Paul Codani

Distribution grid services and flexibility provision by electric vehicles: A review of options

Due to the increasing penetration of distributed generation and new high-power consumption loads - such as electric vehicles (EVs) - distribution system operators (DSO) are facing new grid security challenges. DSOs have historically dealt with such issues by making investments in grid reinforcement. However, an alternative solution, enabled by the expected roll-out of smart meters and high penetration of flexible loads, would be the increased use of flexibility services. Flexible loads, with EVs at their forefront, can modulate their consumption or even inject power back to the grid depending on current grid conditions. In return, flexibility provision should be remunerated accordingly. In this paper, the authors are interested in making an accurate description of the flexibility services at the distribution level which could be provided by EVs as well as their requirements, e.g. location, activation time and duration. Market design recommendations for enhancing the provision of DSO grid services by EVs are derived from the conducted analysis.

Aggregation of demand side flexibility in a smart grid: A review for European market design

The increased share of renewable generation and the integration of Distributed Generation (DG) require more electricity system flexibility. One way to increase this flexibility is to use the potentials of demand response (DR). In order to activate the full range of customers in DR, a new market intermediary actor is needed to aggregate the resources in an adequate technical and economical format. These actors, so called “aggregators”, can act as flexibility providers to support security of supply considering network, generation and consumers constraints. However, despite their technical and economical utility, aggregators are not self-emerging in many European countries. Consequently, this paper aims at identifying the main barriers accounting for this lack of aggregators in Europe. Eventually this paper provides a policy review for European market designs that support aggregation.

Participation of an Electric Vehicle Fleet to Primary Frequency Control in France

Using electric vehicles (EV) as distributed storage units could be a solution to take advantage of the good availability of EVs and reduce their total cost of ownership. The scientific literature features frequency control as one of the most profitable electric markets for EV fleets. This paper presents an economic evaluation of the expected remuneration for a fleet of EVs participating in primary frequency control in France in 2020. First, the modelling of a French EV fleet is addressed. Simulations of the participation of this fleet in the French primary frequency control market are then performed. Two regulation strategies are considered: in the first one, only unidirectional power exchanges are allowed between EVs and the grid, while in the second one bidirectional exchanges are allowed. Results show that the expected remuneration is highly dependent on the ability to charge at work, the power level of the charging stations, and the bidirectional capabilities of the cars.

Diversity of transmission system operators for Grid Integrated Vehicles

A modular framework is used to analyze how Grid Integrated Vehicles (GIVs), i.e. bi-directional plug-in electric vehicles that are able to modulate their charging rate and have bi-directional capabilities, could be managed efficiently to deliver valuable grid services for transmission operators and conversely, how these new services could be set aside by the design of the current rules in some regions. Based on a detailed analysis of the rules implemented by some representative TSOs, we discern two modules that gather the essential rules for GIV development: the rules towards aggregation of EVs, and the rules defining the payment scheme of the services provided by GIVs. We deduce an optimal combination among these rules that could define the ideal organization for GIVs. At last, we confront this ideal TSO organization with ENTSOE guidelines.

Transformer operating conditions under introduction of PV and EVs in an eco-district

An analysis of the operating conditions of a power transformer with the introduction of photovoltaic (PV) panels and Electric Vehicles (EV) in an eco-district is conducted. The study focuses on: (a) determining the optimal transformer sizing when there is neither PV nor EV; and (b) characterizing the overloading periods of the transformer induced by the penetration of PV sources and EVs in the district. We compare two EV integration strategies: they are either considered as unmanaged loads, or controlled by an Energy Management System (EMS) with Vehicle-to-Grid (V2G) capabilities. Transformer operating curves and rated power are deduced from technical standards supplied by Schneider Electric. The results show that EVs and PV introduction has a substantial impact on overloading periods. However, the latters are seriously mitigated both in terms of energy flows and peak power with the implementation of the EMS.

Coupling local renewable energy production with electric vehicle charging: a survey of the French case

The share of renewable energy sources (RES) production in energy mixes, especially the ones of PV panels and wind farms, has been continuously increasing during the last few years. Similarly, a strong development of battery electric vehicles (EV) is expected within the next years. However, these two new innovations could trigger local security issues on electrical grids. One way to mitigate these problems could be to combine the charging periods of the EVs with the local RES production. This paper aims at analysing the possibility to implement this kind of smart charging strategy in France by 2020, taking into account the wide diversity of local energy mixes in France and their seasonal dependencies. The results show the achievable green charging ratio for the EV fleet per season and per region, with and without a smart charging strategy.