The European Commission states that transport is the second largest greenhouse gas-emitting sector and accounts for 25% of all greenhouse gas emissions in the European Union (EU). Light duty vehicles including cars and vans produce around 15% of the EU’s emissions of carbon dioxide (CO2), which is the main greenhouse gas. The introduction of mass produced highway capable electric vehicles (EV’s), also referred to as electric, to the retail market since 2014, will contribute to the mix of initiatives and incentives aimed at achieving the key targets of the 2020 Climate and Energy package, which was legislated in 2009 to ensure the EU meets its climate and energy targets in 2020. As the uptake of electric cars intensifies, electricity grid infrastructure will require reinforcement and upgrading. Distribution service operators (DSO’s) will need to understand and prepare in advance for the impact electric cars will have on the low voltage grid.
This thesis presents the current state of electric car technology based on literature review; and investigates the possible impact of electric car charging on low voltage grids. As a case study, the low voltage grid of a localised district of Budapest is modelled using DIgSILENT PowerFactory, which is a power system analysis software tool. With the aid of this model, the impact of electric cars is analysed. The aforementioned district is characterised by predominately low to medium density residential dwellings, where private off-street parking is available to facilitate the charging of electric cars from a conventional single-phase household power outlet. The modelling indicates that with uncontrolled charging and at a level of 20% uptake of electric cars among household consumers, the low voltage grid infrastructure will operate well within the normal operating limits.
The implication of this thesis work suggests that at least up to 20% penetration, the impact of uncontrolled charging of electric cars on the low voltage grid will not present any significant consequences; and that DSO’s have time to thoughtfully plan and implement strategies that will facilitate a more intensive and widespread rollout of electric cars in the future.