Environment Minister Sussan Ley has given the gas-fired Kurri Kurri power plant the final tick of approval, paving the way for work to start on the $600 million project.
The NSW government approved the controversial project's environmental impact statement late last year and, given the plant is the government's idea, Ms Ley's approval comes as no surprise.
The start date for work will remain unclear until proponent Snowy Hydro signs a construction contract, but the government has said the new 660-megawatt plant will begin operating next year.
Ms Ley and Energy Minister Angus Taylor will be at the plant site outside Kurri Kurri on Monday morning to announce the approval.
The media event will give the two cabinet ministers another opportunity to highlight what the government sees as Labor's "humiliating backflip" over the project.
Labor opposed the power station when it was announced last year but said last week that it would build the plant as long as it ran on 30 per cent green hydrogen when it opened and 100 per cent green hydrogen by 2030.
The government has foreshadowed introducing hydrogen to the plant at some point in the future.
"Unlike Labor, the Morrison government has a concrete, costed and commercial plan for delivering this important electricity project," Mr Taylor said.
Opposition leader Anthony Albanese said last week that a Labor government would spend an extra $700 million on the plant so it could run sooner on hydrogen, pushing its sticker price as high as $1.3 billion.
The government's environmental impact statement showed the "peaking" plant would operate for two per cent of the time and employ 10 people.
The government believes the plant will help ensure stable and affordable electricity when Liddell power station closes next year, though some energy analysts and regulators have questioned whether it is necessary.
"The Morrison government is committed to delivering the Hunter Power Project on time and on budget to ensure there is no risk to electricity consumers after Liddell closes," Mr Taylor said.
"The project is good for jobs, it's good for business and, importantly, it's good for securing affordable, reliable power.
"It will support up to 600 direct jobs at peak construction and 1200 indirect jobs across NSW.
"The project is also vital to keep important businesses such as Tomago aluminium smelter operating."
Mr Taylor said Labor's plan would delay the project and double its cost.
Of the 261 submissions received during last year's public exhibition period, only two were in favour of the project.
