Spot prices for the week averaged between $23/MWh in Queensland and $44/MWh in South Australia. Prices in Queensland diverged from the rest of the market as a result of an increase in low priced capacity in Queensland and reductions in export capability into New South Wales.
Turnover in the energy market was $144 million. The total cost of ancillary services for the week, including Tasmania, was $270 000, or 0.2 per cent of energy market turnover.
Significant variations between actual prices and those forecast 4 and 12 hours ahead occurred in 55, or around 16 per cent of all trading intervals. Demand forecasts produced 4 and 12 hours ahead varied from actual by more than 5 per cent in a third of all trading intervals across the market. These variations were most frequent in South Australia, occurring in over a half of all trading intervals.
The AER welcomes comments on the information contained in, or the layout of, the report. Comments should be sent to Peter Adams or Mark Wilson, AER, GPO Box 922, Adelaide SA 5000 (email AERInquiry@aer.gov.au; fax (08) 8213 3414).
Figure 1 sets out national demand and spot prices in each region for each trading interval. Figure 2 compares the volume weighted average price with the averages for the previous week and the same quarter last year. Figure 3 compares the weekly price volatility index on the same basis.
Figure 1 National demand and spot price all regions
Figure 2 Volume weighted average spot price for energy market ($/MWh)
Maximum spot prices for the week were $88/MWh in Queensland, $98/MWh in New South Wales and $88/MWh in Tasmania, all occurring at 6 pm on Tuesday. The maximum spot price reached $95/MWh in Victoria and $102/MWh in South Australia at 6.30 pm on Thursday.
On Friday, Queensland recorded a spot price of $-150/MWh following a change on the rating of the 82 line between Liddell and Tomago in New South Wales. This change in rating reduced Queensland exports into New South Wales by almost 600 MW in one 5-minute dispatch interval leading to a $-1000/MWh dispatch price at 7.10 am.
The total cost of ancillary services on the mainland for the week was $91 000 or 0.1 per cent of the total turnover in the energy market.
Figure 4 summarises the volume weighted average prices and costs for the eight frequency control ancillary services across the interconnected regions.
Figure 4 Volume weighted average frequency control ancillary service prices (excluding Tasmania)
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
0.5
0.09
0.59
0.97
0.15
0.05
0.26
0.87
Previous week ($/MW)
0.66
0.13
0.72
1.08
0.15
0.06
0.2
0.96
Last quarter ($/MW)
1.76
0.73
1.15
1.54
0.39
2.28
5
1.93
Market cost($1000s)
19
3
33
20
0
0
3
14
% of energy market
0.01%
0%
0.02%
0.01%
0%
0%
0%
0.01%
The total cost of ancillary services in Tasmania for the week was $175 000 or 2.2 per cent of the total turnover in the energy market in Tasmania. High prices occurred for lower 6 second services in Tasmania throughout the week, particularly on Wednesday.
Figure 5 summarises the volume weighted average prices and costs for the eight frequency control ancillary services across Tasmania.
Figure 5 Tasmanian volume weighted average frequency control ancillary service prices
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
3.28
0.32
0.69
2.36
32.15
0.05
0.4
0.81
Previous week ($/MW)
16.61
0.21
1.26
12.94
15.6
0.05
0.37
0.82
Last quarter ($/MWh)
7.89
1.05
1.05
1.58
4.43
1.06
1.06
1.97
Tasmania Market cost($1000s)
19
4
12
7
122
1
6
5
% Tasmania of energy market
0.23%
0.05%
0.14%
0.09%
1.5%
0.01%
0.07%
0.06%
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.
