MADRID, June 24, 2026 - As the world races to decarbonise, the search for new frontiers in renewable energy has moved beyond land to the sea. Floating offshore photovoltaic technology-solar panels deployed on the ocean surface-is emerging as one of the most promising frontiers in the global energy transition. And Spain, with its abundant sunshine and extensive coastline, is poised to lead the way.
New research from the University of A Coruña (UDC) has delivered a landmark finding: Spain's coastline could accommodate between 4.45 GW and 6.48 GW of floating offshore solar capacity, depending on the maritime spatial planning criteria applied. At the upper end of that estimate, the capacity would be enough to supply up to 9% of the country's electricity demand-a significant contribution from a technology that, until recently, was barely on the industry's radar.
, the study represents the first systematic evaluation of Spain's offshore solar potential using the country's Maritime Spatial Planning Plans (POEM), approved under Royal Decree 150/2023. The researchers developed a spatially explicit methodology using the Merganser floating platform developed by Dutch company SolarDuck as a reference, assuming a unit capacity of 0.52 MW.
There were two scenarios examined in the analysis. Scenario 1 only looked at high-potential areas that had already been identified for offshore wind development, and this analysis concluded that those identified high-potential regions could potentially support up to 6.48 GW of floating solar energy. Scenario 2 took a broader view and looked at all those marine areas that could potentially support floating solar energy without including the protected marine areas (such as military or shipping areas), fishing grounds, marine biosphere reserves, energy infrastructure, or any other competing activities. As a result of looking at a significantly larger area, the estimated installable potential for Scenario 2 was actually lower than that of Scenario 1 and was only able to produce or install 4.45 GW of floating solar energy.
This counterintuitive result has an important lesson for the industry: a larger available area does not necessarily translate into greater installable capacity. Water depth was found to be a critical factor, as it determines the length of mooring systems and the spacing required between platforms. Many of the areas opened up in Scenario 2 are fragmented or located in deeper waters, making the deployment of large floating platforms more difficult. The findings highlight the importance of jointly considering technical and planning-based constraints when assessing offshore solar potential.
The geographical distribution of Spain's offshore solar potential is highly uneven. Under the scenario based on priority offshore wind areas, more than 90% of the estimated capacity is concentrated in two regions: the Strait of Gibraltar–Alboran Sea and the Canary Islands. Under broader restrictions, the Mediterranean also shows development potential.
This concentration is not coincidental. These areas benefit from some of the highest solar irradiation levels in Europe, combined with relatively shallow waters and existing maritime infrastructure. The Canary Islands, in particular, face high electricity costs due to their island grid isolation, making offshore solar an especially attractive solution for local energy security.
Although offshore solar power is still developing, it provides some substantial benefits compared to onshore solar power. Firstly, the availability of land for electricity generation continues to decline due to the increasing demand for agriculture, conservation and urbanisation as competing uses of land increase, whereas the ocean presents large undeveloped opportunities for generating electricity from solar systems.
Second, and perhaps more significantly, seawater provides a natural cooling effect that can improve photovoltaic performance. The study cites previous research indicating that this cooling effect can increase electricity generation by up to 10.2% compared with equivalent onshore installations. Some floating PV platforms have demonstrated higher energy yields than conventional systems, with payback periods ranging from 2.8 to seven years.
Third, offshore solar can complement offshore wind development. The two technologies have complementary generation profiles-wind tends to blow more at night and in winter, while solar peaks during the day and in summer. Hybrid offshore projects combining both could significantly improve grid stability and reduce the need for storage.
While the 6.48 GW figure represents potential, real projects are already moving forward. Spanish energy company Naturgy, through its Innovahub innovation platform, has partnered with domestic engineering firm BlueNewables to develop a 1 MW floating solar installation off Spain's Mediterranean coast. The project includes two 500 kW units of the PV-bos (PhotoVoltaic–Bluenewables Offshore Solutions) floating platform, designed for open-sea operation.
Construction of the first unit is taking place at the San Enrique shipyard in Vigo. In May 2026, the platform was successfully launched into the water, marking the first pre-commercial scale offshore floating solar installation in Spain. The platform will be towed to the Port of Valencia for anchoring, connection, and a real-world testing phase. The project aims to advance floating PV platforms manufactured through industrialised and modular processes suited for large-scale production, with the goal of reducing costs, shortening production times, and improving the competitiveness of offshore solar.
The economic case for offshore solar in Spain is strengthening. Research on floating offshore solar farms in the Levantine-Balearic region has examined key financial parameters including capital expenditure, operating expenditure, and levelised cost of energy. Mapping studies have found that southern nearshore areas in Spain and Portugal present some of the lowest LCOEs for floating PV in Europe, at approximately €250/MWh. The Iberian Peninsula more broadly shows LCOE values in the range of €340–380/MWh. As technology matures and deployment scales up, these costs are expected to decline further.
Spain's regulatory framework is also evolving to accommodate this emerging sector. Beyond the POEM maritime spatial planning framework established in 2023, Royal Decree 962/2024 now regulates the competitive tendering process for licensing offshore renewable energy facilities. While current maritime planning explicitly considers technologies such as offshore wind and wave energy, it does not yet designate specific areas for offshore photovoltaics. The study's methodology provides a framework to support the realistic large-scale deployment of this emerging technology as regulators catch up.
Although there is great potential, offshore renewable energy resources are dependent on resolving serious technical obstacles. These obstacles result from the offshore environment which consists of harsh conditions (saltwater corrosion, wave action, biofouling by marine organisms) not experienced by onshore energy installations. Additionally, the following issues will require consideration in developing economically feasible mooring systems that are robust enough to withstand storm conditions and be integrated with electrical grids from offshore locations into the onshore electrical grid: l) understanding the environmental impacts of offshore renewable energy systems on marine ecosystems; and 2) determining whether there will be competition for ocean space using locations that may otherwise be suitable for floating solar energy systems.
Spain's offshore solar potential is not an isolated story. The Mediterranean basin, with its high solar irradiation and densely populated coastlines, shares many of the characteristics that make Spain an ideal testbed. Italy, Greece, and other southern European nations are watching closely.
What the University of A Coruña's research has demonstrated is that offshore solar is no longer a theoretical concept. With 6.48 GW of potential capacity, Spain could harness the power of the sun on its own waters to meet nearly one-tenth of the nation's electricity needs. The technology is here; the regulatory framework is taking shape; the first projects are in the water. The question is no longer it can scale.
As one industry observer put it: the sun has always shone on Spain. Now, it may soon shine from its seas as well.
