Spain Could Have Nearly 7 Gigawatts of Offshore Solar Power

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We’ve written for years about how much solar power potential countries have, how much onshore and offshore wind power potential countries have, and how much solar power growth is occurring in countries around the world — but what about offshore solar power potential? That was never really part of the equation. However, as floating solar PV has proven itself and grown to significant levels, some are having the sense to evaluate offshore solar power potential.

In one of the sunnier countries of Europe, Spain, researchers have tried to quantify how much solar PV power could be built offshore. (Admittedly, the country is probably not feeling very sunny or optimistic today, given that their team just tied Cape Verde 0–0 in the World Cup, but that’s another story.)

Researchers from the University of A Coruña determined that 4.45 GW to 6.48 GW of floating offshore solar PV power capacity could be developed off the coast of Spain. That much solar power capacity could provide the country with 6.2% to 9% of the country’s electricity demand based on September 2025 data.

The evaluation utilizes Spain’s Maritime Spatial Planning Plans (POEM), which came through Royal Decree 150/2023.

The full study, “Assessment of installable offshore solar power capacity in Spain based on maritime spatial planning,” was published in the Journal of Cleaner Production.

Note that aside from simply adding solar power potential, there are actual benefits to floating solar PV systems versus conventional land-based solar PV systems. The cooling effect of the water under and around the solar PV systems can boost electricity generation from the solar panels by 10.2%. Payback periods can range from about three to seven years.

What about offshore wind power? If you have offshore solar, you can’t have offshore wind, right? Actually, the researchers see them as being complementary rather than competing with each other. In fact, having both technologies in the water, they could share some electricity infrastructure and both could be more economical.

Featured image from SolarDuck.