Plans to use massive overhead powerlines rather than underground cables to connect renewable energy zones are the right approach despite community opposition, an inquiry has found.
A NSW parliamentary committee on Thursday released its report looking at the feasibility of "undergrounding" transmission infrastructure for renewable energy projects.
It gave the tick of approval to the current plan for constructing overhead transmission lines.
The report comes following controversy surrounding the $4.9 billion HumeLink project, which will connect Snowy Hydro 2.0 to Sydney and the wider NSW grid but will also cut through prime farmland and national parks.
Running the project underground would lead to substantial additional cost, lengthy delays and regulatory approval hurdles, committee members in favour of the plan said.
The existing HumeLink plan is expected to be finished by 2026, but underground cables could delay the project up to five years due to increased construction work, updates to the route and environmental assessments, the inquiry was told.
The report said the 328km transmission project was the only way to address the risks from coal power station closures from 2026 and putting it underground would delay it until well after this period.
"The last thing we want to do is to endorse the underground approach, only to have the delay mean that NSW is subject to blackouts," it said.
The projected cost of the overland link has already blown out from $3.3 billion to nearly $4.9 billion, however network operator Transgrid estimated the cost of the project could more than triple to $17 billion if the lines were put underground.
Ahead of the inquiry's findings, Premier Chris Minns confirmed the government would push forward with plans to construct overland transmission lines to deliver renewable energy from the eastern seaboard into the grid.
"(Undergrounding will) add cost, it's going to add delay, and it will put in jeopardy all of the renewable energy plans from federal and state governments," he told a business event on Wednesday.
"I can't in good conscience say 'yes, we're going to tick off on that and see prices increase' ... for businesses and households and everybody else in NSW."
Greens infrastructure spokeswoman and committee member Cate Faehrmann labelled the inquiry a "missed opportunity".
"It does not reflect the evidence that was presented to the committee, which was overwhelmingly against overhead transmission lines," she said.
Nationals MP Wes Fang slammed the inquiry as a "sham", while community opponents accused the state government of ignoring the advice of independent experts.
"It is a slap in the face for the hard-working and caring people of these communities who tried in good faith to offer workable alternative solutions, which were met with disdain," spokesman Michael Katz said.