performed in all weathers at Arlanda (outside Stockholm) test tracks which show that the system works satisfactorily [32]. A special add-on plough for a plough car has been proposed which can take care of the ice and snow in the rails during extreme winter conditions.

Moreover, a heating system in the rails can also be implemented to eliminate this problem [31].

Figure 7. Cross section of the road with a rail in each half and cables buried outside the roadway. (Source: [30])

As with the overhead contact line technology, a key technology in conductive road transmission is the electricity pickup that is to be used by the vehicles. The pickup arm developed by Elways has a flexible mechanical construction that enables it to follow the rail even when the vehicle is not perfectly aligned to the rails. In addition, the pickup arm has a sensor that allows it to automatically connect or disconnect from the rail when a rail is available or while the vehicle is overtaking [33]. Transmission of power from the track to the car through the pickup has been performed for speeds up to 50 km/h. The pickup arm is estimated to cost around 5000-10 000 SEK and will be constructed to have a lifespan similar to that of vehicles. The system has been proven

(26)

16

to be able to conduct voltage and current that together correspond to 200 kW per track, which is the power necessary to charge trucks [34]. The lifespan of the contacts in the rails are estimated to have a technical lifespan of approximately 20 years depending on the traffic intensity [18]. Higher intensity would naturally lead to more frequent replacement of the rail.

Elways has stated that the cost of a large-scale expansion, more than 1000 kilometers, will cost around 4-5 million SEK per kilometers. It has also been estimated that the construction of the first 100 kilometers will cost 7 to 10 million SEK per kilometers. Additionally, the cost of road maintenance in the form of cleaning of the rails from dirt, water and snow has been predicted to be about 60 SEK per day and kilometers [29]. Gunnar Asplund has stated that the well-to-wheel efficiency of the Elways system will be somewhere between 85-95 % depending on the choice of the voltage and the quality of the electrical components [35].

2.1.3 Inductive Power Transfer from Road

Inductive ERS use induction principles to transfer electricity wirelessly to moving vehicles, which means that no mechanical contact is required [36]. Simplified, the inductive power transfer technology utilizes the AC transformer principle. Figure 8 can be used to describe this principle.

Typical AC transformers, which commonly are used in power distribution systems, have laminated iron core that lead the magnetic flux from a primary winding through a secondary winding with miniscule efficiency loss due to loss and leaking. This is displayed in picture A. However, to enable the inductive power transfer technology, the core is split into two separate parts as shown in picture B. Consequently, the inductive power transfer by road technology works by having the secondary winding of the transformer placed in the vehicle while the primary winding is elongated and installed into the road. This allows magnetic flux to be transferred between the road and the vehicle, thus enabling continuous power transfer as shown in picture C [8]. To allow the transmission, also this solution requires a type of pick-up arm, which corresponds to the second side of the transformer as exemplified in picture C.

Figure 8. The figure illustrates the principle behind the inductive power transfer from road technology. (Source [37])

Electric Road Systems

Electric Road Systems

A feasibility study investigating a possible future of road transportation

Archit Singh

Electric Road Systems

A feasibility study investigating a possible future of road transportation

Abstract

Elektriska vägsystem

Genomförbarhetsstudie kring en möjlig framtid för vägstransport

Sammanfattning

Acknowledgements

Table of Contents

List of Tables

List of Figures

Nomenclature and Abbreviations

Notations

Symbol Description

Abbreviations

1 INTRODUCTION

1.1 Background and Problem Description

1.2 Purpose

1.3 Method

Litterature Review

Modelling

Analysis

1.4 Delimitations

1.5 Assumptions

2 FRAME OF REFERENCE

2.1 Electric Road Systems