Serbia’s re-emerging interest in nuclear energy has shifted from a political signal into a structural policy debate, with the Serbian Academy of Sciences and Arts (SANU) now stepping in to question the economic and institutional logic behind deploying small modular reactors (SMRs). What might have initially appeared as a forward-looking diversification strategy is increasingly being reframed as a high-risk allocation of capital and regulatory capacity in a system that is already under pressure to modernise.
At the centre of the disagreement lies a fundamental mismatch between ambition and infrastructure. Serbia today operates a power system dominated by legacy lignite assets under Elektroprivreda Srbije (EPS), with thermal capacity still accounting for roughly 65–70% of generation, complemented by hydropower and a rapidly growing but still secondary renewable segment. The country has no operating nuclear facilities, no independent nuclear regulator with full operational capacity, no fuel-cycle infrastructure, and no long-term waste management solution. Against that baseline, the introduction of SMRs is not an incremental upgrade. It is a systemic leap.
SANU’s Energy Committee has framed this leap in stark terms. Its assessment suggests that SMRs, despite their branding as flexible and modular, remain commercially unproven in large-scale civilian deployment, with cost structures that remain opaque and, in many cases, higher than conventional alternatives. The critique is not limited to capital expenditure alone. It extends into lifecycle economics, where smaller units tend to lose the scale efficiencies that underpin traditional nuclear economics.
Globally, SMR capital costs are still being established, but current indicative ranges suggest €4,000–€8,000 per kW installed, depending on design and localisation. For a hypothetical 300 MW SMR unit, this translates into €1.2–2.4 billion per reactor, excluding financing costs, regulatory build-out, grid integration and waste management infrastructure. In a Serbian context, where total annual energy-sector investment has historically fluctuated in the €1–2 billion range, a single SMR project would absorb a disproportionate share of national capital allocation.
That imbalance becomes even more pronounced when financing structures are considered. Nuclear projects, including SMRs, require long-duration, low-cost capital, typically backed by sovereign guarantees or regulated asset base models. Serbia’s sovereign borrowing costs, while improved in recent years, still reflect emerging-market risk premiums. Eurobond yields have traded in the 5–7% range, significantly above the financing assumptions underpinning nuclear projects in Western Europe. The result is a direct escalation in levelised cost of electricity, pushing nuclear generation into a range that is difficult to reconcile with domestic tariff structures.
SANU’s intervention also highlights a less visible but equally consequential dimension: institutional capacity. Building a nuclear programme is not a construction project. It is a multi-decade institutional commitment involving regulatory oversight, safety culture, training pipelines and international compliance frameworks. Even SMRs, often presented as simplified systems, require the same foundational architecture as large reactors. The International Atomic Energy Agency (IAEA) has consistently emphasised that newcomer countries must establish full-scope regulatory and safety frameworks before deployment, a process that typically spans 10–15 years.
In that light, Serbia’s nuclear ambitions intersect with a timeline mismatch. The country’s immediate challenge is not long-term baseload scarcity but medium-term system balancing. As renewable capacity expands—particularly solar projects with capacity factors of 15–20% and wind projects reaching 30–40%—the grid increasingly requires flexibility, storage and dispatch optimisation. The key constraint is not the absence of generation capacity per se, but the lack of system flexibility to manage variability.
This is where the opportunity cost of nuclear investment becomes more tangible. A €2 billion allocation into SMRs could alternatively finance a diversified portfolio of assets delivering immediate system benefits. Utility-scale solar in Serbia is currently being developed at €600,000–€900,000 per MW, while onshore wind ranges between €1.2–1.6 million per MW. Battery energy storage systems (BESS), increasingly critical for balancing, are entering the market at €400,000–€700,000 per MWh installed, depending on configuration and duration.
