Spot prices for the week averaged between $67/MWh in Victoria and $75/MWh in New South Wales. A significant reduction in the amount of capacity offered at prices of less than $20/MWh, compared to the same period last year, resulted in spot prices well above the April average. Planned reductions for generator maintenance, typical of this time of year, saw as much as 5900 MW of capacity removed from the market. This coincided with the reduced availability of hydro and coal fired capacity as a result of the drought, and the repricing of capacity for commercial reasons, which also contributed.
Turnover in the energy market was $265 million. The total cost of ancillary services for the week was $894 000, or 0.3 per cent of energy market turnover.
Significant variations between actual prices and those forecast 4 and 12 hours ahead occurred in 124 or a third of all trading intervals. Demand forecasts produced 4 and 12 hours ahead varied from actual by more than 5 per cent in around a fifth of all trading intervals across the market. These variations were most frequent in South Australia and Tasmania, occurring in more than a third all trading intervals.
The Australian Energy Regulator welcomes comments on the information contained in, or the layout of, the report. Comments should be sent to Peter Adams or Mark Wilson, AER, GPO Box 922, Adelaide SA 5000 (email AERInquiry@aer.gov.au; fax (08) 8213 3414).
Figure 1 sets out national demand and spot prices in each region for each trading interval. Figure 2 compares the volume weighted average price with the averages for the previous week and the same quarter last year. Figure 3 compares the weekly price volatility index on the same basis.
Figure 1 National demand and spot price all regions
Figure 2 Volume weighted average spot price for energy market ($/MWh)
The total cost of ancillary services on the mainland for the week was $362 000 or 0.1 per cent of the energy market.
Figure 4 summarises the volume weighted average prices and costs for the eight frequency control ancillary services across the interconnected regions.
Figure 4 Volume weighted average frequency control ancillary service prices (excluding Tasmania)
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
2.43
0.63
1.64
3.42
0.17
0.35
1.27
1.32
Previous week ($/MW)
0.83
0.28
0.85
2.18
0.06
0.53
1.23
1.38
Last quarter ($/MW)
1.76
0.73
1.15
1.54
0.39
2.28
5
1.93
Market cost($1000s)
114
26
98
75
1
3
23
21
% of energy market
0.05%
0.01%
0.04%
0.03%
0.01%
0.01%
0.01%
0.01%
The total cost of ancillary services in Tasmania for the week was $532 000 or 4 per cent of the total turnover in the energy market in Tasmania. Early on Thursday morning, the cost of lower 6 second services increased to $10 000/MW for two dispatch intervals. At the time, Basslink was operating in the no-go zone and as a result was unable to transfer FCAS from the mainland. Since Hydro Tasmania could not supply the entire Tasmanian requirement, the price for that service was set to the price cap. Once through the no-go zone Basslink could transfer FCAS and the price returned to previous levels. This event cost $154 000.
Figure 5 summarises the volume weighted average prices and costs for the eight frequency control ancillary services across Tasmania.
Figure 5 Tasmanian volume weighted average frequency control ancillary service prices
Raise
Lower
6 sec
60 sec
5 min
Reg
6 sec
60 sec
5 min
Reg
Last week($/MW)
19.54
2.21
3.59
5.9
39.64
7.69
4.32
1.45
Previous week ($/MW)
3.5
1.06
1.41
2.31
0.03
0.35
1.22
0.91
Last quarter ($/MWh)
4.97
0.49
2.93
3
12.67
0.43
0.82
0.45
Tasmania Market cost($1000s)
72
22
39
23
194
113
63
6
% Tasmania of energy market
0.55%
0.17%
0.3%
0.18%
1.48%
0.86%
0.48%
0.05%
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.
