The main grid operator in Australia is preparing for what will be a global novelty: meeting 100% of the demand for renewable energy, almost all wind and solar.
It will be a historic achievement for a grid of this size, which is not linked to another grid and features a unique elongated network running from north to south along the east coast, with a detour to South Australia.
The operator of the Australian energy market expects that from 2025 100% renewable moments will begin to occur “instantly” on several occasions – the highest it has been so far is 61.8% last November – and is quickly preparing their systems and knowledge. to ensure that the network remains stable when they occur.
It will be a kind of landmark, especially for a grid of this size, and one that is not linked to others and has a unique elongated network that runs from north to south along the east coast, with a detour to Australia. Southern.
But the biggest question for many people is whether and how quickly the Australian grid can switch to 100% renewable energy, not just in multiple cases, but annually.
The latest integrated systems plan released by AEMO this week draws some tempting scenarios, with the scenario currently considered most likely, the change of pace, reaching a 90% share of renewables in the early 2040s when the ‘latest coal generator goes off the grid.
But in the Step Change scenario, considered most likely by the majority of the 1,500 stakeholders consulted by AEMO over the past two years, the share of renewables never reaches 100%.
The reason, says AEMO CEO Daniel Westerman, is that the cost of shutting down the last percent of fossil fuel generation with renewables and storage is very high, and much more than the cost of transitioning from the first 95 or 96 percent.
“The cost difference between a clean zero system and a zero zero system is pretty staggering,” Westerman told RenewEconomy in an interview this week.
“What the modeling shows is that removing this gas (or hydrogen or biogas equivalents) and achieving that capacity in utility batteries is very expensive and very difficult.”
To be clear, Westerman has no doubt that wind and solar and storage, what he calls “confirmed renewables,” is by far the cheapest way to get to a low-carbon grid. And he says the current global energy crisis only amplifies the need and urgency to make change.
It’s just that overcoming the last percent has long been recognized as the hardest part of the transition to 100 percent renewable.
This is mainly due to the storage costs that would be required as a contingency for those tariff moments when there is not enough wind and solar generation or stored to meet demand.
That’s why AEMO’s roadmap still considers conventional-style peak generators in the system to fill these critical gaps, which may also include the so-called “dunkelflaute,” the German word for seasonal wind breaks. and the lot.
The change of pace plan envisages that up to 10 GW of gas plants with a maximum point will be maintained in the system by 2050. They are unlikely to be used much, but this figure has surprised many energy analysts.
Westerman says having peak generators in the system does not necessarily mean using fossil gas. It is also very likely that these generators use biogas or hydrogen. This, he says, marks the difference between “zero net” and “zero zero,” which refers to zero carbon-only generation.
According to the AEMO model, the scenario that does provide for 100% of renewables is the hydrogen superpower scenario, which includes the production of green hydrogen not included in the changeover scenario. .
This suggests that the proportion of renewable energy is rapidly boosting to 90% in a decade, as tens of gigawatts of new wind and solar are deployed to meet the demand for green hydrogen and ammonia production for steel. green and other green industries, and possibly green. exports.
This scenario is already considered most likely by almost a fifth of the 1,500 energy experts consulted by AEMO, but is expected to become the “most likely” by most experts in a few years, as green hydrogen planes are beginning to take shape.
In this scenario of hydrogen superpower, Australia’s grid reaches 100% of renewables in the early 2040s. That’s when any hydrogen generation that is used to fill these renewable energy droughts s will feed completely from wind and solar.
Giles Parkinson is the founder and editor of Renew Economy, and is also the founder of One Step Off The Grid and the founder and editor of The Driven, which focuses on EV. Giles has been a journalist for 40 years and is a former business editor and adjunct of the Australian Financial Review.