As the penetration of intermittent renewable energy increases in European grids, the addition of more distributed flexible energy resources becomes critical. Smart electric vehicle (EV) charging approaches contribute much to this flexibility, not only by enabling fine control of EV charging rates but also by unlocking flows of energy in and out of distribution grids, buildings, and homes.

A team of researchers at the Laboratory of Electricity Markets and Power Systems of LUT University has been working on the integration of distributed resources in homes, such as batteries, renewable energy sources, and thermal storage units, with bidirectional EV charging. The aim is to optimise convenience and environmental footprint, as well as to reduce energy bills for homeowners. Smart bidirectional EV charging in residential spaces is known in expert circles as “vehicle-to-home”, or V2H.

The initiative is part of the EU project DriVe2X, “which is transforming the ways in which EV users interact with and benefit from the charging infrastructure in Europe”, explains Gonçalo Mendes, an Associate Professor at LUT University, and DriVe2X’s coordinator.

EVs are today one of the most significant components of the energy system, and their numbers are increasing very rapidly. “If we fail to properly manage the charging of these vehicles, the power system will face stability problems”, says Mendes. For this reason, smart charging is a crucial development in Europe, with the advantage of turning a potential problem into an opportunity to deliver flexibility support to the grid. “Bidirectional smart charging approaches deliver the most flexibility, but they’re also those that require the most testing due to immaturity of the technology”.

Testing solutions “Made in Europe”

In one of its pilots in Budapest, Hungary, DriVe2X is testing the integration of flexible bidirectional EV chargers with home energy management systems (HEMS). Ville Tikka, a senior electric mobility expert at LUT indicates that “the project is responsible for developing the whole chain of technologies to conduct its V2H experiments, from the chargers themselves to the control strategies to operate it in a smarter and greener way for the homes”. For this, LUT draws on close cooperation with technology partners from the UK and Hungary.

A research team led by Professor Vahid Vahidinasab at the University of Salford, UK, developed a new generation of smart charging algorithms (SCAs) that optimize EV charging and discharging by aligning household energy needs, renewable energy generation forecasts, and pricing signals. In this way, smart charging acts as an enabler for energy self-sufficiency of local communities, allowing for better integration of renewable generation, more resiliency during prolonged energy disruptions, and the creation of new value-added opportunities for EV owners.

The smart home chargers with integrated HEMS functionality are produced by General Mechatronics LLC, a Hungarian provider of engineering services and of a wide range of electronic products. The innovative unit advances existing home EV charging technology by enabling real-time monitoring and optimal control of renewable energy sources and key household loads, enhancing the energy efficiency and management capabilities of the home.

Studying smart control strategies

One of the project's innovative smart charging approaches explores residential prosumers’ tariff optimisation, where the EV battery is treated as a distributed energy resource (DER) working in tandem with the HEMS. Under this use case, homeowners can charge their EVs during periods of low-cost electricity and discharge it during high-cost periods, reducing overall energy bills. Other approaches include maximising self-consumption and energy sales from renewable sources, so to reduce emissions associated with the home energy affairs. “All of these are valuable opportunities that will in the future be available to the bulk of European consumers and that deserve further testing”, highlights Tikka.

And that’s not all. V2H schemes involving synergies between EVs, HEMS and other residential DERs – like rooftop solar and electric storage – enable households to not only manage their energy more intelligently but also to participate in demand response programmes, which in some European countries could retrieve service revenues. “The thing is that once you start managing in a smart way the flexible devices inside a home along the bidirectional EV chargers, you really see the business case shaping up”, Mendes says, “and we are developing the business models to enable it”.

Promoting open-source solutions

The implementation of the SCAs is now moving towards the real-world testing phase using Home Assistant, an open-source home automation platform adopted for its powerful and modular architecture, which is empowered by a worldwide community of users and developers. “By investing our resources in expanding the application scope of open-source solutions, we ensure maximum replicability and impact of our project’s results”, explains Mendes.

Mohammad Seyfi, who is a Ph.D. candidate at LUT University, guides us through the process: “The household’s load profile is modelled in the Home Assistant environment, the platform where the SCAs are deployed to enable intelligent scheduling and optimisation of bidirectional electric vehicle charging.” Home Assistant, an open-source platform, allows for real-time monitoring, data collection, and control of various smart home devices, forming the backbone of the HEMS. It also supports advanced functionalities such as bidirectional EV charging and the integration of custom automation strategies. “In this way, we enable optimised and automated control of energy flows in the home,” explains Seyfi. The ongoing work is focused on modelling the operation of the home energy assets and on determining the appropriate level of user input in the automation system. The team is exploring how much control and customisation could be sustainably and conveniently handled by the homeowners themselves. “We want to ensure user autonomy and maintain a sense of agency, while still capitalising on the power of automation”, Seyfi asserts. The goal is to strike a transparent balance between user preferences and smart control directives, and this is likely to become the energy decision-making model for most European homes of the future.

For now, testing is the watchword! Can we transform residential energy management by implementing home automation that considers both technical and human factors? Can we enable prosumers to be active participants in a more flexible and sustainable energy system? In a nutshell, will smart EV charging technologies and V2H deliver on its promises?

To find out the answers to these questions and many more, make sure you stay tuned for more news on the DriVe2X project.
Visit us at https://www.drive2x.eu

Article by Gonçalo Pinto Mendes