Battery energy storage systems in Ukraine: from theory to real projects

The market for battery energy storage systems (BESS) in Ukraine has moved out of the discussion phase and into real execution. Just a few years ago, energy storage was discussed mainly as a component of a future power system. That future has now arrived: BESS projects are being designed, financed, connected to the grid, commissioned, and operating across the country.

This is a fundamentally important shift. It means the conversation has moved from “why do we need storage?” to “how do we make such a project work in practice?”

During an industry discussion organised by the Solar Energy Association of Ukraine, Vitalii Nykolaienko, Managing Partner of VOLTAGE Group, shared practical experience from real BESS projects — either already delivered or in development. He spoke not about abstract market optimism, but about concrete engineering solutions, grid connection realities, procurement mistakes, execution strategies, and the economics of successful storage projects.

This article turns those insights into a practical guide for investors, developers, EPC contractors, industrial energy consumers, and anyone tracking the development of Ukraine’s energy storage market.

Why the BESS market in Ukraine is growing

The first thing to understand: the energy storage market in Ukraine is growing not because the technology became fashionable. It’s growing because economics, regulation, and the power system’s needs have finally converged.

According to Vitalii Nykolaienko, 2025 can already be considered a breakthrough year for Ukraine’s storage market. During this period, a significant number of BESS projects were integrated into the country’s power system. And importantly — they were built for different purposes. Some to provide ancillary services for the system operator, others for energy arbitrage, others as a complement to PV generation or for industrial self-consumption.

This is a strong signal. A real market doesn’t emerge when everyone discusses one ideal model. It emerges when several different use cases start working simultaneously.

Several factors enabled this. Component prices fell enough to make financial models more realistic. The regulatory environment began adapting to storage. Banks are now more willing to consider energy projects with storage components. And pressure on the power system in general has made flexibility, dispatchability, and resilience much more valuable.

This is what really matters. BESS in Ukraine isn’t just a technology trend. It’s a practical infrastructure tool.

An energy storage system isn’t a “battery in a box”

One of the strongest messages of the presentation: an energy storage system can’t be treated as just equipment.

This sounds obvious, but the market keeps proving the opposite — sometimes in almost comical ways. People still behave as if you can buy batteries, place them on site, and profitability will materialise out of the mist. Energy projects are rarely that hospitable.

BESS is a complete infrastructure system. It involves technical concept development, grid connection strategy, design, electrical integration, control systems, operational logic, protection schemes, commissioning, and long-term performance assumptions. The commercial value of a project depends not only on the battery itself, but on how the entire system is configured and connected.

That’s why practical experience matters decisively. A project may look great on paper and still fail economically — if the engineering logic is weak, the connection conditions were misjudged, or the delivery model was fragmented.

Real experience: what VOLTAGE Group is doing in Ukraine

Vitalii Nykolaienko presented several examples from VOLTAGE Group’s practice in the Ukrainian market — both standalone BESS projects and storage systems integrated with PV generation.

According to data presented during the discussion, the company has approximately 80 MW of standalone energy storage projects in operation — mainly with four-hour storage duration — and about 60 MW of projects integrated with PV installations. In practice, this means hundreds of megawatt-hours of storage capacity are already part of an active portfolio.

The scale is significant. It demonstrates that storage in Ukraine isn’t about pilot ideas or demonstration installations. It’s a serious commercial segment that is developing.

Two cases were particularly telling.

The first — a 20 MW / 40 MWh BESS project for providing ancillary services. The project was delivered for DTEK on exceptionally tight timelines: construction began in May, and by September the project had entered its final commissioning phase. For an infrastructure facility of this scale, this is an exceptionally compressed schedule.

The second — a 2 MW / 4 MWh storage project for MHP. This project was built for industrial self-consumption, not for participation in the ancillary services market. It was integrated with existing energy infrastructure that included PV generation and internal electrical networks. This is exactly where design logic starts to matter: using existing substations, internal networks, and the client’s energy architecture allowed capital expenditure to be reduced and overall project economics to be improved.

It’s a recurring lesson in storage delivery. The battery may be new, but the smartest design often starts with the infrastructure that’s already there.

The most common mistakes in BESS projects in Ukraine

One of the central themes of the presentation was the idea that “small mistakes” in storage projects have very large consequences.

Most of them arise not from incorrect battery chemistry or a missed line in the specification. They arise earlier — at the concept stage.

The first typical mistake — underestimating the importance of grid connection and external grid infrastructure. Many investors focus their attention mainly on core equipment, because that’s where the largest share of costs is visible. The battery system, inverters, and core components can make up the majority of the budget, while grid connection infrastructure looks like only a minor line item.

