Changes in ramping on HVDC links at go-live of flow-based capacity calculation methodology

The Nordic TSOs are working towards the go-live of the flow-based capacity calculation methodology (FB) in October 2024. Analysis have shown that the new flow patterns that arise in the electricity system with FB, create challenges for some of the older HVDC cables. A number of measures are being introduced in order to ensure secure operation of the interconnectors.

Before the introduction of the flow-based method, an external parallel operation (EPR) is carried out at the Nordic level. During EPR, we use actual trading bids and simulate trading results with the flow-based method and compare with actual trading results with the current method (NTC). For the HVDC cables Fenno-Skan and SwePol Link, analysis during EPR show that changes of the flow between market time units (ramping) will increase to a level that would be technically impossible.

Ramping to be introduced on Fenno-Skan

As one of the agreed mitigation measures, Svenska kraftnät and Fingrid have agreed to introduce ramping on Fenno-Skan. At FB go-live, 600 MW ramping will be introduced on Fenno-Skan.

Ramping to be changed on Swepol Link

Svenska kraftnät and the Polish TSO, PSE, have agreed to change the ramping on Swepol Link from 600 MW/h to 300 MW/h at go-live of flow-based capacity calculation in the Nordics.

Further changes in connection with 15 minutes MTU go-live

At go-live of 15 minute Market Time Unit (MTU) on the day-ahead market, ramping will not be allowed within the hour. This solution will be implemented in order to ensure secure operation of SwePol Link with both flow-based and 15 minute MTU on the day-ahead market. The solution means that ramping will be allowed only at the first quarter of the hour, and no ramping for the rest of the quarters within the hours. If the stress on Fenno-Skan and Konti-Skan reaches unacceptable levels after go-live of 15 minute MTU, the TSOs intend to use the ramping solution with ramping only in the first quarter of the hour as a measure to protect the interconnectors.

Both ramping restrictions will be introduced in the ongoing EPR

Both the ramping restriction of 600 MW/h on Fenno-Skan, and 300 MW/h on SwePol Link will be implemented in the ongoing external parallel run of Nordic flow-based capacity calculation methodology. The EPR will continue until the Nordic FB go-live in order to provide stakeholders with an opportunity to get acquainted with the results.

More information

In case of questions to Svenska kraftnät, please send an e-mail to kapacitetshantering@svk.se

More information on flow-based capacity calculation implementation is available in Swedish under Utveckling av kraftsystemet

For information in English on the Nordic project for implementation of flow-based capacity calculation, please visit the Nordic RCC website Opens in a new window

For information in English on the Nordic project for implementation of 15 minute MTU and implementation of a new Nordic Balancing Model, please visit the NMB website Opens in a new window

More information on 15 minute MTU and new balancing model is available in Swedish under Utveckling av kraftsystemet