Southeast Europe is entering a decisive phase of battery energy storage deployment. Serbia, Romania, Bulgaria, Croatia, Montenegro, North Macedonia and Bosnia and Herzegovina are all accelerating renewable-energy investment while transmission system operators prepare their networks for rising shares of variable generation. As battery projects move from concept to construction, procurement strategy is becoming just as important as technology selection.
Across the region, battery tenders are still frequently evaluated using a familiar benchmark: capital cost expressed in €/kWh. While useful as an initial comparison, this metric provides only a partial picture of a battery project’s long-term value. For investors financing assets expected to operate for 15 to 20 years, procurement decisions based primarily on purchase price can introduce technical, operational and financial risks that may remain hidden until commissioning or commercial operation.
For Southeast Europe, where many utility-scale battery projects represent first-generation investments, procurement should increasingly follow an Owner’s Engineer (OE) and Front-End Engineering Design (FEED) methodology rather than a conventional equipment-purchasing exercise.
A battery energy storage system is not simply a collection of battery containers. It is a fully integrated power system combining battery cells, inverters, transformers, medium-voltage equipment, protection systems, SCADA, EMS interfaces, communication networks, fire protection, thermal management and civil infrastructure. Every subsystem can influence reliability, availability and the project’s long-term economics.
The role of FEED is to define these engineering requirements before procurement begins. Instead of asking suppliers to compete primarily on equipment price, developers establish a comprehensive technical specification covering operational objectives, grid-code compliance, environmental conditions, cybersecurity requirements, communications architecture, maintainability and long-term performance.
This approach is particularly important across Southeast Europe because transmission systems are evolving rapidly. National TSOs, including EMS in Serbia, Transelectrica in Romania, ESO in North Macedonia, CGES in Montenegro, NOS BiH in Bosnia and Herzegovina and ESO EAD in Bulgaria, each have specific connection requirements, protection philosophies and operational procedures. A battery selected without properly considering these requirements may require expensive redesign during detailed engineering or commissioning.
The Owner’s Engineer acts as the investor’s independent technical representative throughout the process. Rather than relying exclusively on EPC contractors or equipment manufacturers, the OE evaluates whether proposed solutions genuinely meet project objectives while protecting the long-term value of the asset.
This work begins during FEED through site investigations, grid studies, connection strategy, technology selection, energy modelling and the preparation of technical specifications. During procurement, the OE develops evaluation criteria that extend beyond €/kWh and include battery-degradation characteristics, round-trip efficiency, warranty provisions, auxiliary power consumption, thermal performance, availability guarantees, software capabilities and expected lifetime energy throughput.
Supplier evaluation also becomes more rigorous. Instead of automatically selecting the lowest bidder, the engineering assessment considers proven operational references, manufacturing quality, integration capability, commissioning methodology, spare-parts strategy, cybersecurity compliance, software support, warranty bankability and long-term service arrangements.
For lenders and institutional investors, these engineering considerations translate directly into project finance. A battery project financed on a project-finance basis depends on predictable cash generation rather than low procurement cost. Revenue assumptions rely on high system availability, accurate state-of-charge management, reliable control systems and effective participation in balancing, ancillary-service and energy markets.
An Owner’s Engineer therefore reviews the technical assumptions underpinning financial models. Expected degradation curves, replacement strategies, maintenance schedules, performance guarantees and warranty mechanisms can all influence long-term cash-flow projections and debt-service capacity.
The commissioning phase presents another area where independent engineering oversight can deliver significant value. Many battery projects achieve mechanical completion but then encounter delays during grid integration, protection testing, EMS communication, SCADA integration or performance verification. Such delays postpone commercial operation and can materially reduce expected returns.
Independent commissioning supervision helps ensure that factory acceptance testing, site acceptance testing, grid-code compliance testing, protection coordination, control-logic verification and performance testing are completed in accordance with contractual requirements before final acceptance.
Operational readiness is equally important. Successful battery projects require comprehensive operational documentation, maintenance procedures, spare-parts management, cybersecurity protocols, emergency-response planning, operator training and digital asset-management systems. These elements are rarely reflected in €/kWh calculations, but they can have a substantial impact on operational reliability over the asset’s lifetime.
The changing dynamics of Southeast European electricity markets further reinforce this engineering-led procurement philosophy. The expansion of renewable generation is increasing price volatility, creating more frequent negative-price events and expanding demand for balancing services. Batteries will increasingly derive revenue from multiple markets simultaneously, making software integration, response speed and operational flexibility as important as battery chemistry itself.
This is particularly relevant as countries across the region continue integrating with European electricity markets. Cross-border balancing, market coupling and expanding ancillary-service opportunities will increasingly reward battery systems capable of operating reliably under more complex market conditions.
Consequently, procurement should evolve from a hardware-acquisition process into an integrated engineering exercise combining FEED, Owner’s Engineer oversight, lifecycle-cost analysis and operational-readiness planning.
The most successful battery investments in Southeast Europe are unlikely to be those with the lowest procurement price. They will be projects whose engineering has been optimised before tendering, whose technical risks have been independently assessed throughout procurement and construction, and whose operational performance supports stable revenues over two decades of market participation.
As battery deployment accelerates across the region, €/kWh should become only one procurement parameter—not the procurement strategy itself. For developers, lenders and infrastructure investors, the real benchmark is no longer simply the cost of the battery, but the quality of the engineering that enables the system to perform safely, reliably and profitably throughout its entire operating life.
Elevated by Energy.Clarion.Engineer
