Tidal turbines are viable in inlets where currents are consistently strong during tidal changes, the problem is they often disrupt the ecosystems around where f

Tidal turbines are viable in inlets where currents are consistently strong during tidal changes, the problem is they often disrupt the ecosystems around where fish need to spawn. Altering the total water flow into estuaries is sketchy and the good places are typically shipping lanes. You could put them in a place like Gibraltar and live with reduced water exchange in the Mediterranean, but it will be met with a lot of resistance. Ideas that rely on moving a mass up and down 10 feet every 6 hours require floating platforms the size of Rhode Island. Not cheap to build. Neither strategy is a contender in my book. I recall a research project in France which the results were unappealing. The environmental costs were high and power generated was low. You have to be careful getting scientific knowledge from the mainstream press or researchers who need to sell their research which means it is more akin to marketing than scientific knowledge.