Spot prices for the week were similar to the previous week and averaged $36/MWh in South Australia, $31/MWh in Victoria, $29/MWh in New South Wales and $22/MWh in Queensland.
In Tasmania the spot price averaged $117/MWh, slightly up on the previous week.
The price volatility index was higher than for the previous week across the mainland regions. In Tasmania, the volatility index reduced further, with the spot price only varying between $93/MWh and $130/MWh.
Turnover in the energy market was around $134 million, while the total cost of ancillary services for the week was $440 000 or 0.3 per cent of the total turnover in the energy market. The cost for ancillary services in Tasmania totalled $128 000 or 0.5 per cent of the energy market turnover for that region.
Demand forecasts produced four and 12 hours ahead varied from actual by more than 5 per cent in around a quarter of all trading intervals across the market with close to two-thirds of trading intervals in South Australia affected. The maximum error four hours ahead for under-forecasting demand was 17 per cent (or 260 MW) in South Australia, 8 per cent (800 MW) in New South Wales, 7 per cent (90 MW) in Tasmania and 6 per cent (360 MW) in Queensland and Victoria. These errors are similar to the size of the largest unit in most regions. Significant variations between forecast and actual prices occurred in 41 or 12 per cent of all trading intervals.
The analysis is provided for information only—it does not constitute business advice and should not be relied on as a substitute for obtaining detailed analysis or advice about the operation of the national electricity market. Neither the AER nor any of its employees make any representation or warranty as to the accuracy of the information in the analysis, or its conclusions.
The AER would welcome comments on the information contained in, or the layout of, the report. Comments should be sent to Peter Adams or Mark Wilson, AER, 14th floor, 13 Grenfell Street, Adelaide SA 5001 (email peter.adams@aer.gov.au; mark.wilson@aer.gov.au; fax (08) 8213 3414).
Figure 1 sets out national demand and spot prices in each region for each trading interval. Figure 2 compares the volume weighted average price with the averages for the previous week and the same quarter last year. Figure 3 compares the weekly price volatility index on the same basis.
Figure 1 National demand and spot price all regions
Figure 2 Volume weighted average spot price for energy market ($/MWh)
Spot prices peaked at $270/MWh in South Australia and New South Wales, $240/MWh in Victoria and at $180/MWh in Queensland, all on Sunday evening. In Tasmania the spot price peaked at $130/MWh on Saturday morning.
There were no low reserve conditions forecast throughout the week.
The total cost of ancillary services for the week was $440 000 or 0.3 per cent of the total turnover in the energy market. A planned transmission outage in Victoria on Sunday, and for a number of short periods throughout the week, resulted in an increased requirement for lower contingency services.
The cost for ancillary services in Tasmania totalled $128 000 or 0.5 per cent of the energy market turnover for that region.
Figure 4 Volume weighted average frequency control ancillary service prices (excluding Tasmania)
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
1.29
0.58
0.87
1.44
0.17
1.56
2.57
1.79
Previous week ($/MW)
1.36
0.51
0.85
0.96
0.18
1.45
2.26
1.6
Last quarter ($/MW)
2.43
0.81
0.99
1.07
0.23
0.96
2.96
1.51
Market cost($1000s)
64
29
58
34
1
17
64
42
% of energy market
0.03%
0.01%
0.03%
0.02%
0%
0.01%
0.03%
0.02%
Figure 5 Tasmanian volume weighted average frequency control ancillary service prices
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
1.48
1.05
1.06
1.36
1.06
1.05
1.05
1.05
Previous week ($/MW)
2.75
1.05
1.06
1.28
1.06
1.05
1.05
1.05
Tasmania market cost($1000s)
15
11
12
11
13
31
26
9
% Tasmania of energy market
0.06%
0.04%
0.05%
0.05%
0.06%
0.13%
0.11%
0.04%
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 or 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.
