BackgroundIn the coming years, the increase of automation in electricity distribution grids, controlled by ICT, will bring major consequences to the cyber security posture of the grids. Automation plays an especially important role in load balancing of renewable energy where distributed generation is balanced to load in a way that the grid stability is ensured. Threats to the load balancing and the smart grid in general arise from the activities of misbehaving or rouge actors in combination with poor design, implementation, or configuration of the system that makes it vulnerable. It is urgent to conduct an in-depth analysis about the feasibility and imminency of these potential threats ahead of a cyber catastrophy. This paper presents a cyber security evaluation of the ICT part of the smart grid with a focus on load balancing of renewable energy.MethodThe work builds on a load balancing centered smart grid reference architecture model that is designed as part of the evaluation with the help of SCADA system and smart grid experts. The smart grid load balancing architecture represented by the model is then analyzed using a threat modelling approach that is encapsulated in a tool called securiCAD. Countermeasures are introduced in the model to measure how much each improve the cyber security of the smart grid.ResultsThe analysis shows that the main threat comes from the internet and is directly dependant on the level of internet access office users have coupled with their level of access on the OT zone. Supply chain attacks are also of great concern, i.e. the compromising of the software/hardware vendor with the objective of feeding rogue updates to assets, typically to install a backdoor. The general takeaway defense-wise is that it is of the utmost importance to increase efforts in securing the smart Grid in all the ways possible as they appear to be generally complementary.DiscussionThe obtained results raise concerns whether the architecture of the smart grid still remains satisfactory in today’s state of the cyberspace and the increased presence and sophistication of cyber threats. There are also concerns whether the proposed security measures, regardless of their evaluated effectiveness, are realistically implementable from both financial and practical point of view.ConclusionsThere is no silver bullet available to achieve full protection against cyber attacks. The smart grid remains a network of IT/OT machines with dataflows going between them. State-sponsored hackers given enough time and regardless of the defences in place will eventually make their way into a critical infrastructure such as the smart grid. While mitigations will not eliminate the threats, they will increase the cyber resilience of the infrastructure by increasing both its time frame and effectiveness. As such, in a time where usability, efficiency and practicality are at the front of every domain, innovations regarding these aspects should really be carried out with strong security in mind.