The Baird government has granted planning approval for four new large-scale solar plants, potentially more than doubling the existing capacity in the state.

The four plants approved for construction have a combined capacity of 175 megawatts (MW), and would generate another electricity for 56,000 homes if built.

"NSW is Australia's large-scale solar leader, with the country's three largest solar farms and hundreds of megawatts of solar electricity capacity online and in the pipeline," planning minister Rob Stokes said.

"We want to make people's lives better through good planning, and these projects will increase electricity capacity, cut greenhouse emissions and create jobs for local communities".

Building the plants would generate more than 330 new construction jobs, save 342,000 tonnes of greenhouse gas annually, and include more than a half a million solar panels between them, Mr Stokes' office said.

NSW is already home to AGL's two solar plants at Broken Hill and Nyngan, which are operating with a combined capacity of 155 megawatts. Also under construction is the 56 MW Moree solar farm, the largest now being built in Australia.

Solar energy is the one bright spot for renewables in NSW. Compared with other states, NSW has the second lowest share of clean energy as a total of its electricity, ahead of only Queensland.

So far this year, NSW has sourced 8.8 per cent of its electricity from renewable sources including rooftop solar - barely half Victoria's 15.8 per cent and a quarter of South Australia's 36 per cent, according to energy consultants Pitt & Sherry.

"The issuing of planning approvals is a positive development, but it does not automatically equate to more investment," Kobad Bhavnagri, head of Bloomberg New Energy Finance's Australian office.

"There are nearly 2000 MW of renewable energy projects with planning approval in NSW, yet in the last year only 175 MW have been financed and committed to construction."

Closing the gap

However, the state has the potential to close the gap, given a wind resource second only to South Australia's, sun-drenched inland regions and proximity to major markets and existing infrastructure.

"Solar is a key part of NSW's energy mix and will become even more important into the future. I'm delighted to see these projects getting the green light," Anthony Roberts, the energy minister, said.

The four new solar farms are the White Rock project with 20 megawatt capacity, one in Griffith for 60 MW, the Yoogali farm, also near Griffith, with 30 MW and a 65-MW plant for Parkes.

Most of the new plants would be among Australia's largest. Apart from the Moree plant, the next largest under construction now is a 25-MW plant at Barcaldine in Queensland, according to the Clean Energy Council.

Two other solar farms have had state approval since 2011: the Capital Solar plant in Bungendore with a capacity of 50MW and Manildra Solar Farm with a capacity of 42MW.

Joint Regional Planning Panels have also given approval for three other plants totaling 63 MW at Wagga Wagga, Temora and Dubbo.

Kane Thornton, chief executive of the Clean Energy Council, welcomed the latest proof that large-scale solar was "really cementing its place in Australia's electricity mix".

"The potential for large-scale solar right across Australia is massive, and these projects would help ensure NSW remains in the race for each state's share of renewable energy jobs and investment," Mr Thornton said.

That race is hotting up, with Daniel Andrews, Victoria's Labor premier, earlier this month announcing plans for his state to aim for 40 per cent renewable energy in its electricity sector by 2025.

South Australia's target is 50 per cent renewable energy in its electricity sector by 2025, while Queensland is aiming for that ratio by 2030. NSW's target is 20 per cent by 2020-21.

Federally, the Turnbull government has made no announcement about its post-2020 renewable energy target, while a Shorten government has promised to aim for 50 per cent by 2030.

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