( dpa )- Buyers of the super sports cars are mostly looking at speed and fun but the environmental debate has also had its effects on this niche market with several manufacturers now offering cars that promise both a clear "green" conscience and high performance.
Several sports car makers presented their ideas on how to combine the two worlds at the recent Detroit Motor Show.
Audi showed a concept study of a super sports car fitted with a diesel engine based on the race car that won the 24 hour Le Mans race twice.
The Audi R8 V12 TDI concept generates a huge 500 hp and 1,000 Newton- metres of torque, putting to rest any remaining doubts that a diesel engine is a lame duck.
With a top speed of more than 300 kilometres an hour and acceleration from zero to 100 km/h in just 4.2 seconds, the car still falls in the category of a "clean diesel" with a fuel consumption of a medium sized saloon of less than 10 litres per 100 kilometres , according to engine developer Michael Dick.
Mitsubishi showed the Concept-RA to indicate what the next generation of the sports coupe Eclipse could look like. The concept is fitted with a "clean diesel" with an output of 150 kW/204 hp.
Ferrari are also betting on sports car fans wanting a car with a "green" touch. It has developed a V8 F430 for use with E85 ethanol fuel. The Italian manufacturer says power has been boosted by 7 kW/10 hp to 368 kW/500 hp while carbon dioxide emissions are down 5 per cent compared to the petrol-only version.
Mazda in turn orientates itself on a revival of the Wankel rotary engine with its futuristic Furai study. The 331 kW/450 hp engine is powered by pure ethanol produced from plant residue, maize or corn.
"This reduces the dependency on oil and brings emission figures of the Furai to a level never seen before in a vehicle with such a performance," says Mazda's Germany spokesman Jochen Muenzinger .
While the three concepts are officially still described as studies, the most unusual concept presented in Detroit has scheduled production for the second half of 2009.
The former BMW and Aston Martin designer Henrik Fisker has built the sports limousine, Karma, powered by an electric motor fitted to the rear axle that catapults the vehicle to 100 km/h in six seconds. The top speed is over 200 km/h.
Power comes from a lithium-ion battery which provides a range of 80 kilometres . For longer trips the Karma switches to a four-cylinder petrol engine that reloads the battery through a generator. In addition there is the option of a solar roof that supplies the air conditioner with energy during parking and stores excess energy in the battery.
But it is not only the technology that excites. The manufacturers are aiming to sell the car for about 54,000 euros (80,000 dollars) which makes it a real bargain in this sports car category.