Ocean currents as a strategic renewable energy resource
Ocean currents represent a vast and largely untapped source of renewable energy. With oceans covering about 70% of the Earth’s surface, the kinetic energy carried by marine currents and waves could significantly reduce reliance on traditional energy sources amid growing global electricity demand.
Global energy consumption has steadily increased over recent decades, with an average annual growth rate of 2.4% between 2015 and 2019. Fossil fuels still dominate electricity generation, making it essential to expand the share of renewable sources to cut greenhouse gas emissions and reduce long-term dependency.
Marine renewables still lag behind wind and solar
Marine energy offers greater predictability and almost uninterrupted electricity generation compared to many other renewable technologies. This makes it particularly attractive for coastal regions and island states seeking stable, clean energy supplies.
Despite these advantages, marine renewables remain far less developed than wind and solar power. Most previous studies have focused only on estimating the theoretical potential of ocean currents, without providing a comprehensive global assessment based on real-world data.
Identifying the most suitable locations for sustainable projects based on ocean currents is therefore critical to accelerating deployment.
First global assessment of ocean currents energy
The study titled “Drifter-based global ocean current energy resource assessment,” conducted by the College of Engineering and Computer Science at Florida Atlantic University and published in Renewable Energy, presents the first global evaluation of energy potential from ocean currents using long-term observational data.
Researchers relied on data collected over more than 30 years by NOAA’s Global Drifter Program, which operates around 1,250 satellite-tracked buoys measuring ocean current speeds and positions.
For the study, scientists analyzed more than 43 million data points recorded between March 1988 and September 2021.
Where ocean currents show the highest power density
The findings indicate that waters off the east coast of Florida and South Africa are particularly well suited for electricity generation. These areas show power densities exceeding 2,500 watts per square meter, approximately 2.5 times higher than an excellent wind resource.
Moreover, the waters in these regions are relatively shallow, around 300 meters deep, making them technically suitable for deploying ocean current turbines.
Other promising regions include the southeastern coast of the United States from Florida to North Carolina, as well as the eastern and southeastern coasts of Africa, including Somalia, Kenya, Tanzania, South Africa and Madagascar. In these areas, power densities exceed 2,000 watts per square meter.
Where extraction becomes more complex
In contrast, regions such as the eastern Pacific, including Japan, Vietnam and the Philippines, northern South America including Brazil and French Guiana, and the east coast of Australia show lower power densities.
In some high-density areas like South Africa and Japan, energy extraction is more technically challenging. Although power density is high, water depths can exceed 1,000 meters and flow patterns are more complex.
Deploying turbines in such environments would require specialized technologies and advanced mooring systems to ensure stability and operational reliability, increasing installation and maintenance costs.
Integrating ocean currents with other renewables
Seasonal variations also play a significant role in energy availability. In some cases, peak ocean current energy aligns with periods of higher electricity demand linked to air conditioning use, potentially enhancing grid reliability.
Researchers emphasize the importance of accounting for these variables to ensure efficient integration of ocean currents energy with other renewable technologies, strengthening overall system resilience.