How this 'artificial blowhole' aims to make wave energy mainstream

There's a large cement structure off the coast of King Island in Tasmania, Australia, that looks like some kind of futuristic sound-weapon. But have no fear, it's merely the latest in wave energy technology. Called the UniWave200 and made by Wave Swell Energy, this "artificial blowhole" is a fresh take on a classic wave energy converter known as an oscillating water column.

As incoming waves flow into the chamber, air is compressed, which spins a turbine. But while most OWCs are bidirectional, meaning the turbine spins as air is pushed out by the rising waves and when air is sucked back in by the receding waves, the UniWave200 is a little different.

According to Wave Swell Energy Co-Founder and Executive Chair Tom Denniss, scale model tests actually showed a unidirectional turbine was more efficient than previous bidirectional turbines. The increased efficiency of a unidirectional turbine might help the UniWave200 achieve its goal of making wave energy into a mainstream renewable like wind and solar.

Denniss said the UniWave200 also has advantages over previous wave technologies in terms of accessibility and durability. Because the UniWave200 has no moving parts below the surface of the water, damage from the pounding of the waves is less likely and repair teams will have an easier time making fixes.

The UniWave200's potential usefulness extends beyond the realm of green energy. Desalination and hydrogen production could conceivably be built into future UniWave200s, since the basic materials needed for each process  -- water and electricity -- are readily available.

But Denniss believes the most urgent use for this technology is as a form of protection from coastal erosion. For low-lying island nations threatened by more severe storms and rising sea levels due to climate change, investment in seawalls could prove to be necessary. With the incorporation of wave energy technology, these potential future seawalls could not only pay for themselves but also generate revenue and green energy for communities on the front lines of the climate crisis.

But first, the UniWave200 at King Island will have to lead the way. The first of its kind anywhere in the world, it's expected to be hooked up to the King Island grid in late February and be generating electricity by the end of March.

Denniss tells me the UniWave200's starting cost is below the starting cost of wind and solar at the same point in its development, and he predicts the cost will decrease at a similar rate as the technology scales up.