Origin Energy drops Minimum Generation levels at Eraring Power Station to 180MW

Earlier this week Origin Energy organised a tour of the Eraring Power Station for a few energy-focused journalists … as a result of which we’ve seen a number of news articles written including the following:

1)  In the AFR we saw:

(a)  Angela Macdonald-Smith wrote ‘Origin reworks coal power stalwart for final years’.  In this article Angela wrote:

‘About two weeks ago, Origin finally received approval from the Australian Energy Market Operator to reduce the run rate at each unit to 180 MW when needed, just 25 per cent of their current maximum capacity of 750 MW.’

… with mention of ‘run rate’ it’s useful to remind readers of the difference between a megawatt (MW) and a megawatt hour (MWh).

2)  In the Australian we saw:

(a)  Colin Packham wrote ‘How Australia’s largest coal-fired power station encapsulates the energy transition’; and also

(b)  Colin Packham also wrote ‘Australia’s largest power station, Eraring, secures approval to run at lower minimum output’., with this article noting:

‘Australia’s biggest coal-fired power plant has received approvals to dial down its electricity supplies to cope with surging solar and wind generation, boosting its chances of staying open until 2029 to help ease a rocky path to a renewables-dominated grid.’

… remember that, in the extension agreement from 23rd May 2024, the commitment was to extend until at least August 2027 and possibly out till August 2029.

3)  In the Guardian, we saw:

(a)  Peter Hannam wrote ‘Inside Eraring, the giant coal-fired power station that escaped a 2025 death sentence’.

4)  No doubt it was mentioned elsewhere, as well…

Curiosity grabbed hold, so utilised the ‘Trends Engine’ in ez2view* to put together the following quick analysis.

* note that there’s a simpler version of the ‘Trends Engine’ in NEMreview v7 that also allows clients to produce this analysis.

Daily stats (for ER01) for the past ~2 years

Here’s a trend of daily statistics for ER01 (Eraring Unit 1) since the start of January 2023 … >21 months ago now:

Those with a licence to the software can open their own copy of this query here.

Eagle-eyed readers will see that this unit’s been running with Targets down to 180MW on occasions since 5th December 2023 … so some months before the AEMO approvals that Angela noted in her article.  Presumably this gap in time was related to testing processes.

1)  Prior to that reduction, the ‘minimum generation’ level (sometimes called ‘minimum load’) was down at 210MW.

2)  I’ve not looked at the other units, but presume the transition was roughly the same.

3)  That 120MW reduction in Min Load levels across the 4 units will flow through to:

(a)  The ability to get out of the way of more rooftop PV injections … especially on days like 1st September 2024:

i.  When Underlying Demand was low (due to seasonal factors); and, in conjunction

ii.  When ~80% of Large Solar generation potential was curtailed; and

ii.  When ~54% of Wind generation potential was curtailed.

(b)  But also could provide additional revenue boost (depending on hedge levels) if Origin is paid on the spot (i.e. when spot prices are negative) for providing hedge cover (above its lower min load) to its counterparties.

… that was one point Tim Nelson made in his talk earlier this week at the CEC’s AWIS.

Monthly stats (for ER01) for the ~25 years

Cranking the handle back till the start of 2000 and chunking the data up to monthly stats, we see the following trend over ~25 years of NEM history (still for the ER01 unit):

In this trend we see that:

1)  There were several points in the past that the unit peak capacity (either Registered Capacity or Maximum Capacity … note the difference) has been increased; and also

2)  That in the early part of the NEM it looks like there might have been some technical limitation (under certain circumstances) down at ~230MW … but I’ve not investigated further.

Current outages

Finally, let’s add this snapshot from the ‘Generator Outages’ widget in ez2view at the 15:00 dispatch interval today:

With respect to the above:

1)   Some of the articles above also talk about the (pretty major!) Planned Maintenance Outage underway at ER03 (Eraring unit 3) currently, with the return-to-service date currently out at 11th November 2024 … another 60 days away.

2)  We also see a shorter notice Unplanned Maintenance Outage coming up imminently for ER04 (Eraring Unit 4) for reasons I’ve not investigated.

That’s all for now…