This creates a dangerous illusion. Developers start treating grid connection as a secondary matter — something that will “sort itself out later”. In practice, this is exactly where projects lose months, burn through additional capital, or stop altogether.

A BESS without a working connection route is like a Ferrari without a road. Excellent engineering, zero mobility.

The second typical mistake — buying equipment before the concept is properly defined. Vitalii Nykolaienko gave real examples where investors first bought inverters or large quantities of PV modules, and then tried to figure out how the system should be integrated at all. In some cases, the chosen equipment turned out to be unsuitable for the planned project configuration.

The lesson is simple: first the concept, then the integration logic, then procurement.

This sequence matters because BESS projects are systems projects. If you change the order, you don’t accelerate the process. You simply move the chaos to a more expensive stage.

Grid connection is a separate project

If there is one issue that repeatedly determines the success or failure of BESS projects in Ukraine — it’s grid connection.

VOLTAGE Group’s practical advice: treat grid connection as a complete, standalone project, not as a technical addition to the main scope of work.

Why is this so important? Because a storage system must be understood in two operating modes. During discharge, it behaves like a generation asset. During charging — like a consumer. This means the connection strategy, technical conditions, and allowable capacity must reflect both modes.

This is where weak planning can quietly destroy a business model. The connection point may look acceptable in generation mode but turn out to be far more complex in consumption mode. The project may require grid reinforcement, transformer replacement, or other changes that significantly affect the economics and timeline. If these problems emerge too late — the financial model no longer matches reality.

In practice this means: investors should ask not simply “can the project be connected”, but “how exactly can it be connected, under what grid conditions, in which operating modes, and with what costs at later stages”.

This is where experienced grid teams and EPC contractors become critical.

10 kV, 35 kV, or 110 kV: which connection is better

BESS developers often ask at what voltage level a project should be connected. The answer, as always in real infrastructure: it depends on circumstances — but not in the lazy sense.

From VOLTAGE Group’s practical perspective, connection at 35 kV often provides a strong balance between project cost and long-term operational logic. At the equipment level it’s usually more expensive than 10 kV, but the difference isn’t always material compared to the total project cost. At the same time, it can offer strategic advantages, especially if future tariff structures or grid charging rules become less favourable.

This matters because energy regulation has a habit of behaving like mountain weather: stable, until suddenly — not.

Connection at 110 kV may also be appropriate — particularly for large projects — but as a rule it involves more complex equipment, longer delivery lead times, higher capital expenditure, and a longer execution horizon.

So the practical answer isn’t simply about what connection is technically possible. It’s about the balance between capital expenditure, timelines, operational flexibility, and regulatory risks.

How to size BESS for arbitrage or ancillary services

BESS sizing is one of the most important commercial design decisions.

Vitalii Nykolaienko’s experience indicates: for energy arbitrage under current market conditions, a four-hour storage duration often proves to be the most rational configuration. In other words, a 1:4 power-to-energy ratio currently performs well in financial models.

Three hours may be too constrained, and five — excessive under current revenue assumptions. This isn’t a universal truth for all markets and all future years, but it’s a justified conclusion based on practical modelling of real conditions in the Ukrainian market.

For ancillary services, the picture is different. The payment model and use case can justify a shorter configuration — specifically a 1:2 ratio between power and energy.

This is fundamentally important for developers and investors. There is no single “best” BESS configuration in absolute terms. There is only the best configuration for a specific use case.

Integrating BESS with PV generation in Ukraine

Combining PV generation and energy storage is becoming increasingly important in Ukraine.

The reason is simple. When solar power plant generation peaks, market prices often weaken. This reduces the value of energy sold directly during the sunniest hours. By adding storage, the project can shift energy to higher-value hours and improve profitability.

From VOLTAGE Group’s market view, most serious new investment projects in photovoltaics are now being considered together with storage. Developers increasingly understand that the economics of a standalone solar power plant differ from the economics of PV generation combined with storage — particularly in volatile market conditions.

This doesn’t mean every PV project automatically needs a battery at any price. It means storage is becoming part of the basic commercial conversation.

How to improve BESS economics using existing infrastructure

One of the most practical insights from the discussion relates to the industrial project for MHP.

The concept worked because it effectively used existing infrastructure. Existing substations, medium-voltage networks, and internal consumption profiles made it possible to integrate PV generation and storage in a way that reduced capital expenditure and avoided unnecessary duplication.

This is worth emphasising, because too many project concepts begin “from scratch” — even when the client already has electrical infrastructure that could be used intelligently.

If an industrial facility already has substations, internal distribution, connected load, and room for operational flexibility — that architecture can become one of the project’s biggest commercial advantages.

