Turning a problem into a solution: aquatic clean energy from vortex-induced vibration?

Review of a paper on extracting energy from ocean currents, over at Skulls in the Stars

What is vortex induced vibration? In short, it is an effect by which little ‘whirlpools’ of fluid form in the wake of an obstructing object and regularly detach from it and are pulled downstream. These vortices carry energy and momentum (or, more accurately, the fluid which they consist of carries it) and when a vortex leaves, the obstruction itself gets a little ‘kick’ of motion from its departure. Vortices tend to leave the obstruction from opposing sides of it, and the net result is that the obstruction experiences an oscillatory force transverse to the direction of fluid flow.