"I'm not ruling anything in or out," Premier Dominic Perrottet told reporters on Thursday, when asked about the possibility of looking into small modular reactor technology.

"When it comes to technology, I'm agnostic."

His comments come after NSW Treasurer Matt Kean said the reactors could be something the government considers as prototypes become available in 2030.

"When it comes to energy security, you can't rule anything out. You've got to be open minded right across the board," Mr Perrottet said.

"As a government what we're focused on is making sure we have downward pressure on prices in the short term, and energy security in the long term."

The premier stressed that his focus in the short term was getting the multi-billion dollar Narrabri gas pipeline project completed.

"Of course we'd be open to looking at options like nuclear if they were commercially available," Mr Kean told 2GB on Thursday morning.

"Small modular nuclear reactors are exciting technology, which may become available in the future."

Earlier this year, Mr Kean criticised his federal Liberal counterparts for attempting to overturn two federal bans on creating nuclear energy, accusing the party of "chasing unicorns".

Mr Kean called the plan a "fantasy" at the time, saying the technology was too far off to be considered a viable option.

The remarks by the Liberal premier and treasurer come as their federal party colleagues move closer to forming their own nuclear power policy for the next election, after convening a two-day forum on the energy source last month.

NSW Labor's environment spokeswoman Penny Sharpe criticised the comments, saying the state government needed to clarify where it stood on nuclear.

"(Nuclear) should not be part of our future. It is too expensive and it will take too long," she told reporters.

The government should be focused on getting renewable energy sources up and running across the state, she added.

NSW Labor is opposed to nuclear reactors being established in the state.

Australian Associated Press