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Xylia, M., Leduc, S., Laurent, A.-B., Patrizio, P., van der Meer, Y., Kraxner, F. & Silveira, S. (2019). Impact of bus electrification on carbon emissions: The case of Stockholm. Journal of Cleaner Production, 209, 74-87
Open this publication in new window or tab >>Impact of bus electrification on carbon emissions: The case of Stockholm
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2019 (English)In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 209, p. 74-87Article in journal (Refereed) Published
Abstract [en]

This paper focuses on the potential impact of various options for decarbonization of public bus transport in Stockholm, with particular attention to electrification. An optimization model is used to locate electric bus chargers and to estimate the associated carbon emissions, using a life cycle perspective and various implementation scenarios. Emissions associated with fuels and batteries of electric powertrains are considered to be the two main factors affecting carbon emissions. The results show that, although higher battery capacities could help electrify more routes of the city's bus network, this does not necessarily lead to a reduction of the total emissions. The results show the lowest life cycle emissions occurring when electric buses use batteries with a capacity of 120 kWh. The fuel choices significantly influence the environmental impact of a bus network. For example, the use of electricity is a better choice than first generation biofuels from a carbon emission perspective. However, the use of second -generation biofuels, such as Hydrotreated Vegetable Oil (HVO), can directly compete with the Nordic electricity mix. Among all fuel options, certified renewable electricity has the lowest impact. The analysis also shows that electrification could be beneficial for reduction of local pollutants in the Stockholm inner city; however, the local emissions of public transport are much lower than emissions from private transport.

Place, publisher, year, edition, pages
ELSEVIER SCI LTD, 2019
National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:kth:diva-244097 (URN)10.1016/j.jclepro.2018.10.085 (DOI)000457351900008 ()2-s2.0-85056180054 (Scopus ID)
Funder
Swedish Energy Agency, 39254-1
Note

QC 20190219

Available from: 2019-02-19 Created: 2019-02-19 Last updated: 2019-02-19Bibliographically approved
Barragán-Beaud, C., Pizarro-Alonso, A., Xylia, M., Syri, S. & Silveira, S. (2018). Carbon tax or emissions trading?: An analysis of economic and political feasibility of policy mechanisms for greenhouse gas emissions reduction in the Mexican power sector. Energy Policy, 122, 287-299
Open this publication in new window or tab >>Carbon tax or emissions trading?: An analysis of economic and political feasibility of policy mechanisms for greenhouse gas emissions reduction in the Mexican power sector
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2018 (English)In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 122, p. 287-299Article in journal (Refereed) Published
Abstract [en]

This study provides a comparative assessment of carbon-pricing instruments for the Mexican electricity sector, contrasting a carbon tax with an emissions trading scheme (ETS). The assessment is performed in terms of economic impacts and political feasibility. Model-based scenarios considering different price and quantity levels are analyzed on Balmorel-MX, a cost optimization bottom-up model of the Mexican electricity system. The political feasibility is evaluated using an online survey and interviews with representatives of relevant stakeholder groups. The assessment suggests that an ETS is the most appropriate instrument for the Mexican case. We recommend to set the cap as 31% abatement in relation to a baseline, which is suggested to be 102 MtCO2 by 2030, given the business-as-usual baseline used as reference by the Mexican government (202 MtCO2) is found to leave cost-effective abatement potential untapped. An emission trading system with such design has higher cost-efficiency and lower distributional effects than a carbon tax at equivalent ambition level (15 USD/tCO2). The political feasibility analysis confirms the assessment, as it is in line with the priorities of the stakeholder groups, allows earmarking carbon revenue and avoids exempting natural gas from carbon pricing.

