Global awareness on the effects of carbon emissions are on the rise. Globally, transport is responsible for over a fifth of the total CO2 emitted. As such, global research focus has been shifted towards decarbonizing current energy systems and transportation. Nonetheless, transition from conventional vehicles to low carbon emission ones is moving slower than anticipated, despite the fact that its importance has been highlighted in all relevant policy documents. It is therefore evident that solutions for changing transportation habits and preferences of end-users require an integrated approach, especially in designing models for end-users and encouraging them to make a quicker transition to electrified transport, as defined by the relevant regulatory goals. In essence, this means being aware of technical, economic and social constraints when creating models to make electrification of the transport an alternative new flexibility source. At present, existing models designed to reap the benefits of electric vehicles’ flexibility in literature almost exclusively identify charging stations as active players exploiting this flexibility. Such stations are seen as static loads able to provide flexibility only when electric vehicles are connected to them. This standpoint, however, suffers from two major issues. First, the charging stations need to anticipate important parameters of the incoming vehicles, e.g. time of arrival/departure, state-of-energy at arrival/departure. Second, it interacts with vehicles only when connected to a specific charging station, thus overlooking the arbitrage opportunities when they are connected to other stations. This conventional way of addressing the electric vehicles is referred to as charging station-based e-mobility system.
In light of this, there is need that a novel approach be developed that circumvents these shortfalls. On this account, researchers from the Faculty of Electrical Engineering and Computing, University of Zagreb, Croatia: Dr. Ivan Pavić, Dr. Hrvoje Pandžić and Dr. Tomislav Capuder developed a new concept of using the EV flexibility more efficiently in a world with a multitude of new data streams relying on information-communication technologies in vehicles and without any loss of comfort for EV drivers. Their wok is currently published in the research journal, Applied Energy.
Ideally, the usual understanding of smart e-mobility is that Charging Stations (CSs) use EVs to provide flexibility to the power system, in their approach however, they challenged this generally accepted norm and reversed the roles in that they identified EVs themselves as smart players that provide flexibility and the charging stations as merely an enabling infrastructure. The researchers argued that the state-of-the-art literature, research projects and e-mobility sector currently conceive the smart e-mobility in a way which leads to an underutilization of the EV flexibility and to insufficient financial returns.
The authors contributed to the body of knowledge in the field of EV aggregation by introducing a design and formulation of a novel EVA model tracking the EVs during their trips, thus capturing all relevant trip and battery information. Moreover, they introduced a systematic and rigorous comparative assessment of the CS-based and EV-based models. Remarkably, the researchers were also able to demonstrate that aggregate EV models without relevant features, such as power levels and grid tariffs, result in incorrect conclusions regarding the cost of EV charging.
In summary, the study demonstrated on a small scale experiment the shortcomings of the Charging station-based concept, which is predominantly used by global research community. Contrary to the aforementioned conventional concept which aggregates the charging stations, the proposed electric vehicle-based concept aggregated vehicles themselves. This was reported to enabled optimal charging schedule for each electric vehicle, regardless of where it was charged. In a statement to Advances in Engineering, Dr. Tomislav Capuder said their proposed system yielded better results for vehicle owners. He further mentioned that if integrated into existing systems, the proposed EV battery aggregator approach could create substantial market advantage and result in higher profits.
Ivan Pavić, Hrvoje Pandžić, Tomislav Capuder. Electric vehicle based smart e-mobility system – Definition and comparison to the existing concept. Applied Energy, volume 272 (2020) 115153.