Biomimetic sharktail wave-action harvester

Now there are a few words you probably weren’t expecting to read today. I have to say I’m a little skeptical of this system; after all, sharks’ tails are part of a supremely aquadynamic design and are powered by enormous muscles, not the waves, though I’m sure the researchers are aware of that. The system is designed to oscillate in the current, driving against a generator’s resistance to create electricity.

Now, I am not an electrical engineer, but it seems that these things will either require power to run, or only produce a little bit of power. I’m a fan of biomimetic design, but this seems like more a choice for designing a propulsion system than a power generation system. Any engineers out there want to comment?