In 2008, Alexander Dennis unveiled the hybrid-electric powered version of Trident 2 (the Enviro400H) using BAE Systems's HybriDrive series drive system with Cummins ISBe 4-cylinder engine fitted for power generation. Also in the same year, Alexander Dennis unveiled the further developed version of Trident 2 for the "New Generation" Enviro400, with the engine being moved to the left side and the radiator being moved to the right side of the engine compartment. It could be fitted with Cummins ISBe Euro V/EEV or MAN D0836LOH engine, coupled to Voith DIWA or ZF EcoLife gearbox. In 2009, Alexander Dennis developed the Hong Kong version of the Trident 2 (Enviro400). Based on the further developed version unveiled in 2008, it has a longer rear overhang and could be fitted with Cummins ISLe Euro V engine.