In a diverse region such as Europe, political differences constantly rear their head.
For the first time, however, they have started to impact the functioning of the electricity system at the highest, transmission level, with repercussions that work all the way down to the end users.
The issue appears to have its origins in the long-running feud between Kosovo and Serbia and the refusal of Serbia to recognise the independence of its former breakaway state.
In mid-January, Kosovo started to fail to meet its demand obligation and began drawing on external supply. Serbia, as leader of the Serbia, Macedonia, Montenegro (SMM) control area, likewise failed to meet its balancing obligation.
The outcome of this imbalance was a reduction in the grid frequency, to an average 49.996Hz from the standard 50Hz, according to the transmission system operator (TSO) organisation ENTSO-E.
While within the range for the functioning of the electricity system – 47.6Hz to 52.4Hz – nevertheless, there were impacts. Up to the first week of March when the situation was resolved and the frequency deviations ceased, the supply deficit in continental Europe was 113GWh, says ENTSO-E.
For consumers, the impact was a slowing of digital clocks that are grid frequency regulated by up to six minutes, e.g. electric alarm clocks, microwaves or oven clocks. Quartz crystal-based clocks were unaffected.
The area impacted, the Continental Europe synchronous area, covers 26 countries in mainland Europe. It excludes the UK and Scandinavia but includes the SMM control area, although not (yet) part of the European Union.
Tariffs and balancing
At the electricity sector level, the issue appears to revolve around responsibilities and breaches thereof. In a March 2018 statement Serbia’s system operator EMS blames its Kosovo counterpart KOSTT for “continuous deviation from the control programme” by “uninterruptedly withdrawing, in an unauthorised manner, uncontracted electricity” from the synchronous area.
“KOSTT has been, with such behaviour, violating norms and standards of the operational work in the Continental Europe synchronous area, and has also been in breach of its obligation of independently performing the control of its subarea within EMS’s control area,” says the statement.
For its part, KOSTT blames EMS for preventing it to act independently by obstructing the implementation of its October 2015 connection agreement with ENTSO-E, despite EMS being a signatory.
In its statement, KOSTT says that as a consequence its financial sustainability is being undermined. Until the agreement comes into force KOSST operates as an integral part of EMS, hindering its ability to set appropriate tariffs to recover losses. EMS also is retaining income from the allocation of capacities of Kosovo's interconnectors with neighbouring countries – for 2017 an amount “illegally collected” of €9.6m.
According to the statement, financial support from the Kosovo government enabled the interruption of the frequency deviations.
Normalising Continental Europe’s power system
While the impact of this event was not as serious as it could have been, it was unprecedented and highlights the challenges of an increasingly interconnected world when disagreements surface or indeed if a hacker were able to breach a national grid.
With a political basis underlying it, clearly a political solution is an important component, not least to avoid a recurrence. There is also the matter of the missing energy and how that might be recovered as the second step – after achieving the balancing of the SMM block – in fully resolving the issue.
ENTSO-E has urged European and national governments and policymakers to take swift action. The organisation is also trying to identify, in close interaction with the European Commission, a sustainable long-term solution that will avoid the situation happening again.
“This issue around Serbia and Kosovo shows again the complexity of ensuring the well-functioning of a power system,” comments ENTSO-E Secretary General Laurent Schmitt. “This complexity is set to increase as we are going towards a system of systems. The orchestration of the interactions between the different layers – nanogrids, microgrids, regional, national, pan European – is the fundamental challenge. This is where digital – and cybersecurity – come into place.”
Ultimately TSOs have the responsibility to respect their operational rules and standards. Their role is becoming increasingly complex in an environment increasingly reliant on a real-time response. The transmission grid, especially that of one of the world’s largest synchronous areas, is no place to air political differences.