The European Union's Vision 20-20-20 for emission reduction combined with the proliferation of shale gas in North America is renewing interest in alternate and cleaner powertrain technologies. Although fully electric vehicles are considered the definitive future of automobile powertrains, existing limitations in battery range and cost competitiveness have inhibited their mass adoption in the commercial vehicle industry. The recent product announcements and launches by traditional truck and bus OEMs such as Daimler AG and Volvo Group alongside start-ups such as Tesla, Nikola, and Proterra is indicative of expected widespread adoption of hybrid-electric technology in North America and Europe.