Related by context. Frequent words. (Click for all words.) 54 Aptera 51 X Prize 45 Volt 45 Automotive X PRIZE 45 Fisker 44 DARPA 44 electric powertrain 43 hybrid electric 43 electric propulsion 42 hydrogen powered 42 Brammo 42 Lotus Engineering 42 hybrid powertrain 42 Tesla 42 A#Systems 42 ultracapacitors 42 diesel powered 42 Chevy Volt 42 HEVs 42 HondaJet 42 Fisker Automotive 42 zero emission 42 Orbital Sciences Corp. 41 Tesla Roadster 41 lithium ion battery 41 rotary engine 41 CTS V 41 hydrogen fuel 41 Skybus 41 powertrain 41 electric hybrid 41 hybrid Prius 41 powertrains 41 Burt Rutan 41 Ansari X 41 Vectrix 41 lithium ion 41 Camry Hybrid 40 PHEV 40 Ford Transit Connect 40 Lotus Elise 40 Darpa 40 Chevrolet Volt plug 40 ARPA E 40 EnerDel 40 PHEVs 40 proton exchange 40 Terrafugia 40 Escape Hybrid 40 diesels 40 Fusion Hybrid 39 Autocar 39 Scaled Composites 39 Li ion 39 Chevrolet Volt 39 Smart Fortwo 39 Cruze 39 electrically driven 39 CR Z 39 Tata Nano 39 hydrogen 39 alternative fuels 39 midsize sedan 39 Honda CR Z 39 Fuel Cell 39 ZR1 38 cellulosic biofuels 38 nonpolluting 38 Ford Escape Hybrid 38 VLJ 38 Fisker Karma 38 drivetrains 38 UQM 38 silicon photonics 38 Roadster 38 lithium ion batteries 38 XCOR 38 combustion engines 37 Continental GT 37 Audi A1 37 hybrids 37 biobutanol 37 MTI Micro 37 Jetta TDI 37 combustion engine 37 electric hybrids 37 SOFC 37 Toyota Prius 37 diesel engine 37 Volvo 37 Carbon Motors 37 V6 engines 37 Li ion batteries 37 hybrid propulsion 37 Chevrolet Cruze 37 FCX Clarity 37 drivetrain 37 cellulosic 37 propulsion 37 supercar 36 Nanosolar