The diffusion of sustainable and innovative means of transport plays a fundamental role in the energy transition and national environmental policies. However, a rapid and significant diffusion of electric vehicles can be a challenge for the electricity system. It is therefore of particular interest to develop technologies that allow electric vehicles to also become an opportunity for the electricity grid. The activity carried out aims to analyse and experiment the use of electric vehicles as a useful flexibility tool for the grid.

The research activity presented in this report aimed to evaluate the technical-economic potential of services offered by an aggregate of electric vehicles connected through V2G columns and to carry out the first experiments on the V2G columns installed in the Distributed Generation Test Facility.

In the first part of the paper, the potential profitability of services offered by an aggregate of electric vehicles was assessed, considering as a case study the charging of employees’ cars at the workplace and considering real data of RSE employees. With the hypothesis of providing services as expected for ‘UVAMs’ (Mixed Enabled Virtual Units), an optimisation programme was developed that allows to plan the charging profiles of electric vehicles for the following day, with the aim of charging EVs and providing services to the grid. The model created also allowed us to carry out an economic analysis on a one year time horizon and also considering aggregate with lower power (200 kW) than that expected for UVAMs (1 MW). It was verified that, when costs are charged for the energy withdrawn from the grid, Smart Charging (V1G) is the only option that would bring an economic advantage, corresponding to a saving of 68% compared to charging the vehicle alone. Conversely, when dispatching charges are applied to the portion of energy withdrawn net of that supplied for grid services, the V2G case is also convenient, with savings of up to 62% even considering battery wear.

The second part of the document presents the ICT integration of the Enel X bidirectional columns in the RSE DER-TF plant management software and the preliminary tests carried out on a Nissan Leaf electric vehicle. It was verified that it is possible to use approximately 36 kWh out of the 40 kWh available, to provide services to the grid. The vehicle’s battery is discharged and recharged with a round-trip efficiency evaluated on the AC side of over 82%. The charging and discharging phases do not present significant power limitations, except for charge states close to 90% and it is therefore possible to use these electric vehicles, connected to the V2G columns, to provide services to the grid with wide flexibility in power and energy.