2,880 megawatts. That’s the nameplate on Eraring, which makes it the biggest coal plant in the National Electricity Market by a comfortable margin, and it’s the number that sits behind every argument about what happens on the NSW central coast over the next eighteen months. Origin Energy owns it. Origin wanted it closed by August 2025. It isn’t closing then, or anywhere near it, and the reason why is a deal with the NSW government that’s worth sitting with properly rather than skimming past as background noise to the battery headlines.
I drove up the Pacific Highway past Dora Creek a few months back, the turnoff to the plant still signposted like nothing’s changed, and from the road you’d have no idea this is a facility whose retirement date has become a genuine piece of state energy policy rather than a line in a company’s asset register. That’s the first thing worth saying plainly: Eraring closing is not really Origin’s decision anymore, not in the way it would have been five years ago. It’s a negotiated outcome between a private gentailer and a state government that needed more time.
The deal in plain terms
Origin and the NSW government agreed, through an arrangement finalised in 2025, to keep Eraring running to August 2027 rather than closing it in 2025 as Origin had originally flagged back in 2022. The mechanism is a conditional financial support deed: the state effectively underwrites some of the downside risk of running the plant longer, with Origin retaining the upside if wholesale prices behave. It’s not a blank cheque and it’s not nationalisation by stealth; it’s closer to an insurance policy the state decided it needed, because the alternative was betting the central coast’s reliability on REZ transmission and batteries landing on a construction timetable that, as we’ve covered before in the context of the broader NSW coal exit and REZ rollout gap, has been slower than anyone in Macquarie Street would like to admit out loud.
Origin’s own ASX filings and investor updates have been consistent on the broad shape of this since the deed was struck: the extension runs to 2027, it’s reviewable, and it sits alongside a battery project on the same site. AEMO’s published reliability forecasts, in the Electricity Statement of Opportunities, are the document that actually forced the conversation: the agency flagged reliability gaps on the NSW coast that made an unmanaged 2025 exit look genuinely risky, not just politically awkward.
Why the closure date moved at all
Eraring was never going to close because the turbines wore out. Coal units in the NEM mostly don’t die of old age anymore; they get retired because the economics of running them stop working once enough cheap renewable generation is on the system pushing wholesale prices down in the middle of the day. That’s the pattern we’ve watched play out at Yallourn in Victoria, which is still working through its own 2028 closure and the battery racing to replace it, and it’s the same pattern behind Liddell’s exit a few years back.
The twist with Eraring is that NSW’s replacement pipeline (the Central-West Orana REZ, the Waratah Super Battery, transmission augmentation around Sydney) simply wasn’t far enough along to let the state wave the plant goodbye on the original schedule. AEMO said so, more or less, in its reliability work. The government looked at the numbers and decided two more years of a 2,880 megawatt baseload unit was cheaper, in risk terms, than finding out the hard way what a tight summer without it actually costs in load-shedding and political capital.
The battery on site
Origin’s battery at Eraring is the part of this story that gets the better headlines, and fairly enough: a large-scale battery on a retiring coal site is a tidy image for the transition, reusing the grid connection a coal unit spent decades paying for. The project has progressed in stages, with an initial tranche of capacity energised and further stages planned, building toward a facility in the high hundreds of megawatts with several hours of storage behind it. It’s one of several big batteries doing this kind of grid-connection recycling around the NEM, in the same family as the shock-absorber role the Waratah Super Battery plays further down the coast.
But I’d push back gently on the framing you sometimes hear, that the battery is “replacing” Eraring. It isn’t, not on the numbers. A battery with a few hours of storage behind several hundred megawatts of capacity is an excellent tool for smoothing the evening ramp and catching price spikes. It is not a substitute for 2,880 megawatts of near-continuous output across a cold week when the wind drops over three states at once. Anyone who tells you otherwise hasn’t done the arithmetic on energy versus power, which is the same confusion that trips up a lot of battery coverage generally, including some of the more breathless claims about whether big batteries are being built for the wrong job in the first place.
What 2027 actually buys
Two extra years is not a small thing in transmission-and-storage years. It’s roughly the gap between “REZ transmission corridors exist on a map” and “REZ transmission corridors exist with steel in the ground,” which matters more than people give it credit for. The Central-West Orana REZ has had its own delays, and NSW’s broader coal-exit timeline has been running ahead of the replacement build for a while now: a gap this masthead has tracked more than once, including in the straightforward stocktake of whether coal closures and the reliability debate have actually been resolved by anyone, anywhere, this decade.
The honest accounting is that the extension buys NSW time to finish transmission work, get more firming capacity connected, and let the Waratah battery and others like it build a longer track record before the state loses its biggest single generator. It does not buy certainty. The deed is reviewable, which means 2027 is itself not fixed in stone the way some coverage implies: if conditions change again, in either direction, that date could move once more. I’d be mildly surprised if it doesn’t get revisited at least once before August 2027 arrives, given how the last round of goalposts moved.
The reliability argument nobody fully settles
There’s a camp that says propping Eraring up is just delaying an inevitable and useful discipline – that giving coal more runway softens the incentive to get storage and transmission built at the pace actually required. There’s another camp, and AEMO’s own forecasting broadly sits in this camp, that says an unmanaged exit risked genuine supply shortfalls on the coast, the kind that show up as load-shedding on a 40-degree February afternoon rather than as an abstract modelling output.
Both are right, which is the annoying truth of most coal-exit arguments. Keeping Eraring running longer is a sensible insurance policy against a transmission build that has repeatedly missed its own deadlines. It is also, separately, true that an insurance policy you keep renewing starts to look like a permanent arrangement, and permanent arrangements have a way of blunting urgency elsewhere in the system. NSW energy planning doesn’t get graded on good intentions; it gets graded on megawatts actually connected by the date on the slide, and on that measure the state’s record over the past few years invites a bit more scepticism than the press releases suggest.
The wider pattern across the NEM
Eraring isn’t an isolated case; it’s the biggest and most visible example of a pattern that’s become almost routine in the NEM over the past five years: a retirement date gets announced, the replacement build runs late, and the plant gets a negotiated reprieve rather than a hard stop. Origin and AGL have both been through versions of this. The AEMC and AER have both, in different ways, pointed at the same underlying tension: the market was designed to let generators exit on commercial timetables, but reliability obligations increasingly pull governments into the middle of those decisions anyway, deed by deed.
Worth remembering, too, that this isn’t just an engineering story. Eraring directly employs several hundred people and supports a wider web of contractors and coal supply arrangements around the Hunter and central coast, and every deferral buys those workers more runway as well, which the EnergyAustralia experience at Yallourn suggests matters just as much to a region as the generation maths does.
So where does that leave the plant itself. Still the biggest coal station in the NEM, still running, still scheduled to close in 2027 unless that date moves again, with a battery on the same site quietly building the case that the location has a second act even after the boilers go cold. I’ll be watching the next AEMO reliability update as closely as anyone, not because I expect a surprise, but because the pattern so far suggests the surprise, if there is one, tends to arrive about six months before everyone thought it would.
– Tom Fitzgerald, Baseload & Fuels Correspondent