Serbia is entering the most decisive decade in the modern history of its energy system. What for years looked like a stable and predictable structure built around lignite baseload, large hydropower and modest imports is being replaced by a far more complex reality driven by renewables expansion, climate pressures, aging coal fleets, system reliability risks and rising demand. Policymakers, utilities, investors and international partners are today converging around one central strategic question: how much firm gas-fired capacity will Serbia really need by the mid-2030s and 2040 to keep the lights on, stabilise its grid and anchor the renewables transition?
This question is not academic. It determines upstream gas strategy and long-term contracts, shapes foreign policy choices, affects industrial competitiveness, influences Serbia’s relationship with EU policy frameworks, and guides capital allocation for the next fifteen years. It drives how much Serbia will rely on itself and how much on neighbours, how it navigates cost and climate responsibility, and whether consumers face structural risk or structural stability.
To answer it properly, baseload must be treated not as a number of plants, but as part of a full power-system logic. That means starting with demand, understanding the scale of renewables, estimating what can be relied upon in winter, and then calculating the firm capacity gap that must be covered by coal, gas, nuclear, storage, import contracts or some combination of all of them. When this is done rigorously, Serbia’s likely gas requirement narrows to a realistic corridor rather than speculation or political messaging.
Demand in 2040: Bigger system, higher winter risk
Serbia today consumes roughly 34–35 TWh of electricity annually. Even under conservative assumptions, economic growth, electrification of industry, transport and households, as well as structural integration with European markets, push that towards approximately 40–41 TWh by 2040. That equates to an average system load of around 4.6–4.7 GW, but what truly matters is winter peak and security margins.
With historical load factors and seasonal behaviour, winter peak demand by 2040 can realistically be expected in the range of 7.5–8 GW. For a safe power system, planning requires reserve margins; a system that must operate under regional stress, climate shocks, drought years and market volatility cannot plan to the bare minimum. Add a reasonable security margin and Serbia will require close to 9 GW of firm, dependable capacity in 2040.
That is the benchmark: a 9 GW firm capacity system requirement.
Renewables expansion changes energy balance – but not reliability logic
Serbia’s energy strategy envisions a massive transformation of the production mix. By 2040, variable renewables alone could exceed 10 GW of installed capacity, with roughly 3.5–4 GW of wind and more than 7 GW of solar. Hydropower remains critical, reinforced by new river hydropower plants and, more importantly, pumped-storage projects such as Bistrica and regional cooperation concepts like Đerdap 3.
In annual energy terms, this is transformative: renewables by 2040 are expected to generate roughly 70% or more of all electricity consumed in Serbia. The system fundamentally shifts from coal-dominated energy to renewable-dominated energy.
But capacity and energy are not the same. Serbia will indeed have more installed megawatts than ever before, but far fewer of them are guaranteed to be available exactly when needed. Firm capacity planning assigns conservative “capacity credit” to renewables: hydro is reliable but hydrology fluctuates, wind availability is uneven, and solar contributes little in dark winter evenings. When converted into firm, dependable winter power, this giant renewable fleet realistically contributes only around 4–4.5 GW of capacity Serbia can truly count on.
That leaves roughly 4.5–5 GW of firm capacity still needing to be covered, regardless of how impressive the renewable build-out becomes.
Coal in 2040: Still there, but in what condition?
The next critical variable is coal. Serbia’s lignite fleet is aging, technically challenging, increasingly expensive to maintain and politically constrained by climate commitments and European integration. Yet it remains deeply embedded in the energy system, employment structures and energy security reflexes.
Three pathways are realistic. In the most conservative scenario, Serbia continues to rely heavily on coal even in 2040, maintaining something like 3 GW of firm coal capacity through upgrades, selective retirement and the addition of new units such as Kostolac B3. In a mid-transition scenario, coal is still present but significantly reduced, providing perhaps 1.5–2 GW of dependable capacity. In a climate-aligned scenario, coal’s firm role is largely gone by 2040, replaced by lower-carbon or zero-carbon alternatives.
The political economy reality suggests Serbia will not eliminate coal quickly. Coal will exist in 2040. The true question is whether it remains the backbone or becomes a controlled, shrinking pillar that must be systematically backed by new technologies.
Gas as baseload: The backbone Serbia will realistically need
Once coal’s uncertain trajectory is superimposed against the firm capacity gap, Serbia’s need for gas becomes much clearer.
Under a conservative pathway where coal still reliably covers around 3 GW of firm needs in 2040, the gap for gas is surprisingly modest: around 1.5–2 GW. That translates into roughly three to four modern combined-cycle gas power plants capable of running at baseload but also flexible enough to balance variable renewables.
