ETS conducted a fuel systems study beginning in the spring of 2007 to compare the performance of several different types of hybrid drive systems as well as a modern electric trolley propulsion system. To enable this comparison, six hybrid buses were purchased from two manufacturers and one electric trolley bus was leased from Translink in Vancouver. These buses were as follows:
#6000: 2007 New Flyer E40LFR (Translink #2242)
#6001, 6002: 2007 New Flyer DE40LFR with Allison EP40 parallel hybrid drive
#6003, 6004: 2007 New Flyer DE40LFR with ISE ThunderVolt serial hybrid drive
#6005, 6006: 2006 Orion VII HEV with BAE Systems serial hybrid drive