Rooftop solar installed by Australian homes and businesses in on track to generate more than coal by 2040

Australia’s installed rooftop solar capacity in on track to generate between 31-50TWh of power across the National Electricity Market by 2040, and supply up to 22 per cent of national demand, a new report has found.

The report, the Australian Energy Market Operator’s recently released Integrated System Plan, puts distributed solar, or DER, on track to supply more power to the national grid than coal within little more than 20 years.

According to the ISP, rooftop PV generation will reach approximately 31TWh across the NEM by 2040 in its Neutral (below), Slow change, and Fast change scenarios, and nearly 50TWh in the high DER scenario.

This represents between 13 and 22 per cent of forecast total underlying NEM electricity consumption, the report says, and has the potential to “deliver a major cost saving to consumers.”

These savings would be greatest, of course, under the ISP’s High DER scenario, which considers a future where distributed rooftop PV generation, battery storage, and other demand-based resources
at the consumer level are higher than in the Neutral case.

“High DER scenario shows the potential for even greater use of DER to lower the total costs to supply, with the net present value of wholesale resource costs reduced by nearly $4 billion, compared to the Neutral case,” the report says
AEMO’s assumptions about rooftop solar gel with a recent report from Bloomberg New Energy Finance, which said the biggest threat to Australia’s legacy coal-fired generators was not wind and solar farms, or even the settings of the country’s emissions policy, but the continued boom in rooftop solar.
“There will be more capacity behind the meter than the total current capacity in the National Electricity Market (NEM),” lead analyst Kobad Bhavnagri said.

“It is a massive slab of capacity … and it will be the biggest single contributor to generation.”