Connect with us

Hi, what are you looking for?


Clean Power

New Renewable Electricity Source, River Mouths, Could Support Half a Billion People

The point where a river flows into the ocean, the river mouth, could generate enough electricity to support over half a billion people according to a new analysis.

The process by which a river flows into the ocean is known as pressure-retarded osmosis (PRO). It was examined for its power-generation potential by Ngai Yin Yip and Menachem Elimelech from the Department of Chemical and Environmental Engineering at Yale University in the most recent edition of the journal Environmental Science & Technology.

They note that enough electricity could be generated by tapping only one-tenth of the global potential of PRO, and that it would require no fuel to run, is sustainable, and would release no carbon dioxide. (Note: last year, Stanford researchers cam to a similar conclusion, finding that this renewable energy source could generate 13% of the world’s energy needs at that time.)

PRO exploits the difference in saltiness between the freshwater river and the saltwater ocean. According to the American Chemical Society, “in PRO, freshwater flows naturally by osmosis through a special membrane to dilute seawater on the other side. The pressure from the flow spins a turbine generator and produces electricity.”

Following the first prototype PRO plant being established in Norway in 2009, the researchers set out to better calculate the actual contribution to future energy needs under real-world conditions of a PRO system.

Yip and Elimelech conclude in their study that PRO power-generating stations which used only one-tenth of the global river water flow into oceans could generate enough electricity to meet the needs of 520 million people, and all without emitting any carbon dioxide. In comparison, the same amount of electricity generated by a coal-fired power plant would end up releasing over one billion metric tonnes of greenhouse gasses each year!


Source: American Chemical Society
Image Source: Randen Pederson

I don't like paywalls. You don't like paywalls. Who likes paywalls? Here at CleanTechnica, we implemented a limited paywall for a while, but it always felt wrong — and it was always tough to decide what we should put behind there. In theory, your most exclusive and best content goes behind a paywall. But then fewer people read it! We just don't like paywalls, and so we've decided to ditch ours. Unfortunately, the media business is still a tough, cut-throat business with tiny margins. It's a never-ending Olympic challenge to stay above water or even perhaps — gasp — grow. So ...
If you like what we do and want to support us, please chip in a bit monthly via PayPal or Patreon to help our team do what we do! Thank you!
Sign up for daily news updates from CleanTechnica on email. Or follow us on Google News!

Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.

Written By

I'm a Christian, a nerd, a geek, and I believe that we're pretty quickly directing planet-Earth into hell in a handbasket! I also write for Fantasy Book Review (, and can be found writing articles for a variety of other sites. Check me out at for more.


You May Also Like

Climate Change

There are currently seven recognized negative emissions technologies (NETs). What are their global CO₂ removal potential, costs, and relevant side effects? An overview of...


Carbon dioxide gets a workout in this new long duration energy storage system that can deliver wind or solar power 24/7.

Green Economy

Benjamin Schulz: When did you create Ebb Carbon, and what’s the story behind it? What was your initial motivation to create Ebb Carbon?  Ben...

Climate Change

SciTechDaily reported that there’s some new and interesting research from Berkeley Lab and UC Berkeley that show plans are photosynthesizing more in response to...

Copyright © 2023 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.