Place, publisher, year, edition, pages
Elsevier Ltd, 2018
Keywords
Carbon pricing, Climate policy, Electricity sector, Energy systems analysis, Mexico, Political feasibility, Carbon, Commerce, Cost effectiveness, Economic analysis, Electric industry, Emission control, Gas emissions, Greenhouse gases, Systems analysis, Me-xico, Costs, carbon emission, electricity industry, emissions trading, energy market, environmental policy, feasibility study, greenhouse gas, political economy, pollution tax, Mexico [North America]
National Category
Energy Systems
Identifiers
urn:nbn:se:kth:diva-236612 (URN)10.1016/j.enpol.2018.07.010 (DOI)000447576700027 ()2-s2.0-85050804343 (Scopus ID)
Note

Export Date: 22 October 2018; Article; CODEN: ENPYA; Correspondence Address: Pizarro-Alonso, A.; Energy Systems Analysis, Department of Management Engineering, Technical University of DenmarkDenmark; email: aroal@dtu.dk; Funding text: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Authors would like to thank the Partnership Program between Denmark and Mexico for Energy and Climate Change, the Danish Energy Agency and EA Energy Analyses for introducing the Balmorel model in Mexico. In addition, authors would also like to thank Hans Ravn for the comments regarding Balmorel, and Samuel Cross for his guidance in the initial phases of this research. The authors would like to thank the anonymous reviewers for the valuable feedback provided. Appendix A. QC 20181119

Available from: 2018-11-19 Created: 2018-11-19 Last updated: 2018-11-19Bibliographically approved
Xylia, M. & Silveira, S. (2018). The role of charging technologies in upscaling the use of electric buses in public transport: Experiences from demonstration projects. Transportation Research Part A: Policy and Practice, 118, 399-415
Open this publication in new window or tab >>The role of charging technologies in upscaling the use of electric buses in public transport: Experiences from demonstration projects
2018 (English)In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 118, p. 399-415Article in journal (Refereed) Published
Abstract [en]

Electrification of public bus transport services is currently being explored in various demonstration projects around the world. The objective of this paper is to (i) gather insights from electric bus demonstration projects with a focus on charging technologies (conductive, inductive) and strategies (slow, fast); and explore the role these factors may play as upscaling of electric bus deployment is considered. The focus is on the Nordic region. A survey with stakeholders involved with electric bus demonstration projects is performed for understanding the benefits and drawbacks of each solution, and identifying the main themes emerging from project implementation and upscaling. Advantages of the conductive charging include the maturity of the technology and its higher maximum charging power compared to currently available inductive alternatives. On the other hand, inductive technology entails other benefits, such as the lack of moving parts which could reduce the maintenance costs for infrastructure, as well as minimal visibility of the equipment. The main issues likely to impact the upscaling of electric bus use are related to the maturity, cost-effectiveness, compatibility, and charging efficiency of the available technologies.

Place, publisher, year, edition, pages
Elsevier Ltd, 2018
Keywords
Charging infrastructure, Charging technology, Electric bus, Public transport, Survey, Thematic analysis, Buses, Cost effectiveness, Demonstrations, Electric automobiles, Surveying, Surveys, Charging efficiency, Charging infrastructures, Conductive charging, Demonstration project, Project implementation, Bus transportation
National Category
Civil Engineering
Identifiers
urn:nbn:se:kth:diva-236561 (URN)10.1016/j.tra.2018.09.011 (DOI)000452941000027 ()2-s2.0-85054178236 (Scopus ID)
Funder
Swedish Energy AgencyVattenfall AB
Note

QC 20181127

Available from: 2018-11-27 Created: 2018-11-27 Last updated: 2019-01-03Bibliographically approved
Xylia, M. (2018). Towards electrified public bus transport: The case of Stockholm. (Doctoral dissertation). KTH Royal Institute of Technology
Open this publication in new window or tab >>Towards electrified public bus transport: The case of Stockholm
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis addresses the challenge of road transport electrification using a systems approach for the particular context of Stockholm’s public transport system. The objective is to identify the benefits of large-scale bus electrification on energy efficiency and greenhouse gas emissions, as well as the cost and planning considerations required for achieving such a shift. Quantitative and qualitative methods are deployed for answering the research questions, including the development and use of an optimisation model, survey research, and interviews. 

