Energy: tidal power: historical precedent

Self-tutoring about renewable energy sources: the tutor continues about tidal power.

I mention in my post from June 26, 2024 the idea of tidal power and why it might not be the most oft-discussed source of renewable energy.

Tidal power has its challenges, yet must be viable, because historical cultures used it. One way they did so was to dig a channel with a gate at the shore. Beside the channel a mill would be built, from which an axle would reach to a water wheel suspended in the channel. When the tide was coming in, the gate would be open to allow the channel to fill. At the tidal crest, they would close the gate, holding back the water. Once the tide had sufficiently receded outside the gate, it would be opened, allowing the captured tidal water to flow out like a river. The outflow would turn the water wheel, powering the mill.

Since those projects would have been hand-dug, and fairly small-scale, one might wonder if they had much environmental consequence.

Source:

The Canadian Encyclopedia: Tidal Energy