In fact, over in South Korea, scientists seem to have developed what is being referred to as “blue energy”, where through the use of a specially formulated membrane, it could have the potential to generate energy from rivers that could be used to replace nuclear power plants. This “blue energy” involves a membrane that leverages the chemical differences between fresh and saltwater to generate electricity.
This also takes advantage of nature, where rivers dump about 37,000 cubic kilometers of freshwater into oceans every year, so this membrane will actually make use of that occurrence to generate electricity. According to the numbers, this tech could have the potential to generate 2.6 terawatts, which is equivalent to the power generated by 2,000 nuclear power plants.
This tech has been explored before in the past in 2013 by French researchers, but it was only until recently that researchers managed to make it even more efficient. The researchers believe that there is still a lot of work to be done in making it better, so it could be a while before we actually see it replace nuclear power plants for real.