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

Headline report April-May 2019

Content list

  • Coal Makes Way For Renewables 
  • Highest embedded generation in 2019
  • System prices in May
  • Balancing mechanism volumes in April
  • Trading charges in April

Feature articles

Coal makes way for renewables

In May, Great Britain experienced the longest ever period without coal power generation, lasting 18 days and 6 hours (876 Settlement Periods). The record for the longest ‘coal-free’ period has been broken four times this year; twice in April and twice in May.

During the most recent period, GB generation consisted of CCGT (46%), Nuclear (21%), Wind (14%), Interconnectors (12%) and Biomass (9%).

In the absence of Coal-fired generation, renewable sources have
increasingly contributed towards the GB fuel mix. In the latest coal free record period, Biomass contributed on average 8% of generation, the highest on record. Biomass generation’s previous peak (in percentage terms) occurred in May last year.

As shown in the chart below, renewables fuels, such as Wind and Biomass, are increasing to offset the rapid decline in Coal generation. Up to the end of May 2019, renewables accounted for 24% of total generation, behind only CCGT (43%) and ahead of Nuclear (20%). 

(Generation data for this article is taken from the ELEXON Portal from the Historic Fuel webpage)

Highest embedded generation in 2019

Embedded generation is sourced from BM Units connected to the low voltage Distribution Network rather than the high voltage Transmission Network (like larger more traditional generators). Although the fuel type associated with embedded generation can vary, the majority comes from renewable sources.

Generation from these units has amounted to 989GWh from January to May 2019, more than any previous year for this period. Since 2016, embedded generation output has risen on average by 4% per year. The highest monthly output for the analysed period was seen in March 2019, where the generation for the month reached 228GWh.

There has been a consistent increase in the number of embedded BM Units registering to become a BSC Party since 2016. As at the end of May 2019, 235 embedded BM Units have been registered, 140 (147%) more than 2016. However, total generation from embedded BM Units has only risen 13% across the same period.

A large proportion of embedded generation plant is located in Scotland. Over the past 4 years, the two Scottish Grid Supply Point (GSP) groups have contributed an average of 27% of the total GB embedded generation. Generation data in this article is taken from the published data in the ELEXON Trading Operations Report.


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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