BSC Operations Headline Reports

The report provides commentary on BSC market operation, identifying key events and reporting on important data that may impact BSC Parties. It is produced on a monthly basis and covers the data from the two previous months and is based on a combination of latest and best available data.

Latest report

Download the BSC Ops Headline Report (August – September 2019)

Content list

  • System prices in September 2019
  • Low carbon generation excceds 50% in September
  • Seasonal changes in offtaking TLMs

  • Balancing Mechanism Volumes in August
  • Trading Charges in August 2019

Feature articles

System prices in September 2019

Monthly average System Prices for September 2019 were lower when the market was both short (-1.8%) and long (-25.9%), compared to August 2019. The average System Price regardless of length was £32.08/MWh; 12% lower than last month and the lowest System Price since the May 2016.

System Prices did not exceed £100/MWh in September, compared to once in August. The highest System Price of the month, £100/MWh, occurred in Settlement Period 41 on 5 September and Settlement Period 27 on 30 September 2019. The price in both Settlement Periods was set by Offers from a Pumped Storage BMU, all priced at £100/MWh.

There were 24 negative System Prices in September, compared to 17 in August. This is the second highest number of monthly negative System Prices, following May 2019 (27), since the Single Imbalance Price was introduced on 5 November 2015. The lowest System Price, -£65.82/MWh, occurred in Settlement Period 45
on 2 September 2019. The price was set by three Bids from a single Wind BMU all priced at -£65.82/MWh.

Negative System Prices contributed to September 2019 having the lowest monthly average System Price since May 2016. Since the introduction of the Single Imbalance Price, 2019 has had the highest number of negative System Prices (96) and the lowest number of System Prices over £100/MWh (133) in the first three
quarters of the year.

Low carbon generation excceds 50% in September

In September 2019, Low Carbon generation exceeded 52% of total generation. This was driven by higher Wind
and Nuclear output, with Nuclear plants generating more electricity this month than in any month so far this year.

On 21 September 2019, Low Carbon generation contributed more than 70% of total generation. Whilst Interconnector volumes were lower compared to the average for September 2019 (7.6% vs. 8.6%), generation
from Fossil Fuel plants (mainly CCGTs) only accounted for 21% of total generation on this day. The percentage of Low Carbon generation was also likely to have been helped by the low demand seen on 21 September, as this was the second lowest in the month.

Seasonal changes in offtaking TLMs

This graph is an adaptation of “Daily Average Offtaking Transmission Loss Multiplier (TLM)” from the Trading Operations Report, with a number of GSP Groups removed. Following implementation of P350 ‘Introduction of a seasonal Zonal Transmission Losses scheme’ on 1 April 2018, TLMs vary by region and season.

The change in Transmission Loss Factors (TLF) on 1 September, due to the change in season from Summer to Autumn, has impacted TLMs in some regions more than others. North Scotland Offtaking saw the largest change. Average Offtaking TLMs were 0.991 during August, but decreased to 0.970 in September. South Scotland average Offtaking TLMs also decreased following the inclusion of the new seasonal TLFs, from 1.007 to 0.991.

The change in average Offtaking TLMs between August and September was less than 0.007 for
all other GSP Groups not featured in the graph. The drop in Offtaking TLMs seen on 16 September is due to the
change in Settlement Run data, as the run type moves from the Interim Information (II) to the Settlement Final (SF) Run. Historic TLM and Seasonal TLF data is available on the ELEXON Portal.

Balancing Mechanism Volumes in August

The total volume of balancing actions taken in the Balancing Mechanism (BM) for July 2019 was 1,717GWh, an 44% increase from August 2019. The majority (84%) of balancing volume in August came from Gas BMUs. The total volume of balancing actions was 61% higher than the same month in 2018.

Accepted Bid volume increased by 26% from July. 70% of total Bid volume came from Gas BMUs, with 16% coming from Wind and 8% from Pumped Storage BMUs.

Coal Bid volume in August decreased by 98% compared to July, whilst Bid volume from Biomass and Wind rose by 562% and 202% respectively. Accepted Offer volume in August increased by 63% from July 2019. Gas accounted for 95% of all Offer volume, with Pumped Storage responsible for a further 3%.

Coal Offer volume in August more than doubled since last month from 6,553MWh to 13,574MWh; however Coal still only accounted for 1.4% of total Offer volume.

Trading Charges in August 2019

Gross Party Imbalance cashflows were £74m in August 2019, a decrease of 10% from July. Credits for being short decreased by £3.9m, and credits for being long decreased by £4.6m, between July and August 2019.

Gross Party Imbalance Volumes increased by 11%. Energy Imbalance Volumes for Parties for that were long increased by just 14,158MWh (1.22%). Energy Imbalance Volumes for short Parties increased by 20%.

August Offer volume increase by 63% and Offer cashflow increased by 61%, compared to the previous month. The average price of Offers decreased by 1.4%, to £61.17/MWh.

Net Bid cashflow in August was £3.17m, compared to -£8.84 in July. This means payment received by Parties for negative Bids were higher what they paid for positive Bids. This is the first time the net
Bid cashflow has been positive since March 2019 (£17.02m)

Full list of reports

The BSC Operations Headline Report is produced on a monthly basis for the BSC Panel meetings, and is circulated to the Imbalance Settlement Group (ISG) as well as being published on the ELEXON website.

Please note that the reporting months are the two prior to the current month, based on a combination of latest and best available data.


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