This 19th Case Study in the series investigates one dispatch interval showing extreme Aggregate Under-Performance across all Semi-Scheduled units on Friday 5th April 2019.
This 18th Case Study in the series investigates two separate dispatch intervals showing extreme collective under-performance across all Semi-Scheduled units on Monday 25th March 2019.
This 16th Case Study in a series covers the first ‘extreme event’ into 2019 where there was an aggregate under-performance (compared to Target) across all Semi-Scheduled plant totaling greater than 300MW.
Prompted, in part, by yesterday’s record low for Victorian demand, today I have finished off my earlier review of what happened on Saturday 29th August (8 days earlier) when demand levels also dropped in VIC, and right across the NEM.
Out of curiosity, and driven by questions received from several people, I’ve invested a bit of time today to delve further into the record low level of Scheduled Demand seen in the Victorian region (and perhaps also across the whole of the NEM) on Saturday 29th August 2020.
This 15th Case Study is longer than the earlier 14 as it deals with 4 discrete instances of extreme level of collective under-performance, and 1 instance of over-performance, all within a 4-hour timeframe on the same day. A day which appears to have had widespread weather activity affecting the output of BOTH Wind and Solar across 3 Regions. A challenging day!
This is the 13th Case Study in this series (looking at each of 98 extreme incidents). We’re looking at an event on 15th October 2018 that seems to heavily feature high-wind cut-out as the primary driver for collective wind farm under-performance.
This is the 13th Case Study in this series (looking at each of 98 extreme incidents). Note I have skipped 2 events earlier in 2018 and will come back to publish case studies of them – this one covers the last event in 2018.
This is the 12th Case Study in this series (looking at each of 98 extreme incidents). This one is simpler than the 11th Case Study!
Some quick notes today, to document high-level data (to be explored later) relating to some significantly depressed solar harvest data today due to the widespread cloud/wind event.
This 9th case study in this series advances us into October 2017, where we see another example of an extreme outcome for collective under-performance. Most notably this happens across 5 Wind Farms (with one unit completely tripping).
This 8th case study in this series presents tabular results for all Semi-Scheduled DUIDs which were operational at the time of the SA System Black event.
This 7th case study in a series takes a look at 1 of 3 dispatch intervals during 2016 that saw extreme under-performance (in aggregate) across all Semi-Scheduled plant.
This 6th case study in a series takes a look at only 1 of 5 Dispatch Intervals featuring over-performance in a total of 98 that saw extreme Aggregate Raw Off-Target performance across all Semi-Scheduled plant (rare over-performance and more common under-performance).
For the 5th Case Study in this series (looking at individual outcomes of extremes in aggregate Raw Off-Target performance across all Semi-Scheduled plant) we look at an even rarer time when the aggregate discrepancy was above 400MW. This time collective under-performance.
After publishing three Case Studies on Saturday, this 4th Case Study in a long series is much more complex – with 8 different Semi-Scheduled Wind Farm units across VIC and SA exhibiting significant deviations from Target. This Case study looks at April 2016, which is also 3 years after the first 3 case studies.
Third case study today – and last one looking back at 2013. This one is a bit more complex than the first two.
Like was the case on 4th July 2013, the cause of this large Aggregate Raw Off-Target result (across all Semi-Scheduled Generators) was a single unit trip.
Does not take long to see why this particular dispatch interval was one of the few dispatch intervals (before 2019!) flagged in our top-down analysis of aggregate Raw Off-Target across all Semi-Scheduled units in the NEM….
Following on from the article posted on the day, here’s a focused look at what can be seen in (‘next day’ public) data for Yarranlea Solar Farm on Friday 1st May 2020 – a day that saw negative prices through many half-hour trading periods in Queensland, and Large Solar farms cycling as a result.