System Prices Analysis Report: September 2021
This report covers the month of September. The System Prices Analysis Report (SPAR) provides a monthly update on price calculations. It is published by the ELEXON Market Operations on the Elexon Website and issued to the Imbalance Settlement Group (ISG) at their monthly meeting. This report provides data and analysis specific to System Prices and the Balancing Mechanism. It demonstrates the data used to derive the prices. The data is a combination of II and SF Settlement Runs.
Highlights from the September 2021 report
- On 9 September during Settlement Periods 33 and 34, the highest System Price (£4,037.80/MWh) since a single System Price was implemented as part of BSC Modification P305 on 5 November 2015 occurred.
- The monthly average Market Index Price, short System Price and long System Price were the highest on record.
- The two largest daily amounts were spent on 9 and 10 September; £1,572,336 and £1,589,690 respectively.
System Prices and length
This report covers the month of September. Where available, data uses the latest Settlement Run (in most cases ‘II’ or ‘SF’). In this report, we distinguish between a ‘long’ and a ‘short’ market when analysing System Prices, because the price calculation differs between the two scenarios.
When the market is long, System Prices are based predominantly on the System Operator’s ‘sell’ actions such as accepted Bids. When the market is short, System Prices are based predominantly on the System Operator’s ‘buy’ actions.
System Price summary by month (£/MWh)
This table gives a summary of System Prices for September, with values shown in £/MWh.
| System Length | Min | Max | Median | Mean | Std.Dev |
|---|---|---|---|---|---|
| Long | -66.73 | 200.00 | 96.40 | 93.91 | 21.33 |
| Short | 110.00 | 4,037.80 | 189.94 | 277.29 | 467.07 |
Source: Elexon
Frequency of System Prices over last month
This graph shows the distribution of System Prices across Settlement Periods in September 2021 when the market was long and short. 80% of System Prices were between £80.40/MWh and £238.89/MWh regardless of system length. When the system was long, 80% of prices were between £77.23/MWh and £110.00/MWh. When the system was short, 80% of prices were between £140.72/MWh and £287.00/MWh.
System Prices were £100.00/MWh or more on 940 occasions and £150.00/MWh or more on 545 occasions in September 2021. In the previous month there were 945 System Prices on or over £100.00/MWh and 189 System Prices on or over £150.00/MWh. The highest System Price of the month, £4,037.80/MWh, occurred in Settlement Periods 33 and 34 on 9 September. The prices in both Settlement Periods were set by an Offer from a Wind powered BM Unit priced at £3,999.00/MWh with a Buy Price Price Adjuster of £38.80/MWh applied. This was the highest System Price since a single System Price was implemented as part of BSC Modification P305 on 5 November 2015.