- Installed battery storage capacity has grown by 589% between April 2025 and April 2026, increasing from 28 MW to 193 MW.
- Storage linked to self-consumption has surged by 119%, with the residential sector recording the greatest growth following the blackout.
- In 2025, 5,414 GWh of electricity generated from renewable sources was wasted due to grid saturation. This means wasting an amount of electricity greater than the annual electricity demand of Spanish regions such as Extremadura (4,982 GWh).
One year has passed since the blackout that left much of the Iberian Peninsula (Spain, Portugal and southern France) without power. April 28, 2025 marked a turning point for our electricity system, exposing vulnerabilities that needed to be corrected: failures linked to grid operation, voltage management and the system’s automatic response to disturbances. But it also provided valuable lessons. The most important one: the need to accelerate the energy transition while strengthening the resilience, robustness and stability of the entire system.
Faced with an unexpected event that shook the energy and political landscape, there were two possible paths: either return to the familiar past, revive fossil energy and embrace the anti-renewables narrative that some tried to promote, or reinforce decarbonisation and the deployment of clean energy. Despite the work that still remains to be done, Spain chose the second path.
The blackout has helped accelerate the deployment of batteries to provide greater security to the grid and, at the same time, strengthen the profitability of photovoltaic energy, just as we requested from Fundación Renovables days after the energy collapse. According to data from Red Eléctrica, installed battery capacity stood at 28 MW in April 2025. One year later, in April 2026, installed capacity reached 193 MW. In other words, year-on-year growth reached 589%.
Regarding self-consumption, demand for storage installations — the so-called behind-the-meter batteries — experienced a sharp increase of 119% in 2025, rising from 155 MWh to 339 MWh, according to data obtained through APPA Renovables.
Battery installations for self-consumption increased by 155% in the residential sector and by 95% in the commercial/industrial sector. Although the highest year-on-year growth was recorded in households, it is worth highlighting the significant change seen over a longer time horizon in the industrial sector, since in 2023 storage capacity linked to self-consumption in factories and businesses was non-existent, at 0 MWh.
The data confirms that, following the blackout, self-consumption is no longer viewed solely as a simple tool for efficiency or decarbonisation. It has also become a key instrument for managing energy risk. The broader picture shows that the combination of distributed generation and storage is now helping to reduce dependence on the market, while cushioning price volatility and guaranteeing operational continuity.
Other steps forward
The supervision and control of the electricity system has been another positive transformation achieved as a result of the blackout. Mechanisms and protocols have been established for all electricity sector stakeholders, with greater obligations regarding transparency and real-time data. For example, the inspection capacity of the National Commission on Markets and Competition (CNMC) has been reinforced, and operational procedures have been modified so that renewable plants can implement ramp-up and ramp-down systems to avoid cascading failures. In addition, renewables have started controlling voltage through grid forming, a long-standing demand from the renewable energy sector.
Regarding grids, the Ministry for Ecological Transition and the Demographic Challenge (MITECO) launched, months after the blackout, its initial proposal for the development of the electricity transmission grid for the 2025-2030 period. The new roadmap prioritises investments of nearly €13.6 billion to integrate renewable energy, improve interconnections and support industrial electrification. The plan aims to consolidate a decarbonised system with 81% renewables in the energy mix by 2030.
Some measures have also been adopted to promote the electrification of demand. The Royal Decree approved in November 2025, which reinstated the measures from the failed Royal Decree-Law 7/2025, encourages the connection of new economic activities to the grid, particularly industrial ones.
The regulation also establishes the expiry of grid access and connection rights for demand after five years from their allocation, in order to prevent hoarding and speculation. Another important measure is the shortening of response times for distribution companies when deploying grid extensions, for example for electric vehicle charging infrastructure.
The negative side
Despite all this, not every step taken over the past year has favoured the energy transition. Following the blackout, Red Eléctrica activated a reinforcement system designed to provide greater stability and security to the electricity grid. However, this mechanism relied on increased use of combined-cycle gas plants to generate electricity. Unfortunately, what began as an emergency measure has become the new normal.
Electricity generation from gas increased by 50% between May and December of last year. However, in recent weeks a significant reduction in balancing costs has started to become noticeable, due to the fact that more and more renewable plants are beginning to carry out voltage control tasks. In any case, the major electricity companies, owners of combined-cycle gas plants, have benefited from the reinforcement mechanism by burning more gas and therefore increasing their revenues. As expected, CO2 emissions from the electricity sector rose by 9% over the last year, representing 2,444,735 additional tonnes of CO2 equivalent compared to the previous year, as confirmed by the report published by the Sustainability Observatory.
The greater use of gas to secure the grid has had an impact on households, especially on regulated market (PVPC) electricity bills. Balancing costs have doubled: adjustment services rose from €0.017/kWh in February 2025 to €0.029/kWh in February 2026.
The blackout also revealed that our electricity system remains highly isolated from the rest of Europe. One year later, commercial exchange capacity with the European system still represents only 4% of Spain’s installed generation capacity, a figure below the minimum recommended by Brussels.
Therefore, strengthening interconnections with neighbouring systems is emerging as one of the most important investments that must be undertaken in the coming years to complete the major domestic investment effort already made.
In this regard, increasing interconnections with France is a priority. It should be noted that in 2025 construction began on the underground line of the submarine interconnection with France through the Bay of Biscay, a 400-kilometre interconnection that will increase exchange capacity from 2,800 MW to 5,000 MW.
Pending tasks
Reducing dependence on gas and accelerating electrification in key sectors such as mobility, industry and heating/cooling is a crucial and decisive step that Spain must take moving forward. Despite the deployment of renewables, more than 70% of the country’s total energy consumption still depends on fossil fuels. Gas and oil imports alone cost more than €51 billion last year.
The war in the Middle East has reinforced the role of renewables as a strategic alternative to reduce exposure to fossil fuels. But demand electrification must accelerate. The good news is that this massive electrification is more feasible than it may seem. With just three technologies that are already mature in Spain — renewables, electric vehicles and heat pumps — two thirds of fossil fuel consumption could be eliminated.
Although 2025 recorded positive figures for renewable electricity generation, it also exposed grid saturation problems that forced a significant portion of electricity generated from these technologies to be curtailed. On average, 3.11% of renewable electricity had to be curtailed because it could not be integrated into the grid, with periods such as July when renewable curtailments exceeded 10%. This is partly linked to the technical grid restrictions implemented after the blackout. In total, 5,414 GWh of renewable electricity were wasted. This amount exceeds the annual electricity demand of Spanish regions such as Extremadura (4,982 GWh), Navarra (4,873 GWh), Cantabria (3,896 GWh) or La Rioja (1,571 GWh).
The excessive level of curtailments reveals the need to further accelerate and expand storage deployment, especially hybrid storage systems, in order to ensure that all generated electricity can ultimately be consumed and help cover time periods when renewable generation declines. Although installed battery storage capacity has increased by more than 500% since the blackout, Spain remains at the bottom of the European ranking, far behind Germany, Italy and the United Kingdom, which already have several GW of installed storage capacity.