The results of the optimisation model developed for this thesis show that an optimal system configuration is obtained with a combination of electricity and biodiesel. The high energy efficiency of electric buses would lead to a significant reduction of energy consumption in Stockholm, even if not all bus routes in the network are electrified. Although larger battery capacities could support the electrification of more bus routes, this does not necessarily lead to lower environmental impact. In any case, electricity from renewable sources should be used to maximise emission reductions. 

The results also show that the annual costs necessary to invest in electric buses can be balanced by lower fuel costs. An effective utilisation of the charging infrastructure is of high priority in order to justify the costs of the required investments. The model results confirm the benefits of creating a dense initial network of charging stations in the inner city’s public transport hubs, which would facilitate the electrification of multiple routes and high infrastructure utilisation at lower costs. 

The survey and interviews with stakeholders indicate that multiple issues affect the choice of charging technology, not just costs. Compatibility, reliability, bus dwell time, as well as weather conditions and visual impact are some of the additional aspects taken into account. The introduction of electricity tax exemption for electric buses, the expansion of the electric bus premium to include private stakeholders, as well as the expansion of infrastructure investment subsidy programmes are among the policy instruments suggested for assisting a faster introduction of electric buses into Stockholm’s public transport system. 

Although the focus is on Stockholm, the conclusions of this work can be applicable to other cities in Sweden and around the world, which also face the challenge of making public transport a more sustainable option.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2018. p. 77
Series
TRITA-ECS Report ; TRITA-ECS Report 18/02
Keywords
electric bus; charging infrastructure; optimisation; public transport; fossil-free; transport planning; Sweden
National Category
Energy Engineering
Research subject
Energy Technology
Identifiers
urn:nbn:se:kth:diva-226518 (URN)978-91-7729-742-0 (ISBN)
Public defence
2018-05-16, E2, Lindstedtsvägen 3, 13:00 (English)
Opponent
Supervisors
Funder
Swedish Energy AgencyThe Swedish Knowledge Centre for Renewable Transportation Fuels (f3)Integrated Transport Research Lab (ITRL)
Available from: 2018-04-19 Created: 2018-04-18 Last updated: 2018-05-15Bibliographically approved
Xylia, M., Silveira, S., Duerinck, J. & Meinke-Hubeny, F. (2018). Weighing regional scrap availability in global pathways for steel production processes. Energy Efficiency, 11(5), 1135-1159
Open this publication in new window or tab >>Weighing regional scrap availability in global pathways for steel production processes
2018 (English)In: Energy Efficiency, ISSN 1570-646X, E-ISSN 1570-6478, Vol. 11, no 5, p. 1135-1159Article in journal (Refereed) Published
Abstract [en]

This study analyses the impact of the rising availability of steel scrap on the future steel production up to the year 2100 and implications for steel production capacity planning. Steel production processes are energy, resource, and emission intensive, but there are significant variations due to different production routes, product mixes, and processes. This analysis is based on the development of steel demand, using the Steel Optimization Model, which provides a region-detailed representation of technologies, energy and material flows, and trade activities. It is linked to the Scrap Availability Assessment Model which estimates the theoretical steel scrap availability. Aggregated crude steel production is estimated to evolve into an almost balanced split by 2050 between the primary production route using iron ore in the blast oven furnace and the secondary route using mostly steel scrap in the electric arc furnace. By 2060, the share of secondary steel production will exceed the share of primary steel production globally. The results also estimate a global increase in scrap use from 611 Mtonnes in 2015 to 1500 Mtonnes in 2050, with the highest growth being for post-consumer scrap. In 2050, almost 50% of post-consumer scrap is expected to be traded, with the main exporter being China and major importing regions being Africa, India, and other developing Asian countries. The results provide valuable insights on scrap availability and capacity development at the regional level for producers contemplating new investments. Regional availability, quality, and trade patterns of scrap will influence production route choices, possibly in favor of secondary routes. Also, policy instruments such as carbon taxation may affect investment choices and favor more energy-efficient and less carbon-intensive emerging technologies.

