A German-Japanese research venture is developing prototype thermoelectric generator modules for on-road and rail vehicles.

Yamaha Corporation is contributing expertise in the procurement and manufacture of units made of semiconductor materials, and the German Aerospace Center (Deutsches Zentrum für Luft-und Raumfahrt; DLR) is contributing knowledge to the design and optimization of vehicle energy systems.

Prototype thermoelectric module. Source: DLRVehicular internal combustion engines use only about one-third of the potential energy in fuel for propulsion, losing the remaining two-thirds as waste heat. Thermoelectric generators use this heat and convert it into electricity, which can then be used in the vehicle for control units or convenience electronics. This reduces the load on the alternator, which would otherwise have to generate this power.

In hybrid and range-extender vehicles with internal combustion engines, the power obtained from a thermoelectric generator can be fed directly to the battery. The goal of DLR researchers is to reduce fuel consumption by 3-5% percent using thermoelectric generators.

As industrially-produced thermoelectric modules have been available to a very limited extent, the engineers have had to resort to modules that were not specifically designed for vehicular application. However, DLR has recently developed systems based on thermoelectric generators and successfully tested them in a car.

The first research demonstrators are currently being tested in the laboratory to further optimize details regarding vehicular suitability and efficiency.