On December 24, at 3:51 p.m., the wind did what the market and the grid cannot always do: it kept Romania in the black. Wind energy covered about 2,400 MW, or about 30% of total production (almost 8,000 MW), and for several hours it was the largest single source in the national mix. At the same time, Romania exported electricity—a rather rare occurrence.
An analysis of Transelectrica’s data for the whole of 2025 shows that Romania was a net importer for approximately 72% of the time. In the data set analyzed (January 1–December 24, 2025), approximately three-quarters of the time shows consumption higher than domestic production, a difference covered by cross-border exchanges. On average, we needed about 444 MW to supplement from outside. Beyond the fact that we import frequently, it is worth noting that we import in a way that follows very clear patterns. Significant import episodes are not spread evenly throughout the calendar, but occur almost exclusively in the evening hours, when consumption rises rapidly and solar production disappears almost completely.
This is also where wind energy becomes crucial. In 2025, 47 of the 50 largest episodes of net imports occurred between 5 p.m. and 8 p.m. Basically, the evening peak is when Romania becomes vulnerable from this perspective. This is not surprising: it is the classic peak consumption window, especially in winter, when households and part of industry increase demand, and photovoltaics no longer help. What is less visible in the public debate is what is most often missing at these times. The pattern is simple and repeats frequently: during peak import hours, consumption is close to the peaks of the year, while wind production is usually at very low levels compared to its annual average.
It is easy to assume that large imports occur when “we do not produce enough,” but the data tells us more. At times of peak deficit, dispatchable power plants are usually already in demand. Gas production is high, coal is operating at high levels, nuclear is stable, and hydroelectric plants are used for balancing. However, the difference remains large enough to require consistent imports of sometimes close to 3,000 MW. These are the moments when consumption rises to its annual highs of nearly 9,000 MW and the wind is weak. It is not, therefore, a question of a general inability to produce energy, but rather a critical combination: very high consumption, no solar power, and weak winds, in a system where flexible resources are already in high demand. At such times, wind power is the missing factor that can reduce the need for imports.
I would like to point out that these observations are based strictly on Transelectrica’s public data on consumption and production by source and do not include market considerations such as prices, contracts, commercial strategies, reserved capacities, or network constraints. In practice, imports may also occur because energy from the regional market is cheaper, and cross-border exchanges are a normal tool in an integrated European system. In fact, overnight Romania’s consumption fell below 5,000 MW and it exported over 2,000 MW for several hours, while wind power alone consistently produced around 2,500 MW. Imports are not, by definition, a sign of weakness, and exports are not always a sign of strength for an economy. In many cases, cross-border exchanges are the result of price differences and they balance deficits in one country with surpluses in others. However, the data show that during critical evening hours, when consumption rises and the wind weakens, Romania becomes much more dependent on this interconnections safety net.
Throughout the year, wind power accounted for an average of approximately 11% of domestic production, compared to around 6% for photovoltaics – and the difference is most evident during the cold season and in the evening hours. At the same time, wind energy appears to be the most important variable in reducing the need for imports. The impact is clearer than that achieved by photovoltaics, because wind can deliver large volumes even in the cold season, and production can remain high even during critical evening hours, when the system needs it most. Hydroelectric and gas-fired power plants are essential for regulation, but they cannot change the rules of the game during peak hours on their own. When demand rises and variable sources are lacking, these plants are called upon to compensate, but they cannot always produce enough to completely eliminate the need for imports.
From this perspective, the photo from December 24 is more than just a nice image for the end of the year. It shows how high wind power production can reduce pressure on cross-border exchanges and give the system more space to breath. At a time when Romania is a net importer for most of the times, the contribution of wind power is not only proof of the green transition, but also a relevant element of energy security. This is all the more true given that, at critical times, the balance of the SEN depends on several variables that can change rapidly.
