A second, less visible investment cycle is beginning to take shape across Southeast Europe’s renewable sector. After more than a decade of initial wind deployment—particularly in Romania and Bulgaria—the region is now approaching a phase where early-generation assets are no longer optimally aligned with current technology, grid conditions or market dynamics.
The first wave of wind projects, developed primarily between 2008 and 2015, was built under different assumptions. Turbines in the 2–3 MW class, lower hub heights and less sophisticated control systems were sufficient in an environment characterised by feed-in tariffs and relatively stable generation profiles. Today, those same assets are operating in a fundamentally different system—one defined by price volatility, grid constraints and the need for flexibility.
Repowering offers a pathway to adapt these assets to current conditions. By replacing older turbines with modern units in the 5–7 MW range, developers can increase output by 30–60% without expanding site footprint or requiring entirely new permitting processes. This creates a compelling economic case, particularly in high-wind regions such as Dobrogea, where grid connections are already established.
The CAPEX profile of repowering is notably different from greenfield development. Typical costs range between €0.6–0.9 million per MW, compared to €1.2–1.5 million per MW for new projects, reflecting savings on land acquisition, permitting and grid infrastructure. Construction timelines are also shorter, often reduced by 30–40%, enabling faster return on capital.
However, the value of repowering extends beyond simple capacity increases. Modern turbines offer improved grid support capabilities, including advanced fault ride-through performance and reactive power control, making them better suited to increasingly constrained networks. This is particularly important in Southeast Europe, where grid stability is becoming a critical issue as renewable penetration rises.
The integration of battery storage into repowered assets is emerging as a key trend. By adding storage capacity—typically 20–50% of installed wind capacity—developers can transform legacy assets into flexible generation systems capable of participating in balancing markets and mitigating curtailment.
Romania is leading this transition. With more than 3 GW of installed wind capacity, much of it approaching or exceeding a decade of operation, the country represents the largest repowering opportunity in the region. Developers are actively assessing portfolios for upgrade potential, particularly where turbine performance has degraded or grid conditions have changed.
Bulgaria presents a similar, albeit smaller-scale opportunity, while Greece—despite having newer assets—is beginning to explore repowering in selected regions where grid constraints or land limitations make optimisation more attractive than expansion.
Serbia and Montenegro, with more recent wind deployments, are not yet at the repowering stage, but the concept is already influencing project design. New assets are being built with future optimisation in mind, including provisions for turbine upgrades and storage integration.
For investors, repowering offers a different risk-return profile compared to greenfield development. The presence of existing infrastructure reduces development risk, while increased output and improved efficiency enhance revenue potential. At the same time, regulatory uncertainty—particularly around permitting and grid access—remains a key consideration.
The emergence of this second investment cycle is significant for the broader renewable market. It introduces a new source of capacity growth that does not rely on new land or grid connections, potentially easing some of the constraints facing the region.
More importantly, it reflects a shift in how renewable assets are viewed. Rather than static installations, they are becoming dynamic systems capable of adaptation and optimisation over time. In that context, repowering is not simply a technical upgrade—it is a strategic response to a changing energy landscape.
Elevated by virtu.energy