- Press Release
gridX and E.ON develop optimised charging and Vehicle2Home solution
As part of the "xHouse" project, the two partners are developing a dynamic charging solution in private households and are testing the electric vehicle as a flexible energy storage device.

gridX and E.ON are equipping the so-called "xHouse" with an intelligent energy management system and are also testing bidirectional charging of electric vehicles, among other things. Here, the electric vehicle is used as a flexible electricity storage device which exchanges energy with the home as required.

One challenge of the energy turnaround and decentralisation is the lack of a possibility to store large amounts of electricity. On sunny days, for example, a photovoltaic system generates much more energy than is needed. The surplus energy cannot always be drawn off and cannot be stored sufficiently. At night or in bad weather, when photovoltaic systems do not generate electricity, this can lead to energy shortages. The electric vehicle can optimally counteract this. It provides the required energy by using it as a flexible electricity storage device.

E.ON and gridX are testing and developing energy management and bidirectional charging with the Nissan Leaf in the "xHouse". The battery of the electric car can be charged via the charging station at home, at work or in public and can also return energy to the house as a decentralised storage medium. The residents of the "xHouse" have a photovoltaic system. Here, the electric vehicle thus serves as an intermediate storage for the electricity generated by the house. If the sun does not shine sufficiently, the vehicle releases the stored electricity back to the house when there are bottlenecks.

The "xHouse" is a real use case from E.ON and gridX. There, the interaction of photovoltaic, storage and bidirectional charging station is tested. The grid connection point of the house is 14.5 kW. The Nissan Leaf, which is used in the "xHouse", operates with a DC charging point, which enables an output of 10 kW, and three stationary battery storage units, each with a capacity of 9 kWh. The electric vehicle itself has a battery capacity of 40 kWh. The photovoltaic system, which supplies the house with self-generated electricity, has a total size of 5.6 kWp. In addition, the "xHouse" is equipped with Smart Building technology, which enables the control of light and heating. The various components from different manufacturers are intelligently linked with the help of gridBox, the control component within the energy management system. This is able to read out the various protocols and intelligently controls the power consumption in the house.

"Thanks to the possibility of bidirectional charging, I can use my self-generated electricity more efficiently. As a homeowner, I don't like it when I have to feed my solar electricity into the grid and the PV system is throttled down to 70% output. It is nice to know that a large proportion of the energy can be temporarily stored in the electric car. Bidirectional charging is a real gain! It supports both the energy demand in the house and mobility",

says Karsten Sund, resident of "xHouse" and long-term user.

The Vehicle2Home solution is an important step into the future of decentralised and digital energy management.

"To make the energy turnaround a reality, intelligent and future-oriented solutions are needed to make electricity from renewable energies efficiently usable. This also includes the possibility of storing energy flexibly and decentrally. The electric vehicle offers great potential for this and provides real potential for residents in the 'xHouse'",

says Dr. Lioudmila Simon, Head Innovation Networked Mobility at E.ON Group Innovation.

Thanks to the intelligent energy management in the "xHouse", the degree of self-sufficiency of the house could be significantly increased, which means that less electricity had to be fed into the grid and that battery charging was largely based on self-generated electricity. Mobility continues to be the focus of attention. The intelligent energy management system ensures that the electric vehicle does not deliver all of the electricity to the house, thus providing sufficient range for electric journeys at all times. The residents are not restricted in their mobility. The energy management system automatically optimises energy use, making it extremely easy for residents and users to operate. In a user-friendly and clearly arranged dashboard, users can monitor energy flows at any time. Bidirectional charge control is also carried out via the dashboard. The user can decide when and to what extent he wants to allow charging and discharging of the electric vehicle. The state of charge is transparent and the minimum range of the vehicle can be defined individually.

"Bidirectional charging brings great advantages for users and the energy industry. On the one hand, the solution contributes to stabilising the grid and bringing more supply security to a decentralised energy world. On the other hand it allows the user to implement individual mobility wishes and save money",

says Andreas Booke, Founder and Managing Director of gridX.

About gridX

Climate change is the biggest challenge of our times but today's power grid is not built for the uncertainty and decentral nature of renewable energies. gridX builds the digital infrastructure to enable the energy transition. Therefore, gridX develops XENON the platform to connect all distributed energy resources. gridX customers can develop their own energy applications on top of XENON or opt for ready-made solutions.