In Southeast Europe (SEE), the economic viability of renewable energy generation and storage is increasingly tied to advancements in grid infrastructure. Recent analyses indicate that projects related to transmission upgrades, substations, and interconnectors are becoming essential for facilitating renewable integration and optimizing storage capabilities. As the energy landscape evolves, these projects are now recognized as pivotal elements in the region’s energy transition.
Montenegro exemplifies this trend with its national transmission system operator, CGES, announcing an ambitious investment exceeding EUR 200 million over the next five years. This initiative includes the construction of new 110 kV transmission lines, the establishment of a 400 kV Brezna substation, and a 400 kV interconnection with Serbia. These developments are strategically designed not only for reliability but also to support future capacities in solar, wind, hydro, and storage sectors.
The Brezna substation is particularly significant as it will serve as a cornerstone for new high-voltage corridors that will enhance renewable energy penetration. It is also expected to support a potential second submarine cable to Italy, aimed for completion after 2028. Without these essential grid reinforcements, Montenegro’s growing renewable capacity could encounter severe limitations, including curtailment and export challenges.
Further illustrating the necessity of robust infrastructure is the planned reconstruction of the Perućica hydropower plant substation. This project focuses on enhancing operational reliability and flexibility rather than increasing generation capacity. By modernizing existing control systems, Montenegro aims to improve its ability to manage hydro resources effectively while integrating variable renewable sources without compromising overall system stability.
The challenges faced by neighboring countries such as Hungary and Romania highlight similar dynamics within their grids, which are under pressure from cross-border flows and increasing solar saturation. These issues may not always be categorized as distinct projects but are evident in market reports through rising price spreads and congestion risks attributed to grid bottlenecks.
The interaction between grid assets and energy storage solutions plays a crucial role in this context. For instance, the Maritsa East 3 battery project in Bulgaria leverages its strategic grid position by utilizing connections from an existing coal unit. This approach minimizes the complexities associated with securing new grid access, underscoring how legacy connections can become valuable assets during the energy transition.
Interconnectors serve dual purposes by enhancing supply security while simultaneously increasing price correlation across markets. The forthcoming Montenegro–Serbia 400 kV link is expected to bolster regional balancing efforts and facilitate renewable exports; however, it may also amplify price volatility during periods of stress. This indicates that while grid expansion can mitigate some risks, it can also redistribute them across interconnected markets.
From an investment perspective, grid projects present a distinct risk-return profile compared to traditional generation assets. Typically characterized by regulated and stable revenues, these projects hold strategic importance due to their potential to unlock further private investments in renewables and storage solutions. Consequently, there is growing interest from institutional investors looking for stable exposure within the evolving energy landscape.
The emerging consensus is that grid infrastructure acts as a keystone project for the SEE energy transition. The successful integration of solar, wind, hydro, and battery technologies hinges on adequate transmission capacity and connection points. Markets that neglect grid modernization face increased curtailment risks and volatile pricing scenarios, while those prioritizing infrastructure improvements stand to fully realize the benefits of flexibility and decarbonization efforts.
