Thermo-electric generators promise higher driving range

February 02, 2017 // By Christoph Hammerschmidt
In a cooperation with Yamaha Corp, German aerospace research center DLR is developing thermos-electric systems for use in cars. The goal of the collaboration is creating systems that transform waste heat from combustion engines in road and rail vehicles into electric energy that can be fed back into the vehicle’s batteries, off-loading its electric systems and thus increasing its fuel efficiency. The technology could also be interesting for electric vehicles.

Combustion engines are known to have a rather poor energy efficiency: They utilize only about one third of the primary energy contained in the fuel; the remaining two thirds are transformed into heat and are cooled away without further use (besides heating during the cold season). Thermo-electric generators make use of this waste heat and turn them into electric energy that in turn can be utilized to run electric systems such as driver assistance systems or comfort electronics. Thus, these generators can off-load the alternator. In hybrid vehicles or electric vehicles equipped with a range extender, the energy recovered by means of a thermos-electric generator can be fed directly into the traction battery.

The scientists from Yamaha and DLR believe they can reduce a vehicle’s fuel consumption by 3 to 5 per cent through if they utilize thermo-electric generators. The goal of their project is creating a prototype that subsequently can be commercialized. Along with partners from the research community and from the industry, the DLR’s Institute for Vehicle Concepts has already developed and tested first system integrations based on thermos-electric systems. However, they found the availability of suitable thermo-electric elements very limited.