Thread: Low tech tidal power

Here's an old idea I had for floating docks in isolated locations. I thought of this after seeing a dock hung up in the air upon its own piling, as the tide had fallen.

Have a regular floating log dock. Build a powerhouse shack beside one piling. Now put a chain on the piling, and feed that to a spring: a spiral of old steel strapping will do - tempered so it's "spring steel" like a watch spring. Relay torque (it'll be very high, very slow at this stage) through a series of such spring "gears" and concrete flywheels until you can step up to belts and finally to a wee generator.

Enough for dock lighting and perhaps more. Driving a pump might be useful. Potable well-water or washing facilities are ammenities many isolated docks lack.

The weight - and alternately: buoyancy - of your dock's combined logs and timbers vs. tide cycle drive the generator. Massive docks drive larger generators.

Obviously the moon is a reliable energy source. The flywheels are provided to negate wave action - though maybe this dock requires sheltered waters. Just to make clear: wave action is not being harnessed. Tidal range is.

I was wondering about a ratchet of some sort to keep the dock in falling or rising state during slack tide (for uninterrupted generation) but the self-governing mechanism becomes big, complicated and greedy for maintenance.


Is this a realistic solution for isolated, largely unattended docks and marinas e.g. on islands?