Place, publisher, year, edition, pages
Springer, 2018
Keywords
Steel production, Steel scrap, Material flow analysis, Energy efficiency, Energy modeling
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:kth:diva-230485 (URN)10.1007/s12053-017-9583-7 (DOI)000432748200006 ()2-s2.0-85034818690 (Scopus ID)
Note

QC 20180614

Available from: 2018-06-14 Created: 2018-06-14 Last updated: 2018-06-14Bibliographically approved
Xylia, M., Leduc, S., Patrizio, P., Silveira, S. & Kraxner, F. (2017). Developing a dynamic optimization model for electric bus charging infrastructure. In: Transportation Research Procedia: . Paper presented at 20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest, Hungary (pp. 776-783). Elsevier, 27
Open this publication in new window or tab >>Developing a dynamic optimization model for electric bus charging infrastructure
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2017 (English)In: Transportation Research Procedia, Elsevier, 2017, Vol. 27, p. 776-783Conference paper, Published paper (Refereed)
Abstract [en]

Urban regions account for 64% of global primary energy use and 70% of carbon emissions. For that reason, options to decarbonize urban environments are receiving increasing attention. In this context, public transport shall play a key role in decarbonizing urban road transport. One efficient way to achieve that is shifting towards clean fuels and modern electric buses, an option that is already under implementation in several cities around the world. In this paper, the basis for developing a dynamic optimization model for establishing charging infrastructure for electric buses is presented, using Stockholm, Sweden, as a case study. The model places constraints depending on the bus stop type (end or middle stop) which affects the time available for charging at each particular location. It also identifies the optimal technology type for the buses: conductive or inductive. In addition, the electric buses compete with buses run on biogas or biodiesel. In this paper, we present the results of a cost minimization scenario with constraints placed on the available charging time and power, differentiated between end stops and major public transport hubs. The mean charging time is 7.33 minutes, with a standard deviation of 4.78 minutes for all bus stops. The inner city bus routes require less charging time, which ranges on average at around 3 minutes. The installation of chargers at the locations proposed in the model would require scheduling adjustments and careful planning for the density of charging occasions.

Place, publisher, year, edition, pages
Elsevier, 2017
Series
Transportation Research Procedia, ISSN 2352-1457 ; 27
Keywords
charging infrastructure, electric bus, Mixed Integer Linear Programming, optimization, public transport, Sweden
National Category
Transport Systems and Logistics
Identifiers
urn:nbn:se:kth:diva-223095 (URN)10.1016/j.trpro.2017.12.075 (DOI)2-s2.0-85039946918 (Scopus ID)
Conference
20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest, Hungary
Note

QC 20180214

Available from: 2018-02-14 Created: 2018-02-14 Last updated: 2018-04-18Bibliographically approved
Xylia, M., Ibrahim, O. & Silveira, S. (2016). Fossil-free Public Transport: Prescriptive Policy Analysis for the Swedish Bus Fleets. In: 13th European Energy Market Conference -EEM 2016. IEEE XPlore: . Paper presented at 13th European Energy Market Conference -EEM 2016. IEEE conference proceedings
Open this publication in new window or tab >>Fossil-free Public Transport: Prescriptive Policy Analysis for the Swedish Bus Fleets
2016 (English)In: 13th European Energy Market Conference -EEM 2016. IEEE XPlore, IEEE conference proceedings, 2016Conference paper, Published paper (Refereed)
Abstract [en]

