SunCar by ETH Zürich: Full performance, clean energy
A car that is able to drive over long distances without burning fossil fuels, powered only be renewable energies: This is no vision of a distant future, but a current project being undertaken at ETH Zurich. The rollout of the «SunCar» was held on 31 May 2011. This was made possible by a hard-working team of students – and the support of HUBER+SUHNER.
The SunCar is based on a Lotus Evora with completely newly developed and converted inner workings. The drive is provided by two electric motors, powered by a highperformance battery. This is supported by a photovoltaic system on the vehicle’s outer skin, a solar charging station and a range extender in the shape of a single-cylinder biofuel combustion engine. HUBER+SUHNER supplied all the cables for the vehicle and the solar charging station as well as providing the services of a trainee electrician for their installation and donating 25,000 Swiss francs.
Simon Pfister wiring the SunCar
The two 250 kW electric motors, the batteries and other heavy components were positioned in the vehicle such as to ensure an even weight distribution. By means of a skilful redesign of certain body parts, more space was obtained for the additional components like the batteries and range extender. The chargers, range extender, batteries and converters for the motors had to interact smoothly in order to exploit the full energy efficiency. Furthermore, a software was developed for the dashboard display, which provides the driver with key data such as the charge state of the batteries, current range and savings achieved through energy recovery.
Simon Pfister, a trainee electrician in his third year at HUBER+SUHNER in Herisau took part in the project. The idea of involving a practician in addition to the 50 students from the ETH and polytechnics stemmed from the ETH itself. Simon Pfister installed the orange RADOX cables donated by HUBER+SUHNER for the high voltage vehicle electrical system with the greatest of care. SunCar Project Manager Professor David Dyntar praised his efforts, «Simon had to work very accurately. After all, these are 400-volt lines. Incorrect installation of the connections could result in dangerous sparks. With his practical experience and know-how, he proved a valuable help.»
RADOX cables for solar charging station
The power for the electric motors is obtained exclusively from solar energy. «After all, the sun provides us with 10,000 times more energy than we actually need – and it’s free of charge!» said David Dyntar. Thanks to a thin, maximum- efficiency photovoltaic coating applied to the body, the vehicle itself also produces electricity. This coating, which supplies the energy for the battery cooling system when the vehicle is stationary, has to withstand the exterior influences that arise during everyday driving. The challenge was to optimally utilise the surface on the vehicle, without sacrificing functionality. Power needed for the vehicle is additionally provided by a photovoltaic system which was permanently installed on the roof of a house. This solar charging station is also equipped with RADOX cables and connectors donated by HUBER+SUHNER.
The limited range is one of the principle drawbacks of today’s electric vehicles. For this reason, a range extender was used in the SunCar. This consists of a bio-ethanol combustion engine that generates electric power by means of a generator. This is used to charge the batteries during driving, or to power the electric motors directly. Here also, the fuel is obtained exclusively from renewable energies, for example wood. With a range of 250 km, the vehicle can be used fully electrically during short-range driving. Thanks to the range extender, distances up to 1,000 km are possible.
Childhood dream comes true
«Even as a child, I dreamed of building a fully-fledged car that could be operated without burning petrol or diesel,» says David Dyntar with enthusiasm. «A complete system that operates solely with renewable energies. With the SunCar, we have reached a decisive milestone.» After the rollout of the SunCar at the ETH in Zurich, the vehicle will now go on view in a variety of exhibitions on the subject of electric mobility. HUBER+SUHNER is proud to have fulfilled his dreams through his involvement in this project and to have jointly made a decisive step into the new era of electric mobility with the ETH.