Abstract
Factors such as the increasing oil price and the environmental impact of internal combustion engines (ICE) have raised the interest of politicians and vehicle manufacturers in electric drive technologies powered by batteries. Hybrid drives are already a reality in the European automotive market, however, the expected evolution in this field suggests that plugin electric vehicles (EV) will be the next step. This means a major change in road transport, since EVs (hybrid, extended range, full electric) will obtain part or their entire energy requirement from the distribution network. Therefore, the charging infrastructure, including the electrical grid, will be closely related to EVs on their way towards a successful market development in the future.
It is clear that electric vehicles will have an impact on electrical grids. Nevertheless, it is up to all of us to make that impact positive for the network, which, by the way, is much related to a positive environmental, economical and social impact. On the one hand, the greenhouse gas emission level due to the operation of electric vehicles is directly related to the energy generation mix that supplies the grid during charging periods (unless storage is used). On the other hand, if the EV charging would take place during the electrical system demand peaks, that would raise its stress. A gradual penetration of EVs would make possible to upgrade the electrical infrastructure to face the demand increase, but with the social and environmental impact associated to network extension (infrastructure cots, land occupation, etc.) and under the risk of system oversizing, due to an enhancement of the difference between valley and peak demands (infrastructure costs, higher energy requirements, etc.).
The present paper will focus on the work carried out on this last aspect. The impact of EVs demand on part of the Spanish electrical network has been assessed for different penetration levels and charging strategies. Simulations have been carried out to show how EVs may affect the electrical system under each scenario. The first conclusion is that smart charging of vehicles is necessary, up to a certain level, to evolve towards a future in which EVs will support a more sustainable society from the environmental, economical and social points of view. This would surely permit the development of EVs market to become a success story, fostered by the evolution of current electrical systems towards the smartgrid of the future, a framework in which new technologies and appropriate business models will help create this historical change in the world of road transport.
Keywords — Electric Vehicle, Distribution Grid, Environmental Impact, EV market