Spot prices for the week averaged between $22/MWh in New South Wales and $37/MWh in Queensland. Prices were consistent with the previous week in all regions except Queensland, where average prices more than doubled following higher than expected demand and rebidding on Tuesday.
Turnover in the energy market was $104 million. The total cost of ancillary services for the week, including Tasmania, was around $350 000, or 0.3 per cent of energy market turnover.
Significant variations between actual prices and those forecast 4 and 12 hours ahead occurred in 43 or around 13 per cent of all trading intervals. Demand forecasts produced 4 and 12 hours ahead varied from actual by more than 5 per cent in around 15 per cent of all trading intervals across the market. These variations were most frequent in South Australia occurring in almost two thirds of all trading intervals.
The AER welcomes comments on the information contained in, or the layout of, the report. Comments should be sent to Peter Adams or Mark Wilson, AER, GPO Box 922, Adelaide SA 5000 (email AERInquiry@aer.gov.au; fax (08) 8213 3414).
Figure 1 sets out national demand and spot prices in each region for each trading interval. Figure 2 compares the volume weighted average price with the averages for the previous week and the same quarter last year. Figure 3 compares the weekly price volatility index on the same basis.
Figure 1 National demand and spot price all regions
Figure 2 Volume weighted average spot price for energy market ($/MWh)
Maximum spot prices reached $58/MWh in New South Wales, $65/MWh in Victoria and $126/MWh in Tasmania, all occurring during the evening peaks. The maximum price in Queensland was $3359/MWh as a result of higher than expected demand, lower than forecast capacity and rebidding into higher prices. The maximum price in South Australia of $967/MWh occurred following a step reduction of the Victoria to South Australia (Heywood) interconnector to 250 MW for two 5-min dispatch intervals on Monday. The reduction was the result of a short duration network outage.
At 1.30 am on Friday and Saturday morning the spot price in Queensland fell to $-156/MWh. On both occasions this occurred as a result of a step reduction in export capability with maximum exports southwards and falling demand, leading to a $-1000/MWh five-minute dispatch price.
There was no low reserve conditions forecast.
A direction was issued in Tasmania for around 45 minutes on Tuesday following a SCADA failure. The generator was directed to provide frequency control.
The total cost of ancillary services on the mainland for the week was $319 000 or 0.3 per cent of the total turnover in the energy market on the mainland.
Figure 4 Volume weighted average frequency control ancillary service prices (excluding Tasmania)
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
1.52
0.72
1.56
1.58
0.21
0.29
0.65
1.83
Previous week ($/MW)
0.74
0.33
0.83
1.4
0.18
0.19
0.4
1.4
Last quarter ($/MW)
1.76
0.73
1.15
1.54
0.39
2.28
5
1.93
Market cost($1000s)
80
38
106
35
2
3
16
40
% of energy market
0.08%
0.04%
0.11%
0.04%
0%
0%
0.02%
0.04%
The total cost of ancillary services in Tasmania for the week was $34 000 or 0.5 per cent of the total turnover in the energy market in Tasmania.
Figure 5 Tasmanian volume weighted average frequency control ancillary service prices
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
2.11
0.12
0.23
0.17
0.26
0.1
0.1
0.11
Previous week ($/MW)
1.16
0.8
5.04
2.16
1.73
0.01
0.01
0.42
Last quarter ($/MWh)
7.89
1.05
1.05
1.58
4.43
1.06
1.06
1.97
Tasmania Market cost($1000s)
18
1
3
1
4
3
2
1
% Tasmania of energy market
0.27%
0.02%
0.04%
0.02%
0.06%
0.05%
0.04%
0.01%
Figure 6 shows the daily breakdown of price for each frequency control ancillary service. It also includes the cost of services sourced locally and in Tasmania.
Figure 6 Daily frequency control ancillary service prices
Figure 7 shows the weekly participation in each of the ancillary service markets on a regional basis.
Figure 7 Regional participation in ancillary services
Figures 8 and 9 show 30-minute prices for each of the ancillary services.
Figure 8 Prices for raise services
Figure 9 Prices for lower services
Figures 10 and 11 show the 30-minute Tasmanian price for each of the ancillary services.
Figure 10 Tasmanian prices for raise services
Figure 11 Tasmanian prices for lower services
Figures 12 and 13 present both the raise and lower requirements for each service over the week.
Figure 12 Raise requirements
Figure 13 Lower requirements
Figures 14 and 15 present both the raise and lower Tasmanian requirements for each service over the week.
