Fossila drivmedel ger en negativ påverkan på miljö och klimat. Men frågan är om biodrivmedel är bättre. Det kan skilja stort mellan olika drivmedel beroende på vilken råvara och framställningsprocess som används. Syftet med studien är att göra en sammanställning av fördelar och nackdelar med olika fossilfria drivmedel som används och kan komma att användas i kollektivtrafiken i Gävleborgs län. I samråd med X-trafik, den regionala kollektivtrafikmyndigheten, har det framkommit att det främst är biodiesel (HVO - hydrogenerade vegetabiliska oljor), biogas och el som är intressanta att analysera. Rapporten kommer att redogöra hur användningen ser ut i andra delar av landet och i världen för att kunna anpassa kunskaperna till Gävleborgs län. I studien ingår även en granskning av produktionspotentialen för dessa drivmedel i länet. Det slutgiltiga resultatet av studien kommer att bidra till utvecklingen av en fossilfri fordonsflotta i regionen. Genom intervjuer med närproducenter av biogas (Gästrike Ekogas AB) och biodiesel (Colabitoil AB) samt med X-trafik inhämtades kunskap om hur produktionen ser ut i länet och vilka behov som finns. Detta tillsammans med en litteraturstudie gav resultatet. X-trafik har huvudansvaret för kollektivtrafiken och utför den genom entreprenörer som fått uppdragen genom upphandling. HVO har många fördelar mot andra dieselbränslen och kan tankas direkt i fordonen utan att dessa behöver modifieras. Dessutom görs den HVO som Colabitoil distribuerar och kommer börja producera på restavfall. En av X-trafiks entreprenörer har slutit ett avtal med Colabitoil vilket betyder att all fossil diesel som bussarna kör på idag kommer att bytas ut mot biodiesel. I Gävle stad kör bussarna på biogas och gasen produceras på avloppsreningsverket Duvbacken. Denna produktion täcker upp 60 % av behovet och resten är fossil gas. Med den nya anläggningen som Gästrike Ekogas håller på att bygga kommer behovet mer än väl täckas upp. Biogasen är även den gjord på restavfall. I den nya biogasanläggningen kommer de också få en utmärkt biogödsel fri från föroreningar, som kan KRAV-märkas och användas till odling för att ersätta konstgödsel. Elbussar är något som diskuteras av X-trafik och kan vara bra alternativ på vissa linjer dock är tekniken under utveckling fortfarande och investeringskostnaden är hög. Det finns potential att kollektivtrafiken i Gävleborgs län kan köra på 100 % miljövänligt, hållbara och närproducerade drivmedel inom en snar framtid. / The purpose of this study is to make a summary of the advantages and disadvantages of various non-fossil fuels that are used and can be used in public transport in the county. In consultation with X-trafik, it has emerged that it is mainly biodiesel (in the form of  HVO - hydrogenated vegetable oils), biogas and electricity that are interesting to analyse. The report will describe the use in other parts of the country and the world to adapt the knowledge to the county. The study also includes an investigation of the production potential of these fuels within the county. The final results of the study will contribute to the development of a fossil free fleet in the region. Through interviews with local producers of biogas (Gästrike Ekogas AB) and biodiesel (Colabitoil AB) and X-trafik information was collected about how the production is performed in the county and what the needs are. This, together with a literature review yielded the results. X-trafik has the main responsibility for the public transport and carries it out through contractors with assignments through procurement. HVO has many advantages compared to other diesel fuels and can be refueled directly in vehicles without modifications of these. Additionally, the HVO that Colabitoil distributes and will begin producing is made of residual waste. One of X-Trafik's contractors has signed a contract with Colabitoil which means that all fossil diesel the buses run on today will be replaced with biodiesel. In Gävle city the buses run on biogas and the gas is produced at the sewage treatment plant. This production covers 60% of the need and the rest is fossil gas. The new facility, which Gästrike Ekogas is building, will produce more than the public transport needs. Biogas is also made from residual waste. The new facility will also yield a by-product in the form of an excellent bio-fertilizer free of contaminants that can be KRAV labelled and used for cultivation to replace chemical fertilizers. Electric buses are something that is discussed, and may be a good option on certain routes, however, the technology is still under development and the investment cost is high. There is great potential that the public transport in the county can run on 100% eco-friendly, sustainable and locally produced fuels in the near future.

