The German-based car hire operator Sixt has begun renting much anticipated electric vehicles this week. The release means that Sixt has gained an all important jump on its rivals in the increasingly competitive car rental market.

Customers choosing to rent with the Sixt group can now take advantage of the electric vehicles in five different German cities thanks to a pilot program that is expected to trail the vehicles for anywhere up to one year.

The vehicles have been released in Essen, where they will be available for until June 30. The fleet will then be moved to Munich, Dresden, Hamburg and finally the capital Berlin, as Sixt seeks to test the roadworthiness and customer reactions to the eco-friendly cars.

The vehicle in question is a Fiat Karabag 500 E, which is a modified, electric version Fiat’s popular 500 series. The Karabag 500 E can be rented for €59 per day while a slightly larger version, the Fiat Micro-Vett Fiorino E, which is based around the Fiorino van, can also be rented, from €79 per day.

Both models come complete with navigation equipment which is similar to GPS but shows where the range of electric charging stations are located. These are provided by the national utility operator RWE.

The timing of the release could not be better, as Sixt’s main rivals – Europcar, Hertz, and Avis – have all been making major headlines of late as the rental industry braces itself for a bumper summer. The three rental giants are all expected to release their versions of electric cars sometime in 2012.