Electric mobility meets renewable energy

The results of the research project “iZEUS – intelligent Zero Emission Urban System” were presented at an event at EnBW City on 24 June 2014. Over around two and a half years, an inter-disciplinary team from the worlds of business and science have been integrating the Smart Grid and Smart Traffic concepts. The project underpins the federal government’s target of bringing one million electric cars onto the streets of Germany by 2020. It received backing from the Federal Ministry of Economic Affairs and Energy of around €12.5 million.

The concept behind iZEUS goes well beyond previous research projects by linking together transport and energy systems as well as roaming and innovative billing concepts. It plans to optimise the integration of renewable energy sources and to implement stable decentralised energy and charging management.

A test fleet of around 60 electric cars – comprising smart fortwo electric drive, Mercedes-Benz Vito E-CELL, Opel Ampera and Toyota Opel Prius Plug-In Hybrid vehicles – were fitted with a new navigation system for this purpose. The PTV Group, TWT GmbH and the Karlsruhe Institute for Technology (KIT) had developed it especially for the field experiment: When calculating the routing, the navigation takes into account the vehicle’s range and shows charging stations on the route.

“Electric mobility in everyday life – I have been delighted to be able to contribute to the iZEUS project. The records of the routes with the tablet provided have been very enjoyable and I hope that electric mobility will quickly grow in importance” (iZEUS customer, Ulrich Lauterbach from Völmle & Rickert GmbH).

The Fraunhofer Institute for System and Innovation Research ISI and for Solar Energy Systems ISE have worked in close collaboration to research innovative network integration concepts for electric vehicles and renewable energies. To this end, a bi-directional charger with a built-in function for the real-time analysis of distribution networks has been developed and tested. The system’s very high efficiency reduces the users’ charging costs and moreover significantly contributes to preventing electric mobility emissions by conserving energy. The concept of using the vehicle to monitor the network indicates a potential method for how in the future smart charging could be assisted by renewable energy, without expensive and difficult-to-finance charging infrastructure. Further key issues were the analysis of the fleet test results and the acceptance of the applications tested in the trial.

The bi-directional charge management was tested with an Opel Meriva electric car at KIT’s Energy Smart Home Lab. In several housing situations, energy management could be optimised at the household level by integrating the vehicle battery with external network factors.

SAP and EnBW took care of the energy management of the electric car fleet: In order to calculate the load transfer potential automatically and then be able to pass this information on to the fleet energy management, the project partners installed smart charging options at various locations. Daimler AG drew up standards for controlled charging in vehicles to take account of fluctuations in the energy supply through the intelligent adjustment of the charging intensity (ISO 15118).

IT specialists ads-tec provided a fixed lithium-ion storage battery, which was tested in Esslingen on the medium-voltage grid of EnBW subsidiary, Netze BW. These storage batteries are due in the future to integrate renewable energies into the power system, independently regulate the operating reserve, voltage and load on the network and act as virtual storage for numerous users.

For the fleet test, EnBW, the consortium leader for the research project, offered its entire regional charging system with over 600 charging stations throughout Baden-Württemberg. In addition, the first nationwide rechargeable prepaid card for electricity was developed.

“With iZEUS, electric mobility has reached the customer“, said Uwe Fritz, head of B2B sales & new products at EnBW, echoing the consortium’s view. “The pilot project has launched partnerships with charging systems and consequently spurred on the expansion of infrastructure up and down the country. It has brought vehicle buyers closer to tailor-made navigation and non-discriminatory access systems. In short, iZEUS has laid down important and correct cues about the feasibility of electric mobility.“

“iZEUS has shown that electric mobility can work in everyday urban environments“, says Dr. Alexander Tettenborn, head of the Department for the Development of Convergent ICT at the Federal Ministry of Economic Affairs and Energy. “The interests of electric car users and energy producers will therefore be taken into account in equal measure. With a whole array of solutions for fleet and energy management, mobility and billing services as well as network-protecting charging strategies, iZEUS moves electric mobility a huge step forward. At the same time, the project makes an important contribution towards bringing about a change in energy policy.”

The process on which the project is based was supported with funds from the Federal Ministry of Economic Affairs and Energy.