24.07.2026
In his personal blog, Serhiy Yermilov – Minister of Fuel and Energy of Ukraine in 2000–2001 and 2002–2004, former Head of the National Agency of Ukraine for Ensuring the Efficient Use of Energy Resources, Honored Power Engineer of Ukraine – continues the series of publications on the future architecture of the Ukrainian power system. The author consistently builds the concept of a transformational transition from a centralized model to a modern digital power system based on the principles of Smart Grid.
In the sixth part of the blog, Serhiy Yermilov presents a roadmap for the transformation of the Ukrainian power system until 2031. It outlines the key stages of the transition to a Smart Grid, explains why modernization must occur without losing controllability and system resilience, and identifies technologies that will become the basis of the digital energy of the future – from digital substations and Smart Metering to distributed intelligence, virtual power plants and cyber resilience.
System Transformation. Transition from an Architecture Model to a New State (roadmap)
For Ukraine, it is especially critical to transform the system correctly and without errors. We are not building a system “from scratch”. We must modernize a system that:
Therefore, the key principle of the roadmap: Evolution without loss of controllability and resilience.
Goal: transition from partial observability to full observability of the network.
Current state
Many DSO networks remain virtually “blind”:
First steps
Result: DSO starts to see the network in almost real time.
This stage is one of the riskiest.
What we have now: SCADA + RTU; serial protocols; DNP3; IEC 60870-5-101; IEC 60870-5-104; Modbus; TDM architectures.
Logic: RTU → SCADA → dispatcher
What we want to get: IEC 61850 Digital Substation Architecture
IED ↔ Process Bus ↔ Station Bus ↔ SCADA/EMS
Main risk: trying to make a revolutionary transition – turn off the old → turn on the new.
This is unacceptable for the power system. Therefore, the correct strategy is:
Stage 1. Hybrid environment.
Working in parallel: IEC 101; IEC 104; DNP3; Modbus; IEC 61850 via gateway solutions.
Stage 2. IEC 61850 on new substations.
All new construction: digital-by-default; process bus; GOOSE; MMS; sampled values.
Stage 3. Gradual migration of legacy objects.
Without loss of dispatch controllability.
Here, the importance of time is often underestimated.
In the old system, seconds were permissible.
In the new: PMU; DERMS; VPP; Flexibility Markets require microsecond accuracy.
Required: GPS timing; PTP IEEE 1588; synchronized measurements; wide area monitoring.
In fact, a new resource is emerging: a single system time.
In my opinion, this is one of the least discussed topics.
The future power system will be managed not by individual physical devices, but by logical resources.
For example:
1000 home batteries – one VPP resource.
100 industrial loads – one flexibility portfolio.
500 EV chargers – one managed resource.
This is true energy virtualization.
The most important transition.
It was: event → center → decision → team
It becomes: event → local decision
↓
coordination with the upper level
For example: the inverter regulates the voltage; BESS smoothes the local peak; the microgrid performs local balance; the DSO only coordinates.
Here, in my opinion, Ukraine must be ahead of many countries. Because we already have a unique experience of attacks on the energy sector. But this is where the greatest danger of convergence lies.
In the old system: SCADA – a closed network
In the new: SCADA – ADMS – DERMS – AMI – EV – VPP – Cloud
Therefore,Cybersecurity should not be a separate project, but a requirement for each stage.
Principles: Zero Trust; OT SOC; PKI; IEC 62351; Network Segmentation; Secure Remote Access; Security by Design.
Stage 1 (2026–2027):
Visibility: telemetry; digital substations; AMI; DER inventory.
Stage 2 (2027–2028):
Integration: ADMS; DERMS; IEC 61850; CIM; utility IP/MPLS.
Stage 3 (2028–2029):
Flexibility: aggregators; VPP; flexibility markets; active DSO.
Stage 4 (2029–2031):
Autonomous Smart Grid: distributed intelligence; automated balancing; microgrid orchestration; large-scale DER participation.
SCADA convergence should be one of the central principles of the entire program:
Modernization should not destroy the existing operational controllability of the power system. The transition from classic SCADA/RTU architectures to IEC 61850 digital substations and IP/MPLS communications should be carried out in stages through hybrid environments with guaranteed preservation of the functions of dispatching control, relay protection, emergency automation and cyber resilience at each stage of transformation.
Sergiy Yermilov – Minister of Fuel and Energy of Ukraine in 2000–2001 and 2002–2004, former Head of the National Agency of Ukraine for Ensuring the Efficient Use of Energy Resources, Honored Power Engineer of Ukraine