Under a faster coal phase-down scenario, where lignite plays a reduced but still meaningful role of around 1.5–2 GW, Serbia’s required gas capacity rises to 3–3.5 GW. That equates to around four to six major CCGT units, enough to underpin security but still leaving renewables as the dominant energy source.
In a climate-compatible pathway where coal is largely pushed to reserve status, Serbia technically needs around 4.5–5 GW of firm alternative capacity. If nuclear, hydrogen or very aggressive storage build-out do not materialise on time, the default technology that can realistically be built, financed, integrated and delivered remains gas. In that case, gas could become the new coal: the baseline of the system.
This highlights a crucial truth: Serbia’s gas requirements are not a function of ideology or external pressure. They are a simple function of physics, reliability and what Serbia chooses to do with its coal fleet.
Why gas matters even in a renewable-dominated system
Many policymakers and citizens assume renewables automatically eliminate the need for fossil fuels. In practice, even very green European systems retain firm thermal capacity because renewable output is weather-dependent, especially in winter. Serbia’s energy risks concentrate in cold, dark, windless periods, exactly when solar does not exist and wind cannot be guaranteed. Hydrology can fluctuate significantly as well.
Gas offers something Serbia’s system desperately needs: speed, flexibility, dispatch certainty and regional resilience. It can operate baseload, mid-merit or peaking, meaning it stabilises prices, reduces reliance on expensive imports during crises and prevents blackouts. In a grid with huge renewable penetration, firm gas becomes not a step backward, but the enabling layer that allows renewables to dominate safely.
There is also a geopolitical and systemic logic. Serbia imports power during winter stress. Regional power markets have begun to move synchronously under stress conditions, meaning neighbours face shortages and price spikes at the same time. Relying structurally on imports in such conditions is not energy policy – it is risk exposure.
The realistic planning corridor
By combining system modelling logic, policy direction, realistic infrastructure development pacing and risk tolerance, Serbia’s likely gas requirement narrows into a pragmatic planning corridor.
By 2035, Serbia will almost certainly require at least around 1 GW of new firm gas capacity simply to stabilise an increasingly renewable-heavy grid and compensate for aging coal reliability issues. This is likely the minimum politically and technically required.
By 2040, in a scenario consistent with Serbia’s current strategy and political trajectory, the country will likely need between 1.5 and 2 GW of domestic gas-fired firm capacity. This assumes coal is still meaningfully present, hydro continues to play a strong role and storage supports balancing.
If coal declines faster than currently envisioned – whether due to economics, EU pressures, aging failures or social consensus – then Serbia’s gas requirement approaches 3–3.5 GW. This is a serious build programme, but still compatible with a highly renewable system.
Only in fully climate-aligned or nuclear-heavy scenarios does gas either shrink dramatically or transform into low-carbon gas with CCS or hydrogen. Those pathways require decisions Serbia has not yet truly taken.
Investors’ and policymakers’ implications
For policymakers, the message is clear: gas is not a temporary distraction; it is structural infrastructure that must be planned decisively, not reactively. Serbia cannot afford to stumble into gas dependence through crisis purchases and emergency investments. It needs intentional, strategically located, efficiently sized CCGT capacity.
For investors, the logic is equally strong. Serbia presents a credible medium-term gas power investment landscape, anchored by strong renewables growth, regional grid relevance and secure demand for baseload and balancing. Gas projects will not compete with renewables; they will enable them. Financial structuring, regulatory clarity and long-term contracts will be key.
For regional and European partners, Serbia’s choices matter beyond its borders. A stable Serbian power system stabilises Southeast Europe. A weak one exports volatility.
A strategic decision Serbia cannot postpone
Serbia’s power sector is moving from certainty built on lignite to a system defined by renewable variability, winter risk and strategic vulnerability if the firm backbone is not replaced on time. Hydro and storage help. Renewables transform the energy share. But on their own they do not deliver security.
That is why the real question for 2035–2040 is not whether Serbia needs gas, but how much and how fast it should build. The answer, based on realistic scenario logic, is not infinite and not negligible. Serbia is likely heading toward three to six serious gas plants depending on coal trajectory, representing 1.5–3.5 GW of firm capacity that will secure industrial competitiveness, protect households and underpin the renewables transition.
This is not an argument for fossil fuel dependence. It is an argument for responsible energy transition. Serbia’s energy future will be renewable-rich. But to get there safely, without risking blackouts, import shock or systemic instability, the country will need a disciplined and strategic gas baseload core.
The window to decide is not 2040. It is now.