In practice this means: one of the smartest ways to improve BESS economics isn’t always optimising the battery itself. Sometimes it’s optimising the context around it.

Why the EPC model matters for BESS project delivery

Another key topic — project fragmentation.

When one company designs, another supplies equipment, a third builds, and a fourth handles commissioning — technical responsibility becomes blurred. This is exactly where practical problems multiply: equipment interfaces become unclear, control systems don’t talk to each other, protection schemes contain errors, civil works don’t match the actual equipment dimensions. And suddenly the project team is gathering for a meeting to determine whose mistake is currently the most expensive.

This kind of “theatrical performance” damages execution, and even more — project bankability.

VOLTAGE Group’s argument isn’t that all parts of a project always have to be within a single direct commercial contract. In some cases, core equipment can be purchased directly by the investor. But technical integration, engineering logic, and scope coordination must remain under the leadership of an experienced EPC structure or technical contractor.

In other words: if contracts are split, responsibility isn’t.

Choosing suppliers and technology partners for BESS

According to the approach described by Vitalii Nykolaienko, VOLTAGE Group works with Tier 1 manufacturers and evaluates both product quality and technical support capabilities.

Among the suppliers mentioned — Huawei, Kstar, and Cubenergy. The logic is pragmatic: high-quality technical support, proven performance, acceptability for bank financing, and reliable integration capabilities matter no less than equipment price.

This is particularly important in Ukraine, where the market is developing rapidly and project execution conditions can be complex. A supplier that looks attractive only in a comparative tender table can become a problem if local support, commissioning competencies, or integration speed prove insufficient.

This is exactly the area where the cheapest option can become the most expensive one quite quickly.

BESS project timelines in Ukraine

Project timelines depend significantly on the project type.

If a BESS is being built for self-consumption within the client’s existing infrastructure and doesn’t require complex connection work through the DSO or TSO, the process can progress relatively quickly. In some cases, delivery takes only a few months — provided equipment is available and the concept is mature.

But if the project requires new external grid works, formal connection registration, substation equipment, or integration at a higher voltage level — the timeline becomes significantly longer. Projects connected through 35 kV or 110 kV infrastructure may require approximately a year or more.

Equipment lead times are also important. Medium- and high-voltage components currently often have considerably longer lead times than a few years ago. Add a shortage of qualified personnel, procedural delays, and the general load on the energy sector — and project delivery turns into a serious coordination challenge.

So the correct question isn’t “how quickly can a BESS be installed?”, but “how quickly can this specific project be fully developed, connected, equipped, commissioned, and brought into commercial operation?”

These are entirely different questions.

What’s ahead for Ukraine’s BESS market

Vitalii Nykolaienko’s medium-term outlook is optimistic. According to his assessment, Ukraine can realistically expect the development of around 2 GW of storage capacity in 2026–2027.

This assessment reflects active investor interest, real project pipelines, and the power system’s growing need for flexible assets. It also confirms something important about the current market: Ukrainian investors themselves are playing a key role in driving this segment forward.

At the same time, long-term scaling depends on broader structural factors. Regulatory predictability. Access to financing. Investor trust. The general business and legal environment.

Storage can solve many energy problems, but it can’t on its own solve the problem of inconsistent governance or investment uncertainty. No battery has yet been certified to store legal stability.

Investment risks and opportunities in Ukraine’s BESS market

One strategic part of the discussion touched on institutional trust and the investment climate.

The practical view was balanced. On the one hand, Ukrainian banks are increasingly open to financing energy projects, including those involving storage. On the other — greater international investment appetite still depends on broader trust in stable rules, the ability to enforce them, and predictability.

This isn’t a unique feature of the BESS market. It’s a broader market reality. But for storage projects, it’s felt acutely — because they depend heavily on long-term economic assumptions.

The more stable the rules — the easier it is to finance and scale storage. The less stable — the larger the buffers, discounts, or shorter horizons investors require.

That’s why practical execution experience matters so much. In uncertain markets, a proven ability to deliver results becomes a strategic asset in itself.

Energy storage in Ukraine is no longer a future idea. It’s a practical market segment shaped by engineering, economics, and delivery discipline.

That’s exactly what makes Vitalii Nykolaienko’s and VOLTAGE Group’s experience so valuable. It shows not only that BESS projects can be delivered in Ukraine, but how to approach them with the seriousness that real infrastructure demands.

FAQ

Editorial note: This partner article was prepared on the basis of an industry presentation and discussion featuring Vitalii Nykolaienko, Managing Partner of VOLTAGE Group, at an industry event focused on the practical delivery of energy storage systems in Ukraine. The material was adapted and structured by the editorial team for publication on the nech website.