Region Uppsala, who are responsible for the public transport in Uppsala county, are currently building a new city bus depot. Due to capacity shortage in the transmission grid to Uppsala, the operation of the new bus depot must be adapted to a limited power output. In addition to this, the city of Uppsala aims to introduce the first electrical buses by 2021. The purpose of this study was to investigate how electrical buses of different penetration level will affect the power demand at the new city bus depot. The results showed that the current power limitation was already exceeded by 200 kW if 12 electrical buses were to be introduced. Therefore, different technical solutions were evaluated in terms of increasing the penetration level of electrical buses. These solutions were evaluated by a life cycle cost analysis. The cheapest solution was to connect the city bus depot with the regional bus depot. This is possible because the grid connection to the regional bus depot is oversized, compared to its load. However, this solution does not solve the general problem of capacity-shortage in Uppsala and the legality of it must be analyzed further. Two other solutions that were investigated were a local battery storage and a gas engine coupled with a generator at the depot. None of the solutions could solve the power problem at the depot on its own. For a scenario with more than 40 electrical buses, the different technical solutions that were investigated must be combined.

The Swedish government announced in 2015 that Sweden will work towards becoming "one of the first fossil-free welfare states of the world". The objective is to reduce the usage of fossil fuels by 70 percent by the year 2030 compared with the levels of 2010. Important factors to achieve this is to reduce the amount of transport, increase the use of biofuels and increase the fuel efficiency. The public transport sector plays an important part in reaching these objectives. There is a lot of potential in the biofuel market and in recent years there has been a development in the segment of electric buses in the city traffic. The purpose of the study is to develop a strategy proposal for the use of fossil-free fuels in Uppsala's public transport. The study is delimited to examine the use of fuels in city traffic with a focus on the introduction of electric buses. The report contains an environmental analysis of the advantages and risks associated with the fuels that the public transport administration UL decided to proceed with; biodiesel, biogas, and electricity. Based on the analysis, a strategy proposal was developed for how these fuels can be distributed in city traffic in Uppsala between 2019 - 2029. The study also examines how energy use, carbon dioxide emissions, and traffic pollution are affected if the strategy proposal is implemented. The environmental analysis suggests that biogas will continue to be used in Uppsala's city traffic, together with electric buses. Biodiesel is likely to come to better use in other areas of the transport sector in order for Sweden to reach the target of a fossil-independent fleet of vehicles in 2030. If the strategy proposal is followed the result shows that energy use and emissions of carbon dioxide and traffic pollution will decrease. Energy consumption will be reduced because of the energy efficiency of electric buses. The reduction of traffic pollution is due to the electric buses, but also because vehicles with the Euro V engine has been replaced with vehicles with Euro VI engine, which lowers traffic pollutions.

This thesis investigates the charging power and battery capacity needed for fast charging of fully electrical busses at end stations in Uppsala, Sweden. The operator, UL, wants to implement electrical busses by 2020 and a new depot for the city buses is being built with possibility to slow-charge the busses overnight. However, due to restrictions in the transmission grid the requested grid connection was denied by Vattenfall Eldistribution. Simulations in this thesis is based on the existing bus schedules for city bus route 6 and route 8 in Uppsala. The routes were selected by UL as suitable candidates for fast charging at end stations. Simulations were made with varying charging power, battery capacity and energy usage by the buses. A worst case-scenario was simulated to ensure that the solution would work even in bad weather conditions. The results show that it is possible to dimension the battery to match the current time schedule. The battery capacity needed depends on charging power, length of route and time available for charging. With 300 kW charging power, the battery capacity needed to manage the bus schedule during weekends were higher than during weekdays. Furthermore, the needed battery capacity for weekends on route 8 were significantly higher than for route 6. If the whole bus fleet would be electrified, the choice of charging technique and battery size depends on the routes and passenger capacity needed. A combination of different charging techniques may be the most efficient solutions when the whole bus fleet is considered.

