Assessing hydrokinetic energy conversion for rivers across the world

Approximately one billion people worldwide lack access to electricity. Even more live in energy poverty while abundant, though unconverted, energy forms exist nearby. Hydrokinetic energy conversion offers the potential to alleviate some of this problem.

Ridgill et al. derived a novel methodology focusing on the transfer of kinetic energy through free-flowing river networks to determine areas suitable for the use of in-stream turbines.

“Hydrokinetic energy conversion is an immature renewable energy technology, and, although methodology for site-specific resource assessment exists, a general, global-scale perspective is lacking,” said author Michael Ridgill.

The authors used global-scale modeled river discharge data combined with a high-resolution vectorized representation of river networks to estimate channel form, flow velocities, and ultimately, global hydrokinetic potential.

Conventional hydropower often takes advantage of the gravitational potential energy resulting from large changes in elevation, such as mountainous areas and dams. However, the results indicated the lower courses of major rivers offer the most potential for hydrokinetic energy conversion.

“We highlight the fact that, though both renewable energy technologies make use of the same resource, they are different and the areas with the most potential for each are also different,” said Ridgill.

This new resource may prove impactful on the continents of South America, Asia, and Africa.

While large uncertainties are present in the proposed methodology, it offers a general perspective to describe where hydrokinetic energy may be harvested. Advancements in remote sensing and extraction of hydraulic geometry information may enhance this approach in the future.

Source: “Hydrokinetic energy conversion: A global riverine perspective,” by Michael Ridgill, Matt J. Lewis, Peter E. Robins, Sopan D. Patil, and Simon P. Neill, Journal of Renewable and Sustainable Energy (2022). The article can be accessed at https://doi.org/10.1063/5.0092215 .