Elicitation and processing of the relevant informationis the core of any policy decision-making process. This studypresents a prescriptive policy analysis for the “fossil-free fueldeployment for public transport buses at the national level inSweden”, using a policy-oriented modelling and simulation tool,Sense4us1, that supports systems analysis for policy involving: (i)structuring of policy problems using the labelled causal mappingmethod, (ii) ex-ante impact assessment using scenario-baseddynamic simulation modelling and (iii) ex-ante evaluation of theconsidered policy options based on the simulation results andusing a set of standard criteria for evaluation of EU policyinterventions. The results are most of all useful for designing apolicy pathway for public bus transport that is bothenvironmentally sustainable and economically feasible.Moreover, the process allows involvement of the keystakeholders to reflect various priorities and preferences.

Place, publisher, year, edition, pages
IEEE conference proceedings, 2016
Series
International Conference on the European Energy Market, ISSN 2165-4077
Keywords
Policy analysis, labelled causal mapping, Multi- Criteria Decision Analysis, public transport, bus, Sweden
National Category
Energy Systems
Research subject
Planning and Decision Analysis
Identifiers
urn:nbn:se:kth:diva-185750 (URN)000382910700090 ()2-s2.0-84983297493 (Scopus ID)978-1-5090-1298-5 (ISBN)
Conference
13th European Energy Market Conference -EEM 2016
Note

QC 20161011

Available from: 2016-04-26 Created: 2016-04-26 Last updated: 2016-10-11Bibliographically approved
Xylia, M., Silveira, S. & Morfeldt, J. (2016). Implications of an energy efficiency obligation scheme for the Swedish energy-intensive industries: an evaluation of costs and benefits. Energy Efficiency, 1-19
Open this publication in new window or tab >>Implications of an energy efficiency obligation scheme for the Swedish energy-intensive industries: an evaluation of costs and benefits
2016 (English)In: Energy Efficiency, ISSN 1570-646X, E-ISSN 1570-6478, p. 1-19Article in journal (Refereed) Published
Abstract [en]

The EU Energy Efficiency Directive (EED) aims at improving energy efficiency by implementing actions in all sectors of the economy in the EU. Article 7 of the EED sets the target of 1.5 % cumulative annual energy end-use savings. An energy efficiency obligation scheme (EEO) is one of the policy mechanisms proposed to reach this target. This paper assesses the impact of implementing a Swedish EEO and the implications that such a scheme may have for Swedish energy-intensive industries. The assessment was based on cost-benefit analysis (CBA) methodology. The benefit-to-cost ratio (BCR) ranges from 1.56 to 2.17 and the break-even cost ranges from 83.3 to 86.9 €/MWh with sensitivity analyses performed for the emission allowance prices and eventual costs of the EEO. The annual energy savings potential is estimated to be 1.25 TWh/year. A Swedish EEO could motivate investments in energy efficiency measures and thus help Sweden reach the energy efficiency targets set in the EED.

Place, publisher, year, edition, pages
Elsevier, 2016
Keywords
Energy efficiency obligation scheme, Cost-benefit analysis, Industrial energy efficiency, Energy efficiency directive, Sweden
National Category
Energy Systems
Research subject
Energy Technology
Identifiers
urn:nbn:se:kth:diva-185749 (URN)10.1007/s12053-016-9446-7 (DOI)000394263100009 ()2-s2.0-84964240147 (Scopus ID)
Note

QC 20161010

Available from: 2016-04-26 Created: 2016-04-26 Last updated: 2017-11-30Bibliographically approved
Xylia, M. (2016). Is energy efficiency the forgotten key to successful energy policy?: Investigating the Swedish case. (Licentiate dissertation). Stockholm: KTH Royal Institute of Technology
Open this publication in new window or tab >>Is energy efficiency the forgotten key to successful energy policy?: Investigating the Swedish case
2016 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Sweden aims to become one of the first fossil-free welfare countries in the world. In 2009, specific energy and climate policy targets were announced for 2020, which exceed the ambition of respective EU targets in some areas. The overarching objective of the thesis is to understand the role of energy efficiency in Swedish energy and climate policy frameworks, and identify the gaps that need to be addressed. In this context, energy efficiency is recognized as a challenge to address. Yet, there are reasons to believe that it is not being pursued with the same dedication as other energy and climate-related targets.

