Why not use two unidirectional turbines - one on the valved air and one as they use currently - if you have already split the air then you already have the two streams each flowing in unique directions

Nothing really new. Since 2011 a similar facility in the Basque Country works with more failures than benefits. Especially for the noise it generates, dubbed "The Dragon De Mutriku". http://manuelricosecades.blogspot.com.es/2011/09/mutriku-energia-de-las-olas-en-el-pais.html https://www.youtube.com/watch?v=udLxESuK5fI

The designers have abandoned the idea of using both cycles of wave because it's too tricky to arrange valves around a single large turbine and generator. Surely then the answer is to have two smaller turbines with generators. Simply reed valves, such as used in racing two stroke engines, would divide wave power between the turbines very efficiently. The cost of two smaller turbines with generators might even be less than one larger unit. And of course both wave cycles can be used.

Scale models using this principle have been around since the seventies. Maybe get a little more excited when a full size pilot has survived a winter at sea?

The argument for intake-only power generation seems weak. The scheme gives up fully half the generating potential for "simplicity". The same sort of valves that waste the out-rushing air, could redirect the flow so that the turbine would rotate the same for expulsion of air as for intake. Perhaps there are reasons to sacrifice half of the energy, but to just dismiss it requires solid reasons, not just a vague reference to simplicity.
The vaunted Paris Agreement does NOT quite pledge to "keep global temperatures from rising more than 2° C". Instead, it intends to keep the (current?) climate models from PREDICTING that temperatures will rise that much. The inference about it being a "crucial goal" depends on two things: (1) that the models are accurate and (2) the economic consequences, as documented by ... um ... by ... um, well, by politicians at a guess, will be very bad. Both of these assumptions are debatable.

http://geosci.uchicago.edu/~moyer/GEOS24705/Notes/Bernoulli.pdf
"That permits easy comparison of energy extractable from a flowing fluid, regardlessof its density. Since air is 1000 times less dense than water, the “effective head” of a stream of air will be 1000 times less than one of water moving at equal velocity."
So in this design the air velocity generated by the 'blowhole' would need to be 1000 times that of the incoming wave to achieve the same energy content. Which begs the question- why bother? Why not extract energy directly from the water??

OMG! If those sound anything like the Dragon, it will be heard for 20 miles in every direction, and 300 miles underwater. And the aquatic animals have likely left the area entirely. I agree about valving the air so it runs the generator the same direction at all times, harvesting the energy instead of wasting it on reversal. But the sound level is what may be key, both in and out of the water. This brings me to wonder whether the Netherlands wind park is also creating horrors of sound underwater. Another caveat is that whenever anything is erected in the ocean where there is any current, it will (not might) undercut/scour the ocean bottom at that area. When I lived there, I remember that the beaches in SoCal needed to be rebuilt every few years due to that phenomenon.

Every other comment seems onto this too. From the start they have given up half there efficiencey with the one way action there is no way its going to match the efficiency of a 2 way system its just your average enviro tech start up trying to juggle the numbers untill it sounds good.

the concrete should be salt resistant type,like romans used @2000 yrs ago

First, this thing won't survive the pounding of the ocean. Harvesting energy from the air seems very inefficient since it would be so much easier to let the water drive a turbine directly. Output would be very erratic depending on the weather and tides. Why doesn't someone design a blowhole style pump that would pump the water to a land based reservoir and drain it back through a hydroelectric generator at a constant rate?