Besides a doubtful long term profitable economic business model, I would like to believe wind and wave are sustainable, but they are actually removing kinetic energy from the environment, which has to have an effect, one way or another.
Putting two and two together, I wonder if it has any effect on the rotation speed of the planet, that is where the kinetic energy of Earth surely manifests.
The frequency of leap seconds insertion into nuclear clocks tells us more than most would like to admit.
An almost imperceptible change is still a change, and we might see ways to undo the first order effect, which is the rotation speed of earth, but it would be much more difficult to correct the more insidious second order effect, the subsequent change of our orbital path around the sun, caused by stopping the spin of the "curve ball" that is our planet, in mid flight, away from the sun, the only real source of energy, which we must actually plug into, or die, sooner or later.

Conversely, it turns out when we look at any effect on spin that massive solar energy will have, when we finally get to it, will be positive, the opposite of taking kinetic energy out, it will be putting it in.