Elektrifiering av personbilar på Tomtebo, Umeå : Electrifications of passenger cars at Tomtebo, Umeå

Sammanfattning: In the future, new fuels will be sought to minimize the carbon footprint on Earth. With electric vehicles becoming a growing trend there is an annual increase in hybrid and electric cars, even electrified buses have become more convenient. The new electric vehicles will then be a load on the electricity grid when recharging is required, sometimes during the sensitive hours of the day where other power requirements are greater. The purpose of this thesis was to gain a deeper understanding of how the Swedish electricity grid is structured and also answer the questions if the area named Tomtebo will be able to handle an electrification of passenger cars, and also what the power forecast will look like. An excel model, developed by Sweco, is used for the calculations and later on there is an evaluation of this model if it can be applied to smaller areas and if any improvements can be made towards it. The electric car load on the electricity grid is based on three possible scenarios referred from a report by Sweco and using the excel model to calculate the power requirement of the three scenarios with different traffic works on electricity. Scenario one corresponds to today's electrification degree on traffic work, scenario two corresponds to double electrification degree on traffic work and in scenario three, a full electrification as well as a new traffic hierarchy with more public transports will be used, according to the report by Sweco, resulting in less power requirements for traffic. In all three scenarios, it is assumed that the electric car will be charged at night with a charging power of 2.3 kW, this corresponds to charging directly from power outlet. Tomtebo is a residential area that is being expanded and is expected to grow in the coming years and the population there are mostly younger families, which gives the probability of investment of a fossil-free passenger car increase. In order to estimate the proportion of electric cars for the area, Statistics Sweden and Region facts have been used to estimate the amount of cars at Tomtebo. In Umeå there is a total of 1,400 electric cars and 95 of these were likely to be at Tomtebo. Out of this amount there is plugin hybrids, PHEV, and pure electric cars, BEV, which gave a distribution 75/25 percent according to data from national statistics. With a known number of cars, an itinerary was required which could be probable around twenty kilometers. In the Excel model, values were applied for scenario one, which gave the power requirement for the 95 cars a total of 18 kW per hour. With a grid that has a total power up to 3.7 MW per hour then the cars' power requirements are a minimal burden towards it, furthermore an equivalent result came from both scenarios two and three. With these three results came the conclusion that with the amount of cars available there today no major load was done on the electricity grid and thus a greater number of cars were required. Umeå aims to reach 200,000 inhabitants by the year of 2050, which would then give Tomtebo 12,000 residents and this would result in an estimated 6,100 cars there. Of these with today's distribution there would then be 200 electric cars but since this scenario is so far ahead in the future it was assumed that all vehicles in 2050 would be an electric car, which then leads to it being fully electrified at Tomtebo. The 6,100 electric cars power provided 6 MW of total power demand for today's electricity grid, which means that it won’t work in the future. To find the breaking point for how many electric cars the gird can handle it was assumed that all Tomtebo's cars today, corresponding to 3,780 cars, would be electric cars and by moving the charge schedule to early morning, when the demand was much lower, the result gave that the grid could handle about that many cars. What is important to understand is that the electricity grid does not have a maximum ceiling for demand, but it all works about equilibrium where one strives for a consistent power balance on all iv hours of the day. If the consumers need more power then the electricity companies transfer it but an under-dimensioned infrastructure can put a stop to this which might be the case in the future. When the question whether Tomtebo's electricity grid can handle the load, the answer is that a full electrification of Tomtebo is entirely possible but that future investments are something that should be reviewed. This result from the excel model using the parameters and assumptions reflects the reality. The difficult thing about using the model in my opinion is the estimation of car numbers where in a city like Umeå where there does not exist any cameras or registers of which car type is moving where, which it does on others places, such as Gothenburg and Stockholm. Furthermore, there are thoughts about the design of the model as well also the question of the depth of battery but this is left out here but can be read under the relevant section. What controls how quickly a changeover from fossil-fueled to non-fossil vehicles is the result of instruments where subsidies and taxation come into focus, then of course laws and regulations. What makes it so difficult to estimate what the future will look like in theory is that tomorrow can have a new law leaving only non-fossil vehicles.