In Queensland we experienced one of the mildest summers I can remember. As a result of this, demand levels were subdued for most of summer. However, for a couple of days in late February, summer finally arrived, and struck with a vengeance.
Following from the interest generated in the article published in the AFR, we completed some analysis of the trend in IRPM over the history of the NEM up until June 2007.
The results of this analysis revealed that at no time before 2007 had the IRPM even dropped below 12% and that, except for the 2-day period (19th and 20th June) the IRPM had not dropped below 10%.
For two remarkable winter evenings in 2007 (19th and 20th June specifically) NEM-Wide Instantaneous Reserve Plant Margin (IRPM) plunged to the lowest levels ever seen in the NEM (a mere 7.6%) as generators were caught short of capacity by a…
There was a temperature-driven spike in demand across the NEM later in the week beginning Sunday 7th January – culminating in the summer’s first demand peak above 30,000MW (on Thursday 11th January).
On this occasion, the spot price spiked above $1000/MWh in Queensland, NSW, Snowy and Victoria,
There was a temperature-driven spike in demand in South Australia on Friday 8th December 2006.
However, demand also spiked on other days in the week, and on those occasions did not lead to the price spikes seen on the Friday.
For several days in early December, temperatures reaching 40 degrees in Queensland and New South Wales cause airconditioning load (and hence total demand) to soar in both regions.
The high demands resulted in very high prices being experienced in both QLD and NSW (and also the SNOWY region). Both VIC and SA were insulated from the high prices because (at least in part) of the fact that transfers over the SNOVIC interconnector were constrained to minimise negative inter-regional surplus
From the start of the NEM through until 2001, the NEM was typified by a pricing dichotomy with sustained rock-bottom pricing in NSW, Snowy and Victoria and high and volatile pricing in the extremities (Queensland and South Australia).
In 2001, the QNI interconnection and many generation projects were developed. This led to the convergence of prices between all regions, and the disappearance of price volatility – circumstances that were a real threat to generator profitability.
In response, generators adopted an approach that came to be known as “the economic withholding of capacity” to engineer volatility into the market throughout winter 2002 – and hence higher prices as a result., and generator behaviour.
There was a high level in demand in Victoria on Thursday 26th January 2006.
This was especially remarkable, considering that it was an Australia Day public holiday – when commercial (though not industrial or residential) demand could be expected to be somewhat lower than would otherwise be the case.
Coupled with this level of demand was a significant spike in price that lasted several hours.
This week saw a new record demand in NSW of 13,292MW on Thursday 2nd February. Correspondingly, average prices were above $100/MWh in both NSW and Queensland – but the price spikes did not transfer to the southern regions.
Demand in Victoria peaked again, bringing with it high prices in Victoria and (to a lesser extent) South Australia.
Indeed, the demand experienced in Victoria (on Friday 24th February) exceeded the previous high level of 8,552MW for summer, set in January 2006.
Our analysis looked at generator behaviour on the occasions of these price spikes.
Based on forecasts NEMMCO had been providing through their PASA process, we expected that it might prove that this week would deliver huge demand levels, and high prices.
Not to disappoint, the market did deliver high levels of demand in all regions:
(a) Peak demand levels were reduced somewhat from the huge levels the previous week in Victoria and South Australia;
(b) Demand levels were also still building to the record level to be experienced the following week in NSW;
(c) Peak demand levels in Queensland were fairly steady (and high) for most weeks of summer.
(d) In combination, a new NEM-wide peak demand target of 30,994MW was set on Monday 23rd January.
Summer 2005-06 saw Australians sweltering in temperatures 40 degrees and above.
In the National Electricity Market, this led to new peaks in demand and (given the tight supply/demand balance) delivered high (and volatile) spot market pricing.
Here we have compiled a weekly summary of events in the NEM over summer 2005-06.
The week started with commotion in Queensland, when the VOLL price ceiling was reached.
Further analysis revealed that this was due to transmission system events and the trip of several generation units within Queensland.