A Virtual Power Plant Management Model Based on Electric Vehicle Charging Infrastructure Distribution

The exploitation of distributed generation based on intermittent renewable energy sources (RES) has increased the load and generation profile variability. The resort to distributed energy storage systems (DESSs) is usually proposed to compensate the volatility introduced by RES. In particular, plugin electric vehicles (EVs) are considered one of the most interesting solutions for providing DESSs with the aim of exploiting RES production and matching the distributed electrical generation to the local demand. The aim of this paper is to analyze the impact of vehicle-to-grid technology on an weakly interconnected Virtual Power Plant (VPP) in order to evaluate the effects that distribution and availability of EVs charging structures can have on VPP total cost. A novel mathematical modeling of the mobility system is firstly developed to calculate the probabilistic distribution of parking places. Thereafter, the economic impact on a VPP has been evaluated for different plugin ratio and charging station scenarios

Management of distributed energy resources in energy systems

This thesis investigated the use cases of Electric Vehicles (EV) and stationary battery storage in a multi-level energy system with high penetration of renewable DER. The different energy system levels considered include large and local level, distribution network and customer premises. The reduction of excess electricity due to high shares of renewable energy technologies by using EV with Vehicle to Grid capability in a future GB energy system was investigated. It was found that with EV in vehicle to grid mode integrated into the energy system, the utilisation of fluctuating wind power was increased. This was realised by minimising the curtailment of excess electricity and CO2 emissions. Also in a local energy system with a high share of intermittent renewable energy, EV with Vehicle to Grid capability can reduce electricity import of about 34%. A microgrid was modelled for evaluating the impact of electrical vehicle charging on voltage profiles and energy losses in a local distribution network with a high share of distributed energy resources. The results show that with a smart charging scheme, the voltage profiles remain within distribution network operator’s defined limit. A reduction of energy losses in the microgrid was also noted. An optimisation tool using an optimisation technique was developed for optimising charging and discharging of a stationary battery storage. This was simulated to evaluate the revenue streams for an existing photovoltaic generation system. The key benefit of the photovoltaic generation system to the owner is the ability to maximise feed in tariff revenue streams by maximising self-consumption using a wholesale electricity tariff. The impact of storage unit cost on the adoption of battery storage for the photovoltaic generation system was also simulated using a time of use tariff. It was found that battery storage for the simulated system will only be economically viable when battery unit cost drops to £138/kWh. The impact of an optimised distributed energy system simulated in the Lawrence Berkeley’s Distributed Energy Resources Customer Adoption Model (DER-CAM) on distribution network constraints was investigated using a soft-linking power flow simulation procedure. It was found that voltage excursions occur mostly during peak day-types. It was found out that not all optimised distributed energy systems are feasible from the distribution network’s point of view