I've often thought why not dam a whole estuary or bay and use hydro to collect the energy on the the fall and rise of the tide. I know the environmental impact wouldake it unpalatable but are there any reasons it wouldn't work?
This type of project has been few and far between and I would guess they might be very costly to build and maintain compared to the harvested energy.
[1] https://en.wikipedia.org/wiki/Sihwa_Lake_Tidal_Power_Station [2] https://en.wikipedia.org/wiki/Rance_Tidal_Power_Station
It seems outright feasible and sensible in comparison.
240 MW, built in 1966.
https://earthsciencesociety.com/2014/05/01/a-tidal-power-lag...