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 city of Uppsala is suffering from power shortage, which is creating issues for Region Uppsala, which manages the new city bus depot. Gamla Uppsala Buss (GUB), the operator of the city busses, has bought 12 electrical busses and is planning to increase that number up to 60, which is a political goal. Charging of the electrical busses occurs mostly in the nights, but also during lunch time. In this thesis, scenarios of how different number of buses (12, 36 and 60) relates to the power subscription limit at the depot is studied. The study was made through interviews with industry experts and by creating different scenarios in an Excel-model which was produced in this work. One main conclusion from the interview study was that the regulation control of all the technical components of the system, and foremost the regulation control of the charging of the busses, is a vital component to handle the charging properly. Optimal regulation control requires accurate planning and advanced calculations which relies upon access of data, i.e., charging cycles, battery range and electric energy consumption. The simulations in the Excel-model showed that the bus depot could handle 12 electrical buses with the available power subscription that is today. For 36 or 60 electrical busses additional power had to be added behind-the-meter, which could be obtained with energy storage (batteries), a biogas engine linked to a generator or a combination of those two. The simulations showed that either an energy storage or a biogas engine could compensate for the lack of power, with reasonable proportions. The two technical solutions could also be combined in infinite ways, depending on the goal of Region Uppsala, to fulfill the task. The technical solution that is most feasible for Region Uppsala depends on their priorities. The economics of the solution will of course be a big factor, which has not been included in this work. Another feasible priority could be to choose a technical solution that creates utility for the power system of Uppsala, i.e., mitigating power shortage, with a solution that has a high selfproduction of electric energy and a power consumption profile of the bus depot that is inverted to the rest of the city’s.