This hypothesis is tested using Mixed Methods research, with cases on different sectors of the Swedish economy, namely energy intensive industry and public bus transport, as well as comparisons with energy efficiency within the EU-28. With the help of abductive reasoning, the observations are inferred to an explanation, and common themes for Swedish energy efficiency policies emerge.

The evidence indicates that energy efficiency has received lower priority than other energy and climate policies. This is demonstrated by the conflict between energy efficiency, emission reduction and renewable energy targets, for example in the case of public transport. There is generally a mismatch between targets and the instruments in place. Thus more attention should be given to energy efficiency and its potential benefits for the Swedish energy system.

Opportunities for energy efficiency improvements are not being fully realized, but new policy initiatives could provide the necessary support to harness the potential. In-depth evaluation of new policy instruments should be integrated in the policy-making process, in order to provide a clear picture of costs versus benefits. An example is given with a Cost-Benefit Analysis for energy efficiency obligations targeting the Swedish energy intensive industry.

Simplicity and transparency in the introduction and monitoring of new instruments need to be sought for. Energy efficiency should be given first priority in relation to other energy and climate targets. The basis for future policies should be grounded now in order for energy efficiency to become the key for successful Swedish energy policy. 

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2016. p. 62
Series
TRITA-ECS Report ; 16/01
Keywords
energy efficiency, energy policy, Sweden, policy research, mixed-methods research, Cost-benefit analysis, energy intensive industries, public transport
National Category
Energy Systems
Research subject
Energy Technology
Identifiers
urn:nbn:se:kth:diva-192291 (URN)978-91-7729-117-6 (ISBN)
External cooperation:
Presentation
2016-10-06, B2, Brinellvägen 23, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20160914

Available from: 2016-09-14 Created: 2016-09-08 Last updated: 2016-09-14Bibliographically approved
Xylia, M. & Silveira, S. (2016). Leading or lagging in the EU? Sweden’s progress towards energy efficiency targets for 2020. Energy Strategy Reviews
Open this publication in new window or tab >>Leading or lagging in the EU? Sweden’s progress towards energy efficiency targets for 2020
2016 (English)In: Energy Strategy Reviews, ISSN 2211-467X, E-ISSN 2211-4688Article in journal (Refereed) Submitted
Abstract [en]

Sweden aims at becoming one of the first fossil-free welfare countries in the world. In line with that goal, ambitious energy and climate targets were announced in 2009. The focus of this paper is energy efficiency, since its progress towards the 2020 target lags in relation to the other energy and climate policy targets. Statistical methods for time series analysis are applied in order to compare the country’s performance in comparison to the EU-28 average and explore the potential development of energy use at national and sectoral level in the years up to 2020. The results show that Swedish progress with energy efficiency does not stand out within the EU-28, in contrast with other energy and climate targets. The trend analysis also shows that it is uncertain whether the targets for 2020 will be achieved. Energy intensity may not be the most appropriate indicator for monitoring energy efficiency improvement, and absolute final energy savings should be used instead. The analysis for the three main Swedish end-use sectors shows decreasing final energy use trends in the past ten years.  However, none of the sectors is expected to show strongly decreasing trends in the upcoming years. In order to enhance the role of energy efficiency in energy and climate policy, its contribution in reducing emissions should be clarified and promoted. Finally, increased simplicity and transparency should be established when setting targets for energy efficiency and monitoring progress.

National Category
Energy Systems
Research subject
Energy Technology
Identifiers
urn:nbn:se:kth:diva-192523 (URN)
Note

QC 20160927

Available from: 2016-09-14 Created: 2016-09-14 Last updated: 2017-11-21Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-2896-8841

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