Surging rooftop solar panel installations and improved energy efficiency will push down the amount of power sold in the South West for the first time since at least 2006, according to the operator of the electricity market.

The Australian Energy Market Operator predicts power sales will decrease an average 0.4 per cent a year over the next decade, reversing its prediction last year of 0.9 per cent annual growth.

In the WA Electricity Statement of Opportunities, to be published today, AEMO said power sold per residential customer had decreased 3.6 per cent a year because of more energy efficient devices, such as LED lighting and inverter reverse-cycle air conditioners, and continuing uptake of rooftop solar.

Solar panels have also reduced the summer peak in power bought on hot days, and last year the winter peak equalled the summer peak for the first time since WA’s energy market started in 2006.

AEMO general manager WA Cameron Parrotte said the market operator was working with government and industry to achieve a smooth transition to a low emissions future.

“The growth of renewable generation in WA continues to drive a paradigm shift in the power system,” he said.

AEMO predicts that by 2024 renewable energy will at times generate 65 per cent of the grid’s power — equal to the world’s highest penetration.

Rooftop solar, which is not centrally co-ordinated or monitored, can generate 1.1 gigawatts of power, more than the biggest generator on the grid and is expected to more than double in the next 10 years.

To better manage rooftop solar Western Power will spend $215 million over three years to install 238,000 advanced meters.

The State Government intends to issue a plan later this year to better integrate so-called distributed energy resources like solar panels and batteries into the South West grid.