In practical terms, the capital required for a single SMR could fund a portfolio equivalent to 1,500–2,000 MW of solar, 500–800 MW of wind, and 500–1,000 MWh of storage, fundamentally reshaping Serbia’s generation mix within a 3–5 year execution window. These assets also align more directly with EU financing frameworks, including EIB, EBRD and IPA III funding, where renewable and grid-modernisation projects benefit from concessional financing and grant components that significantly reduce cost of capital.
SANU’s argument on waste management further complicates the nuclear proposition. Serbia would not only need to build reactors but also establish a long-term strategy for spent fuel and radioactive waste. This includes interim storage, transportation, and eventual disposal, all under strict international oversight. For countries with established nuclear fleets, these systems have evolved over decades. For Serbia, they would need to be created from the ground up, adding both financial and political complexity.
The geopolitical dimension is equally relevant. Nuclear technology is not a neutral commodity. It is tied to supply chains, fuel provision, maintenance contracts and long-term strategic partnerships. Whether sourced from Western vendors, Korean consortia or other providers, each pathway introduces dependencies that extend well beyond energy policy into foreign policy alignment. In contrast, renewable energy supply chains—while not entirely free of geopolitical exposure—offer a broader and more diversified vendor landscape.
Yet the political logic behind Serbia’s nuclear interest remains understandable. Electricity demand is expected to rise as industrial activity expands, particularly in sectors exposed to CBAM-related decarbonisation pressures. Large consumers, including copper production in Bor, steel manufacturing in Smederevo and chemical processing clusters, will require stable, low-carbon electricity to maintain export competitiveness. Nuclear power, in theory, offers precisely that: firm, low-carbon baseload capacity.
The challenge is timing. SMRs are unlikely to deliver commercial electricity in Serbia before the mid-2030s at the earliest, given the lead time required for regulatory development, site selection, licensing and construction. By contrast, Serbia’s decarbonisation pressures—both from EU policy alignment and industrial competitiveness—are already materialising in the 2026–2030 window.
This creates a structural gap between the technology under consideration and the problem it is meant to solve. SANU’s critique effectively argues that Serbia risks investing in a long-term solution that does not address its immediate system needs, while diverting capital from technologies that can.
From an investor perspective, the contrast is even sharper. Renewable projects in Serbia are increasingly structured around long-term power purchase agreements (PPAs) with industrial offtakers, creating bankable revenue streams that support project financing. The emergence of CBAM-exposed industries as creditworthy offtakers strengthens this model, enabling higher leverage and lower cost of capital. Nuclear projects, by comparison, would require state-backed revenue frameworks, exposing public finances to long-term liabilities.
There is also a question of grid integration. Serbia’s transmission system, operated by EMS (Elektromreža Srbije), is already undergoing upgrades to accommodate increased cross-border flows and renewable integration. Large nuclear units, even modular ones, introduce concentrated generation nodes that require robust grid reinforcement. In contrast, distributed renewable assets can be integrated more incrementally, aligning investment with grid expansion.
None of this eliminates nuclear energy from Serbia’s strategic horizon. What SANU’s intervention does is shift the discussion from inevitability to sequencing. Nuclear power may still emerge as a long-term component of Serbia’s energy mix, particularly if SMR technologies achieve cost reductions and commercial maturity over the next decade. But the current question is not whether Serbia should ever build nuclear capacity. It is whether now is the right moment to commit to a pathway that demands substantial capital, institutional transformation and long-term risk absorption.
As the debate evolves, it is becoming less about technology preference and more about capital efficiency. Serbia is entering a phase where every major energy investment carries system-wide implications, from grid stability to industrial competitiveness and sovereign balance sheet exposure. SANU’s position introduces a disciplined counterweight to political momentum, insisting that energy policy must remain anchored in economic realism and institutional readiness.
The outcome of this debate will shape not only Serbia’s generation mix but also its broader economic trajectory. In a region where energy systems are being rapidly reconfigured under the dual pressures of decarbonisation and industrial policy, the ability to allocate capital efficiently may prove as important as the technologies themselves.
