The impact of an Electrification of Road Transportation on the Electricity system in Scandinavia
Licentiate thesis, 2017
The transport sector needs to reduce CO2 emissions by replacing fossil fuels with low-carbon options. An electrification of the road transport sector through electric vehicles (EVs) with static charging; electric road systems (ERS); and using electricity to produce a fuel, are all suggested as possible options. An electrification of the transport sector introduces a new demand to the electricity system, and hence, will create new load profiles depending on the time of consumption and the amount of electricity used in EVs. Depending on electrification strategy, this new demand may introduce a potential for EVs to provide demand-side management to the power grid. The overall aim of this work is to investigate how an electrification of the transport sector could impact the Scandinavian electricity system with respect to energy and power.
A vehicle energy consumption model was developed to estimate the variation of the energy and power demands with time and location for the transportation work on a highway under the assumption of different electrification options and drivetrains. Furthermore, demand for electric transportation have been included in electricity system models (a cost-minimizing investment model of the electricity system and one electricity system dispatch model) in order to investigate how EVs may impact the investment in new power capacity and integration of wind power in the Scandinavian and German electricity system by Year 2030.
Our results, using the Norwegian road E39 as an example, indicate that an electrification of road transport implies large variations in energy and power demand both over time and location, i.e. spatial and time distributions of demands, along the road. Installation of ERS on all the European (E) and national (N) roads in Sweden and Norway would cover more than 50% of the vehicle traffic. A 25% implementation of ERS out of the total E- and N-road sufficient in order to connect the larger cities in Norway and Sweden by ERS.
We have also shown that with a cap on CO2 corresponding to 93% emission reduction by Year 2050, the demand from EV in Scandinavia and Germany are mainly met by an increase in generation from wind power and to some extent coal in combination with carbon capture and storage. A smart integration of passenger EVs (vehicle-to-grid; V2G) can to some extent be used to manage variability of renewable energy sources by, for instance, substantially reduce the need for peak power capacity in the system. If using an indirect strategy for electrification of transportation, via for instance hydrogen or electrofuels, the annual electricity demand would increase more than four times compared to static or dynamic charging, albeit with increased flexibility to distribute such demand both geographically and in time. Further studies is needed to compare V2G with other storage technologies and demand side management strategies.
electric road systems
energy system modelling