Cyprus power grid exposed: PV communication failure and northern fault trigger August blackouts
"Cyprus grid operators were forced to execute emergency load-shedding last week after a critical communication failure abruptly disconnected 165 megawatts of solar generation data from the system. While these automatic power cuts successfully prevented a cascading blackout, the incident has exposed severe vulnerabilities in the island's rapid renewable integration, prompting urgent calls from energy experts for immediate infrastructure upgrades and a comprehensive investigation into grid readiness."
EU Directive 2019/790 Article 15 Attribution • Verified Energy Document
Cyprus experienced two significant disruptions to its electricity system last week, affecting thousands of consumers across the island. The first incident resulted in an hour-long outage on Friday morning, while a separate event caused a 20-minute power cut early Saturday.
Investigations indicate that the initial disruption on Friday was caused by a temporary communication failure between the Distribution Control Centre and numerous photovoltaic (PV) parks. The subsequent Saturday outage was triggered by a fault within the generation system located in the island's occupied areas. In both instances, the electricity system initiated automatic protective power cuts, known as load shedding, to prevent more widespread and severe blackouts.
Haris Zavallis, assistant director of the National Energy Control Centre of the Cyprus Transmission System Operator (TSOC), explained the system's response, stating that future energy storage systems are expected to provide additional reserves and help mitigate the impact of similar incidents. However, electrical engineer and energy consultant Christakis Hadjilaou offered a more critical perspective, warning that the Friday incident was a serious wake-up call, highlighting critical questions about the integration, management, and control of rapidly increasing photovoltaic penetration within Cyprus’s electricity system.
The more severe disruption on Friday at 10:40 AM stemmed from an issue where large photovoltaic parks ceased sending accurate production data to operators. This led to a sudden loss of 165 megawatts (MW) of generation. For Cyprus’s electricity system, this represents a substantial amount of power, exceeding the output of the largest conventional generating units currently in operation (around 120 MW). This immediate and large-scale drop forced the system to automatically disconnect approximately 140 MW of consumer load, roughly 14% of the demand at the time, across six stages to restore balance. This rapid response was essential as increasing conventional generation takes significantly longer than the few seconds available to prevent a cascading system failure. The precise cause of the initial communication failure remains under investigation, as preliminary checks by Cyta, the telecommunications provider, did not identify issues with its infrastructure. The inquiry now involves the entire data transmission chain, including the telecommunications provider, the Control Centre's installer, and other relevant partners.
The Saturday outage, unrelated to the previous event, originated from a fault in the generation system in the occupied areas. Due to the interconnected nature of the island’s electricity systems, which operate as a single synchronised entity, the fault immediately impacted the Republic of Cyprus. This led to automatic protection systems activating and disconnecting about 20 MW of consumer load in government-controlled areas to rebalance the grid. While such interconnections can result in outages from external faults, they are generally considered vital for overall system security and stability, offering greater resilience during severe disruptions.
Hadjilaou emphasized that these incidents are not merely isolated technical faults but expose deeper issues in prevention, operational readiness, institutional responsibility, and accountability. He questioned why a backup telecommunications connection was only being promoted after the event, and whether existing backup measures, if any, failed to operate. He called for a comprehensive investigation covering the entire chain of planning, licensing, control, and supervision, involving TSOC, the EAC Distribution System Operator, photovoltaic park operators, telecommunications providers, and the Cyprus Energy Regulatory Authority. He stressed the importance of making the findings public, providing specific answers on what occurred, which safeguards functioned, which failed, who was responsible, and what corrective measures will be implemented. Hadjilaou also urged an assessment of potential risks under different conditions, such as during spring or autumn with varying demand and generation mixes. He concluded that while Cyprus averted a worse outcome on August 21, the incident should be treated as a serious warning, not as reassurance.