However, the fleet is still waiting on the all-important refuelling station to open for business.

The 20 Hyundai Nexo hatchbacks will be fuelled out of the nation's first public hydrogen refuelling station being prepared by ActewAGL in Fyshwick.

The zero emission cars will be leased to the ACT government through SG Fleet although no decision has been made yet on which ACT government directorates will be using the vehicles.

The Nexo fuel cell car has a driving range of 666 kilometres and has a refuelling time of between three to five minutes, unlike the government's Ioniq electric vehicles, which take between 40 minutes for a short-range charge and up to eight hours for a full charge.

The ACT government's hydrogen car program has been championed by Sustainability Minister Shane Rattenbury, who is taking a calculated punt on the technology being more widely adopted nationally in the years ahead and wants Canberra to take a lead role.

French renewable energy supplier Neoen is providing the power to run the ACT hydrogen-making process from the Hornsdale Wind Farm and its associated 100-megawatt Tesla lithium-ion battery storage.

While filling up a Nexo with hydrogen takes much the same time as filling the tank of a conventional car, the connection from the bowser to the car's fuel tank has to be highly secure and completely leak-proof because of the fuel's volatility and the 600 bar of refuelling pressure.

Hydrogen is seen as the "end game" future fuel to replace conventional fossil fuels but the cost of producing it is still expensive.

The fuel capacity of the Nexo is measured in kilograms, not litres like petrol and diesel. The vehicle's tank capacity is 6.3 kilograms, which means each kilogram of fuel provides a little over 100kms of driving range.

ActewAGL is coy about revealing how much the fuel costs per kilogram at Canberra's station but points out that the power to produce it comes from a renewable source.

In the US, where the fuel has been available to the transport sector for some years, it costs up to US$16 per kilogram.

The only emission from a hydrogen car is water vapour and the Nexo has a maximum five-star crash rating from Australia's ANCAP vehicle safety authority.

The sticking point for ActewAGL, which will operate the refuelling station, is the commissioning of the complex Fyshwick electrolysis plant.

The specialist US engineers who perform the task had been due to work on the commissioning during May and June but this was delayed due to the COVID-19 international travel restrictions.

Lennock Hyundai dealership in Phillip will provide service and support for the ACT fleet, and Hyundai Australia has trained up several service specialists to do this work.

The ACT public servants who will drive the cars will also be given a briefing on the vehicles, although aside from the refuelling process the cars will drive and operate much the same as the government's electric vehicles.

Canberra will commission its public refuelling station ahead of others planned later this year for NSW, South Australia, Western Australia and Tasmania.

Australia's National Hydrogen Strategy was unanimously endorsed by the Council of Australian Governments (COAG) at the end of 2019, and aims to have a widespread supporting network of refuelling stations in place by 2030.