Enligt (Regeringskansliet, 2017a) ska nettoutsläppen från Sveriges växthusgaser år 2045 inte påverka atmosfären vartefter Sveriges utsläpp ska bli negativa, vilket innebär att det används mer koldioxid än vad som släpps ut. För att uppnå klimatmålen kommer det krävas många nya lösningar i samhället. En allt mer drivande transportsektor med mer bilar på vägarna och fler parkeringsplatser är inte hållbart för framtida svensk trafik och arbetet mot klimatmålen. Att avlägsna oljedrivna fordon från transportsektorn skulle bidra till ett renare och mer attraktivt stadsklimat.   Studien syftar till att ta reda på hur en implementering av elektrisk-, även självkörande kollektivtrafik i Varberg ser ut, energimässigt, miljömässigt och ekonomiskt för tre stycken upplagda scenarier. I studien ingår även att undersöka ifall övertoner kan komma att inverka på elnätet. Projektet som är ett samarbete med Varberg Energi har uppkommit i samband med planeringen av det nya stadsområdet Västerport. I scenarierna finns tre olika bussar: en dieselbuss som återfinns i Varberg idag, en generell elbuss samt en självkörande elbuss som kallas Navya.   Den mängd passagerare som ska transporteras och vilken miljöpåverkan bussarna ger har stor inverkan på slutsatsen i rapporten. Med en svensk fossilfri bussflotta år 2020 visar denna rapport att Navyan är primärt rekommenderad upp till 15 personer och därefter är elbussen sekundärt rekommenderad. Implementering av elbussar är fullt möjlig och gör ingen betydande inverkan på det befintliga elnätet idag. / According to (Regeringskansliet, 2017a) Sweden’s greenhouse gas emissions shall not affect the atmosphere by the year 2045, which then becomes negative, this means that more carbon dioxide will be consumed rather than released into the atmosphere. In order to reach the climate goals, many new solutions to the society are required. A bigger transport sector with more cars and parking spaces is not sustainable for neither the future transport sector, nor the progressive work toward the climate goals. By removing oil-operated vehicles from the streets, a significant contribution to a cleaner city climate would be achieved.   The study aims to find out if an implementation of electric buses is possible in Varberg. A couple of key questions are raised: how much energy is required to support the buses? What are the costs of the various scenarios proposed? Will there be any problems with supporting many buses, in terms of harmonics and the electric power grid? The project, which is a cooperation with Varberg Energi, is proposing a realization of a new city area called Västerport, which would start construction 2020. The report constitutes three scenarios with a diesel bus, which is used in Varberg today, an electric bus and an autonomous electric minibus called Navya.   The number of passengers to be transported and the environmental effect of the buses has a big impact on the conclusion of the report. With a fossil free bus fleet by 2020, this report shows that the Navya is primarily recommended up to 15 passengers, and the electric bus for more passengers. The report concludes that the implementation of electric buses is possible. It will not have a considerable impact on the existing power grid and will contribute to a cleaner and more attractive city.

Battery electric vehicles and fuel cell vehicles, i.e. hydrogen vehicles, are promising alternatives to internal combustion engine vehicles to reduce GHG emissions from the transport sector. EV charging and hydrogen refuelling infrastructure is crucial to the deployment of alternative fuels in transport. Although several studies have analyzed electric public buses infrastructure, fuel cell buses have not been the target of such extensive analyses. Additionally, there is a gap in the literature regarding the comparison of infrastructure for these two types of vehicles and their cost and refuelling schedule differences. The study aims to conduct a techno-economic analysis of electricity versus hydrogen refuelling infrastructure to decarbonize public buses, using renewable sources to produce renewable electricity and green hydrogen. The outcome is a proposed system design regarding the size of the refuelling station, storage system capacity, renewable energy capacity, on-site hydrogen production system size, and the optimized refuelling schedule. The system is modelled to minimize the overall system cost while maintaining the current bus service level. The impact of electricity market prices, demand charges and varying bus energy demand in the optimal system configuration and schedule is also addressed. Scenarios are developed to study different levels of new installed renewable capacity integration and how these affect the cost, bus refuelling schedules and infrastructure design. The mixed-integer linear programming problem was modelled using Python. The model is applied to the case study of one bus line in Umeå. One terminal station was chosen to place the refuelling stations. The results show that the most economical option is electrifying the line with electricity supply only from the grid. For scenarios with additional renewable energy capacity installed, the option with 50% integration of new installed capacity is the most economically viable. In both these cases, there is no installation of BESS at the charging station. Electric buses infrastructure is cheaper than hydrogen infrastructure in all scenarios, but these