Cool. This kind of passive energy generation is what I think we need more of. I wonder if wave generation provides a more steady supply than wind?

So many major cities worldwide are along or near coasts, and these are far less visible than wind turbines, so I imagine the nimby-factor would be less.
This would be very practical for 'developing' nations with smaller economies, where the average home uses far less electricity than in Western homes. They would have to invest in the infrastructure (just like they would for a conventional power plant), but then the 'fuel' just arrives free of charge.

I hope this will accelerate wave-energy development. It is one of my favorite kind of clean power and, unfortunately, it has been flying under the radar compared to wind and solar.

Wave power may not be 'steady', per se, but it is very predictable, which is a good thing. That said, wind farms are getting pretty good at day-ahead forecasting of generation.

I have seen these before, and have wondered how many of them in a certain place might actually alter the tides/waves/etc. and what effect that might have on other things, like wildlife? I'm not saying anything bad would happen, I'm just hoping to learn more. Does anyone know the side-effects, if any?

isn't this going to hurt marine life? what if a whale gets stuck behind one of these things?

They are just floating buoys. How could a whake get stuck "behind" it?

Waves generate "eddy currents" which scribe a cylinder of water movement with an axis parallel to wave direction.

Imagine you are looking at wave passing from left to right in front of you. These waves spin the cylinder of water "clockwise". At the base of this cylinder, if wave energy is high enough, another is created that spins counterclockwise. When wind direction shifts there is a period of great turbulence, after which the eddy currents realign with wave direction, etc. The wave energy generators will sap energy that ordinarily would have been dispersed to the eddy currents, Thus, they will be smaller in diameter or slower. If deployed in shallow (littoral) zone, the impact could be accretion (buildup) of sediments down-field of the generators.

I imagine in some cases, the nimby factor may require them to be parked on or past the horizon (if they are ok being that far out), and if they are closer to shore, I'm sure they will have less detrimental effect than the breakwalls most cities build to protect shorelines and reduce storm damage. I'm sure that around most large coastal cities, the the shoreline has been drastically changed for decades or centuries, by human intervention.