Audi currently has a range of models that carry a lower case ‘e’ as part of their title to denote their fuel-efficiency prowess, but a new report has revealed the carmaker is planning a new family of eco-friendly vehicles, codenamed E1 to E5 and spanning everything from minicars to performance models. Unlike the existing e designated cars, which were based on standard models already in production, the new E range will consist of unique standalone vehicles.

According to CAR, the first vehicle of the new E range has been given the green light. The car is a new minicar dubbed the E1. It will be based around Volkswagen Group’s new NSF platform, the same architecture that will underpin the production version of the 2007 up! concept, but it will feature its own unique body. Powertrain options will include both petrol and turbodiesel units and eventually a battery-powered electric motor.

If successful, the E1 will be followed by the E2. This will essentially be Audi’s version of the 2009 VW BlueSport concept from last week’s Detroit Auto Show. It will be a mid-engined roadster designed to rival the likes of the Lotus Elise and Porsche Boxster. Once again, compact petrol and turbodiesel engines are the likely option, however, an-electric version could also be offered.

For the E3, sources indicate that Audi will release a compact hatch built on an aluminum chassis that will be shared with the next-generation A3. The new E3 will be the spiritual successor to the A2 from the 1990s and will share many of its components with the NSF-based cars.

Following the E3 will be a sporty hatch based around 2006’s Roadjet concept car. This vehicle will be called the E4 and will essentially be a larger and more expensive version of the E3, which means more powerful engine options will be available, including the possibility of a hybrid powertrain.

Finally there will the E5, a new eco-friendly sports car that is expected to arrive around 2014. Information about this model is scarce but insiders suggest the car will be compact and feature the latest in lightweight construction techniques. It is also expected to feature a performance S variant to be called the E5S.