Pace of 'big clean energy' rollout must at least double

A virtual power plant of rooftop solar was added to the electricity grid last year to slash crippling power bills, industry data shows.

Approximately 3.4 million homes are helping to reduce cost of living pressures and pressure on the energy grid during the summer peak, according to the Clean Energy Australia Report released on Tuesday.

Some 310,352 new rooftop solar systems were added, bringing almost the same capacity as Australia's biggest coal-fired power plant Eraring.

More than 50,000 home battery systems were installed, up from 34,731 in 2021, as households prepare to plug in more electric cars.

Only a tiny fraction (1.6 per cent) of solar households have storage installed, but battery prices are coming down and growth is tipped to follow.

In a record high for "big clean energy", the annual report found construction began on more than 5000 megawatts of wind and solar farms.

But it wasn't a bumper year for getting big projects completed as supply chain woes and labour shortages continue, and large-scale investment is coming online more slowly than required.

"To reach the federal government's renewable energy generation target of 82 per cent by 2030, the pace of deployment for new large-scale projects needs to at least double," Clean Energy Council CEO Kane Thornton said.

As large coal-fired plants prepare to close in NSW with years of warning to regulators, the state became the top jurisdiction for renewable energy generation at 21,765 gigawatt-hours.

The overall share of coal in the generation mix fell from 59.1 per cent in 2021 to 54.6 per cent in 2022, while gas increased from 7.7 per cent to 8.9 per cent. 

Renewable energy accounted for more than a third (35.9 per cent) of total electricity generation, and has more than doubled since 2017.

"There's significant cause for optimism at a time when ageing fossil fuel-based generators are retiring," Mr Thornton said.

Rooftop solar is adding around 3.5 terawatt hours per year, and the challenge is maintaining this pace through to 2030, he added.

Large-scale clean energy investment reached $6.2 billion in 2022, a 17 per cent increase from 2021.

Investors are anticipating the need for more utility-scale storage to secure the grid, with 19 large-scale battery projects under construction for a combined capacity significantly higher than the previous year.

The largest battery systems under construction at the end of 2022 included the 250MW Torrens Island Battery in South Australia and Queensland's 200MW Western Downs Green Power Hub.

Investment in financially committed large-scale generation and storage projects hit $4.29b in the last three months of 2022, for the second-highest quarterly result since data collection began in 2017.