Research Project Shows How Car Sharing Vehicles Can Contribute to the Energy Transition

An innovation project by the University of Applied Sciences and Arts Northwestern Switzerland FHNW and the OST - Eastern Switzerland University of Applied Sciences demonstrates for the first time how car sharing fleets can contribute as flexible energy storage systems to grid stability. Together with the energy suppliers AEM, ewz, and Primeo Energie as well as the Mobility Cooperative, it was investigated how bidirectional charging can be technically and economically integrated into existing power grids in a meaningful way.

The conclusion: Bidirectionally charging electric cars are a practical and worthwhile component for the energy transition - both for grid operators and for fleet operators.

**From Car to Active Grid Participant**

The core question of the project was: Can electric vehicles not only draw power from the grid, but also feed it back in a targeted manner - thus relieving the power grid? The answer is yes - and not just in theory.

In several real-life field trials, Mobility vehicles were controlled so that they postponed their charging processes at certain times to specifically feed power back into the local distribution network. Result: In up to 60% of cases, network loads could be successfully reduced. Particularly during times of high demand or high PV surplus, flexible control proves to be a valuable lever.

**Intelligent Forecasting with Machine Learning**

Intelligent forecasting models predict when and for how long a vehicle is available - based on millions of real booking data from the car-sharing system. Additionally, the states of charge of the vehicle batteries were analyzed to determine how much energy can actually be stored or fed back.

Per vehicle, around 9 to 12 kWh of usable flexibility was available on average - enough to buffer significant network loads or store PV power sensibly with multiple vehicles.

**Easy Integration into the Power Grid Possible**

A particularly practical success of the project is the developed product model for marketing charging flexibility: It can be easily integrated into existing systems of distribution network operators, is standardizable throughout Switzerland, and focuses on two applications:

- 'Charging during power surplus' (for example, during high PV generation) - 'Feeding back during peak network loads'

To activate the flexible power, distribution network operators can use different types of controllers - from existing ripple control systems to modern load control systems.

The model provides payment both for providing and for the actual use of flexibility and works in a quarter-hourly grid - adapted to the network needs. This marks a significant step towards the market-based integration of e-mobility and power supply.

**Added Value for All: Environment, Grid Operators, and Users**

The project clearly shows: Decentralized e-vehicles are more than just means of transport. They are mobile, controllable energy storage systems - and thus a key to the successful sector coupling of mobility and energy.

For grid operators, this means lower costs due to peak load reduction and grid stabilization. For society, it means progress towards a climate-friendly, decentralized energy landscape. And for car-sharing providers like Mobility, it opens up new business models in the field of grid services.

**Contact and Further Information**

University of Applied Sciences and Arts Northwestern Switzerland FHNW
School of Engineering and Environment
Prof. Dr. Martin Geidl
Head of Institute for Electrical Energy Technology
Klosterzelgstrasse 2
5210 Windisch
T +41 56 202 77 03
martin.geidl@fhnw.ch

Further information at www.fhnw.ch

**The School of Engineering and Environment FHNW**

The School of Engineering and Environment of the University of Applied Sciences and Arts Northwestern Switzerland FHNW offers a wide, practice-oriented range of studies in engineering and optometry. With the addition of the environmental sector, it focuses increasingly on sustainable technologies and solutions for the challenges of our time. It conducts application-oriented research and development at its locations in Brugg-Windisch, Muttenz, and Olten, together with partners from industry and business.

www.fhnw.ch/htu

University of Applied Sciences and Arts Northwestern Switzerland FHNW
Dominik Lehmann
Head of Communication FHNW
Bahnhofstrasse 6
5210 Windisch
T +41 56 202 77 28
dominik.lehmann@fhnw.ch