The new fleet will include new dual fuel buses as well as the conversion and rehabilitation of existing buses to use both 30% diesel and 70% compressed natural gas (CNG).
70 green buses were displayed as the first batch of the fleet, with 190 buses planned to be operating by mid 2016.
Tau said the buses have been rebranded to demonstrate safe, reliable and quality public transport.
He added that drivers are being retrained to ensure passenger safety and improved customer service following an accident that killed two people and injured 64.