values converge as renewable energy integration increases. For hydrogen infrastructure, the scenario with 50% renewable energy integration is the least costly. Although electric bus infrastructure is more economical than hydrogen infrastructure, hydrogen buses present advantages in terms of significantly higher range and thus higher flexibility for refuelling. Therefore, in the decision-making process to replace a fossil fuel bus line with an alternative fuel bus line, one must consider the multi-dimensional level of the different options. / Batterielektriska fordon och bränslecellsfordon, dvs. vätgasfordon, är lovande alternativ till fordon med förbränningsmotorer för att minska växthusgasutsläppen från transportsektorn. Infrastruktur för laddning av elfordon och tankning av vätgas är avgörande för att alternativa bränslen ska kunna användas inom transportsektorn. Även om flera studier har analyserat infrastrukturen för offentliga elbussar har bränslecellsbussar inte varit föremål för sådana omfattande analyser. Dessutom finns det en lucka i litteraturen när det gäller jämförelsen av infrastruktur för dessa två typer av fordon och deras skillnader i fråga om kostnader och tankningsschema. Syftet med studien är att genomföra en teknisk-ekonomisk analys av infrastruktur för tankning av el respektive vätgas för att avkarbonisera offentliga bussar, med hjälp av förnybara källor för att producera förnybar el och grön vätgas. Resultatet är ett förslag till systemutformning med avseende på tankstationens storlek, lagringssystemets kapacitet, kapaciteten för förnybar energi, storleken på systemet för vätgasproduktion på plats och det optimerade tankningsschemat. Systemet modelleras för att minimera den totala systemkostnaden samtidigt som den nuvarande service nivån förbussarna bibehålls. Effekten av elmarknadspriser, efterfrågeavgifter och varierande energiefterfrågan från bussarna på den optimala systemkonfigurationen och schemat behandlas också. Scenarier utvecklas för att studera olika nivåer av nyinstallerad förnybar kapacitet och hur  dessa påverkar kostnaden, bussarnas tankningsscheman och infrastrukturens utformning. Det linjära programmeringsproblemet med blandade heltal modellerades med hjälp av Python. Modellen tillämpas på fallstudien av en busslinje i Umeå. En ändstation valdes ut för att placera tankstationerna. Resultaten visar att det mest ekonomiska alternativet är att elektrifiera linjen med elförsörjning endast från nätet. För scenarier med ytterligare installerad kapacitet för förnybar energi är alternativet med 50 % integrering av ny installerad kapacitet det mest ekonomiskt lönsamma. I båda dessa fall finns det ingen installation av BESS vid laddningsstationen. Infrastrukturen för elbussar är billigare än infrastrukturen för vätgas i alla scenarier, men dessa värden närmar sig varandra när integrationen av förnybar energi ökar. När det gäller vätgasinfrastruktur är scenariot med 50 % integrering av förnybar energi det minst kostsamma. Även om infrastrukturen för elbussar är billigare än infrastrukturen för vätgasbussar har vätgasbussar fördelar i form av betydligt större räckvidd och därmed större flexibilitet när det gäller tankning. I beslutsprocessen för att ersätta en busslinje med fossila bränslen med en busslinje med alternativa bränslen måste man därför ta hänsyn till de olika alternativens flerdimensionella nivå.

Controlling the balance of production and consumption of electricity will become increasingly challenging as the transport sector gradually converts to electric vehicles along with a growing share of wind power in the Swedish electric power system. This puts greater demand on resources that maintain the balance to ensure stable grid operation. The balancing act is called frequency regulation which historically has been performed almost entirely by hydropower. As the power production becomes more intermittent with renewable energy sources, frequency regulation will need to be performed in higher volumes on the demand side by having a more flexible consumption. In this report, the electrification of 17 buses Svealandstrafiken bus depot in Västerås has been studied. The aim has been to assess different charging strategies to efficiently utilize the available time and power but also to investigate if Svealandstrafiken can participate in frequency regulation. A smart charging model was created that demonstrated how smart charging can be implemented to optimize the charging in four different cases. The simulated cases were: charging with load balancing, reduced charging power, frequency regulation, and electrifying more buses. The results show that the power capacity limit will be exceeded if the buses are being charged directly as they arrive at the depot and without scheduling the charging session. By implementing smart charging, Svealandstrafiken can fully charge the 17 buses within the power capacity limit of the depot with 82 minutes to spare. By utilizing this 82-minute margin in the four different charging strategies, it was found that Svealandstrafiken can save 88 200SEK per year by load balancing, save 30 000 SEK per year by reducing the charging power by 10 %, earn 111 900 SEK per year by frequency regulation or electrify five more buses. Reducing the charging power may also increase the lifetime of the batteries but quantifying this needs further studies. Conclusively, there is economic potential for Svealandstrafiken for implementing smart charging.