PHEV able to run 50 miles on a pure electric charge. After that, you can extend your trip to more than 620 miles with the Karma's gas or diesel engine, which will reportedly get close to 100 miles to the gallon
http://www.thecarconnection.com/Vehicle_Reviews/Hybrid_Cars_Electric_Cars_Diesels/2010_Fisker_Karma_Preview.S274.A13828.html
http://www.thecarconnection.com/Vehicle_Reviews/Hybrid_Cars_Electric_Cars_Diesels/2010_Fisker_Karma_Preview.S274.A13828.html