Two electric buses and one hybrid bus will hit Canberra roads next month, after the ACT government signed a $900,000 contract with Carbridge and Volvo.
The 12-month trial will look at how the buses cope with the demands of the Canberra network and will guide future decisions on the replacement of ACTION's diesel buses, Transport Minister Meegan Fitzharris said.
"Recent improvements in battery technology mean that electric buses are becoming more economical and operationally viable, coupled with obvious environmental benefits," Ms Fitzharris said.
"If electric or electric-hybrid buses are found suitable following the trial, Transport Canberra will consider alternative fuel buses as part of the broader fleet replacement options."
Carbridge will supply the electric buses, while Volvo built the hybrid.
The trial was supposed to begin in February, but was delayed after the contract with Avass Bus Manufacturing fell through.
Ms Fitzharris said at the time the government terminated the contract because it became clear Avass would not deliver the three electric buses by the deadline.
However Avass chief executive Allen Saylav said the buses would have been ready had the government granted them the three-month extension it requested.
Avass general counsel Matthew Sandman said the company had needed extra time for testing.
The new request for tenders opened the door for hybrid buses, which the ACT government's executive director of public transport operations, David Matthews, said was in response to the products on the market.
"We've got both under this trial and it gives us ability to look at a range of different technologies and make an assessment for us for the right mix of fuels going forward," Mr Matthews said.
The performance and reliability of the buses will be compared "like for like" with the diesel buses.
The trial buses will be slightly smaller than ordinary ACTION buses and be significantly quieter.
The electric buses will recharge overnight at their home depot, Tuggeranong, while the hybrid uses an on-board diesel engine to recharge an electric battery which runs the motor.
They have a range of about 450 kilometres - an ACTION bus does about 350 kilometres per day - and will transmit data live to help evaluate their efficiency.
Mr Matthews said they'd like passengers to share feedback about the buses, which will be launched officially later this month,
Ms Fitzharris will also outline in the ACT Legislative Assembly on Tuesday a future network of bike shares throughout Canberra.
Bike banks will be placed at bus and tram stops to further integrate the ACT public transport network.