Electric power systems are facing a major new challenge (and hence opportunity): the future massive integration into the electric grid of hybrid/pure electric plug-in vehicles (EV). The stimulus of this change is that electricity is likely to become the preferred energy vector for a new generation of road vehicles. Although conventional fossil fuels can be used to generate electricity to feed EV, this project will focus on the quantification of the allowable amount of renewable energies that can be integrated into the electric power system, as this is a more desirable option, which would greatly reduce CO2 emissions.
Distribution and transmission grids and power system architectures still follow planning rules and procedures defined for a traditional operating paradigm. The development of the SmartGrids concept will bring changes to power system planning and operation that will ease a large deployment of EV but full implantation of SmartGrids is still some time away.Therefore, it is necessary to identify and prepare solutions for the operational problems that will be caused on the electric grid, to the generation sub-system and to its commercial operation as a result of progressively increasing deployment of EV. These can be regarded either as a load (when charging) or a small energy producer (when injecting active power into the grid). When in charging mode, EV can lead to major congestion in already heavily loaded grids, or voltage profile problems, especially if the peak load times coincide with the EV charging periods. However, if a suitable management scheme is defined, predominantly valley hours can be used to charge EV and avoid the anticipated problems. Under the V2G concept, EV can also be used as dispersed energy storage devices that can provide ancillary services, decreasing the need for traditional reserve, helping to manage congestion by shaving peak loads and improving system dynamic behaviour in normal and emergency conditions.
There are two ways of accommodating the presence of EV battery charging in the distribution grids. The first is to plan for new networks in such way that they can fully handle the new loads, regardless of the control scheme, requiring heavy investment in network reinforcements to do so. The second is to create a smart management system that fully integrates EV in the power system, exploiting also the potential of EV as energy storage devices. The latter is, of course, the way that needs to be pursued.
Progressive replacement of conventional vehicles by EV will require two types of interfacing structures: a) charging stations used to charge fleets of EV or to charge EV that require fast charging, including replacement battery changing, or b) domestic or public individual charging/grid interface points for slower charging. Both cases will be considered.
This project will evaluate the impacts that EV will have on the EU electric power systems regarding planning, operation and market functioning. The focus will be placed on EV and SmartGrid/microgrid simultaneous deployment, together with renewable energy increase, leading to CO2 emission reduction through the identification of enabling technologies and advanced control approaches.