Siemens hybrid tramway system with cooling made by technotrans / High-performance temperature control system defies the heat / Certificates confirm the efficiency of the system

As of 2016, tramways made by Siemens and equipped with cooling systems made by technotrans AG from Sassenberg will be in use in Qatar. The cooling systems will ensure the optimum cooling of the energy storage systems even under the extreme conditions in the desert state. The Avenio trams use capacitors as well as traction batteries so that they are catenary-free.

"We need a powerful, lightweight, and reliable cooling system for the capacitors and batteries," says Jochen Steinbauer, project manager at Siemens Mobility in the Turnkey Projects & Electrification division. For the equipment of the hybrid tramways in Qatar's capital Doha, Siemens opts for cooling systems made by technotrans. With its lightweight cooling solution, technotrans remained well below the specified maximum weight. In addition, the experts from Sassenberg proactively qualified all of the cooling systems for their area of application beyond the obligatory certifications.

Avenio is completely catenary-free on its network with a total of 11.5 kilometres. This is made possible by a hybrid energy storage system that ensures an environmentally friendly and efficient mode of transport by way of capacitors and traction batteries. The batteries, cooling system, and capacitors are integrated in the roof of the trams. During deceleration and acceleration, heat is produced – in addition to the already very high temperatures in Qatar. Consequently, the energy storage systems require efficient cooling for trouble-free operation.

A truly reliable partner on an equal footing
One explanation of the high performance level of the technotrans systems is the use of water instead of air for the cooling process. The design of the systems for the capacitors and batteries ensures that the energy storage systems will not heat up to more than 20°C even at peak ambient temperatures in Qatar.

For Siemens, the order from Qatar is a classic turnkey project enabling the company to establish a new system on the market. This is why Siemens regularly reviewed the component suppliers by way of audits during the development phase. In addition, the company also pointed out problems, so-called findings. "It was really rather unusual, but there were absolutely no findings concerning the cooling system," says Jochen Steinbauer. "As a result, technotrans quickly gained an excellent reputation at Siemens."

Thanks to the capacitor-battery-combination, Avenio trams require 30 per cent less energy than comparable, catenary-supplied models on an annual average. The special tramway system will be built in Vienna until the end of 2015. Following their completion, the trams will then be delivered to Qatar. Regular operations in Qatar will commence in 2016.