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.

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Content list

  • Feature on Scottish Offtaking TLMS Less Than One
  • Feature on High GGCFS on Easter Monday
  • Feature on Metered Volumes Exceeding Demand Capacity
  • Feature on No Coal Generation for Five Days in April
  • Regular article on Energy Balancing Volumes
  • Regular article on Trading Charges
  • Regular article on System Prices for the month

Scottish Offtaking TLMS Less Than One

The average offtaking Transmission Loss Multipliers (TLMs) in April are 0.998 and 0.991 for South Scotland and North Scotland respectively.

Since the implementation of BSC Modification P350 on 1 April 2018, the Offtaking TLM has been less than one in 81% of Settlement Periods in South Scotland and all Settlement Periods in North Scotland.

This is due to the two Scottish regions having negative Transmission Loss Factors (TLFs).

Graph showing Scottish Offtaking TLMS Less Than One

A negative TLF means an increase in generation (or a decrease in consumption) increases the total losses. The majority of generation is in the north, whilst the majority of consumption is in the south, so the energy ‘flows’ from north to south to met demand.

In Scotland, a Generator is likely to be negatively impacted by P350, but a Supplier should benefit as the energy produced is consumed ‘locally’.

High GGCFs on Easter Monday

This graph is an adaptation of “Daily Average GSP Group Correction Factor (GGCF)” from the Trading Operations Report. GGCF values usually range between 0.9 and 1.1, while values outside of this range may indicate an issue with metered volumes. On Easter Monday (2 April 2018), the daily average GGCF across all GSP Groups was above the usual range at 1.29.

Graph showing High GGCFS on Easter Monday

Traditionally profiles for Non-Half Hourly customers are less accurate on Bank Holidays. A GGCF greater than 1 scales up applicable Suppliers’ volumes (mainly Non-Half Hourly) to match the GSP Group Take.

The average Noon Effective Temperature for this day was 6.12oC, which was 3.81oC lower than the 10-year average for this date. After investigation, ELEXON has found no issues with metered volumes, so believe this anomaly is due to 2 April 2018 being a bank holiday.

Metered Volumes Exceeding Demand Capacity

During March 2018, there have been 1,048 incidences of a BMUs maximum demand being greater than their declared Demand Capacity (DC), based on metered volume data from the SF run. In this period, 324 BMUs exceeded their DC by more than the permitted tolerances specified in the BSC. The relevant BSC Parties have been contacted and asked to re-declare their DC values.

This graph shows one BMU exceeding their DC by 561MWh, and ELEXON is currently investigating this anomaly.

Graph showing Metered Volumes Exceeding Demand Capacity

DC is used to calculate indebtedness in the Credit Cover Calculation where no metered data is available.

DC re-declarations can be made at anytime using the online forms held on the ELEXON Portal.

No Coal Generation for Five Days in April

Generation from Coal BMUs did not contribute to the GB fuel mix during five Settlement Days in April 2018. The longest continuous period without coal was three days, between Settlement Period 21 on 21 April and Settlement Period 28 on 24 April (152 Settlement Periods, or 76 hours).

The first day without Coal generation since the industrial revolution occurred a year earlier on 21 April 2017.

Graph showing No Coal Generation for Five Days in April

During April 2018, 41% of Settlement Periods had no generation from Coal BMUs. In comparison, in April 2017 19% of Settlement Periods had no Coal generation.

Coal generation accounted for 2% of the fuel mix in April 2018. The remaining fuel mix consisted of: Gas (45%), Nuclear (23%), Wind (14%), Interconnectors (8%), Biomass (6%), and Hydro/Pumped Storage (2%). During Settlement Periods without Coal generation, Wind generation accounted for 20% of the fuel mix.

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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