Rooftop solar to meet 3/4 of demand by 2026

Rooftop solar, Australia

 From IEEFA

Rooftop solar systems are going to have such an impact in coming years that they will meet up to 77 per cent of total grid demand on occasions within five years, sending minimum operating [i.e., net] demand down to levels that had never been contemplated until recently.

The Australian Energy Market Operator says the pace of rooftop solar is increasing beyond its own expectations and homes and businesses will likely add at least another 8.9GW by 2025, on top of the existing capacity of 14GW.

This will have a major impact on prices, demand and the operations of the grid. These solar systems alone could supply up to 77% of total electricity demand at times by 2026 in the four mainland states that are part of the National Electricity Market (South Australia, Victoria, NSW and Queensland).

“As a result, minimum operational demand across the NEM mainland is expected to drop to a record low of 4 to 6GW by 2025, down from 15GW in 2019,” AEMO says.

This is a real Ozzie success story, which has happened despite the Right's slavish devotion to their fossil fuel masters.  And it happened because a leftish government introduced subsidies for small-scale/rooftop solar.    The subsidies drove rapid take-up, and this in turn drove down the before-subsidy costs in a classic learning curve virtuous cycle.  These days, one can put 5 kW of panels on one's roof for ± A$5000 (US$3500). It also made people aware of renewables; so much so, that when one talks about solar, everybody thinks one means rooftop solar.

The tremendous growth of rooftop solar (3 GW in 2020 alone) has meant that some aging poles-and-wires street infrastructure is stressed on sunny days, and the grid operators, ever alert for more cash, are trying to get a "solar charge" introduced because "it's not fair".  Ignoring of course that the wholesale price of electricity has been driven down by the jump in renewables in the system, reducing electricity costs for everyone, not just those with rooftop panels.   Meanwhile, on hot, sunny days, local solar actually saves the wider grid from being overloaded (and shutting down) when all the aircon units on individual houses are run., because typically, it's sunny when it's hot.  Duh.      

The obvious solution to overloading the poles and wires, which in fact existed when I put in my first set of solar panels a decade ago. is a smart meter, which disconnects the solar panels from the grid when the voltage on the local grid rises too high, stopping the grid from burning out.   

The key point I want to make though, is this: Australia went from zero solar to 77% (on sunny days) in little over a decade.  Similar subsidies and targets could drive behind-the-meter household storage to high enough levels to stabilise the grid; and also EVs to 100% of sales.  Within 15 years.  Subsidising/incentivising a technology which has a steep learning curve drives very rapid increases in installations.  Not gonna happen in Oz, given our troglodytic backward LNP government, so don't hold your breath.