Scott Morrison has unveiled a new tunnel boring machine, named Kirsten, at the Snowy Hydro 2.0 project.

"Snowy 2.0 is building on the proud legacy of the first Snowy scheme, using local ingenuity to deliver landmark new infrastructure that will benefit Australia and the national electricity market for decades to come," the prime minister said on Friday.

The 205-metre long machine is named in honour of astrophysicist, science communicator and Wiradjuri woman Kirsten Banks.

It has a diameter of around 11 metres, or the same as a three-storey building.

The machine will excavate a 2.9km-long tunnel to the power station complex and then continue to tunnel uphill at a 25-degree grade to create an inclined pressure shaft.

The first tunnel boring machine, the Lady Eileen Hudson, has already surpassed one kilometre underground.

The announcement came as federal parliament wrapped up for the year.

Australian Associated Press