Munich  - The Toyota Prius hybrid continues to lead the Eco-Test rankings conducted annually by Germany's automobile association (ADAC) which measured fuel consumption and carbon dioxide emissions in a special test.

None of the 800 cars tested achieved the maximum number of five stars. The ADAC says its test is more realistic than the fuel consumption tests conducted under laboratory conditions by the car makers. The Eco-Test takes the cars on motorways, stop-and-go city traffic while the air conditioning systems run.

Although the Prius still has four stars, its main competitors in the medium-sized car segment were catching up, notably the Skoda Superb 2.0 TDI Elegance and the VW Passat BlueMotion (diesel), the ADAC said.

In the upmarket luxury segment, the Audi A8 2.8 FSI e-multitronic headed the list while in the small car segment the Opel Corsa 1.3 CDTI ecoFlex and the VW Polo BlueMotion (diesel) were most efficient. In the microcar sector the Fiat Panda 1.2 8V running on natural gas was the cleanest in its class. (dpa)