The Western Link HVDC, aka “Western Bootstrap”, a 2,200MW, £1bn transmission cable was built to help the UK manage the changing nature of energy production. However, since commissioning commenced in December 2017, the cable has experienced its third unplanned outage, with the most recent issue occurring on 6 April.
The below graph shows the relationship between the balancing services use of system (BSUoS) charges and activity on the Western Bootstrap. It illustrates how the cable effectively reduced the cost of the BSUoS charges, however during these outages average BSUoS fees climbed to £5.3mn a day.
Lee Drummee Analyst at Cornwall Insight, said:
“The Western Link HVDC was designed to to help prevent transmission bottlenecks and increase flows into England and Wales by accommodating the increasingly high volume of power generated in Scotland from wind.
“Avoiding transmission constraints not only allows more significant volumes of renewable power to flow onto the Grid but also reduces the amount of money that National Grid has to pay to turn off wind farms in Scotland to keep the transmission system stable.
“When the cable has been available it has succeeded in reducing BSUoS costs and increasing wind’s share of the generation mix. However, reliability seems to be an issue with the cable tripping once again on 6 April.
“As such, we have not seen an extended period without interruption, and the full benefits of the Western Bootstrap have yet to be realised.”
