A new international study finds that harnessing a small share of offshore solar and tidal energy could dramatically reduce global emissions and reshape the clean energy mix.
Offshore clean energy potential far exceeds global demand
Offshore clean energy holds a production potential twice as large as current global electricity demand. Yet today, its contribution remains limited, largely concentrated in European offshore wind farms.
One of the main barriers to wider deployment lies in how resource potential has traditionally been assessed. Previous evaluations were conducted at a global scale, making it difficult to determine which specific marine resource offers the greatest energy potential in a given location.
The first comprehensive database of marine renewables
To address this knowledge gap, researchers from the University of Strathclyde in the United Kingdom and the University of Maine in the United States carried out the first global inter-resource assessment of marine renewables.
The team compiled more than 600 sector analyses and studies into a single database, standardizing energy potential into one unit of measurement, kilowatts per square meter (kW/m²).
Their findings show that tidal energy and floating solar photovoltaics consistently deliver higher energy density than offshore wind and wave energy across all world regions. In particular, offshore floating solar proved to be more reliable and less variable compared to other marine resources.
Despite this potential, offshore solar and ocean currents rarely receive sustained research focus, which helps explain why they remain largely untapped today.
Tidal energy and offshore solar could triple global potential
According to the study, fully harnessing offshore solar and tidal energy could nearly triple or even quadruple the global clean offshore energy potential, generating enough electricity to power hundreds of millions of homes.
Even a modest deployment would have a measurable climate impact. The researchers estimate that using just 2% of the combined offshore solar and tidal resources could reduce global emissions by 0.299 gigatonnes of CO₂ per year, assuming emissions remain at 2019 levels.
“At this rate, net zero would be achieved in 68 years,” the Scottish university states.
The research has been published in Renewable and Sustainable Energy Reviews.
