If one is going to use this setup to distill seawater, you either have to place your solar farm near the ocean or pump the seawater to wherever your farm is. Near the ocean, corrosion and hence depreciation is high, and further away the cost of pumping becomes significant. There will be a sweet spot where such solar farms will be cheapest to install.
It might be possible to install these with residential solar plants to recycle water, but then you do have to pump dirty water up to the roof where solar panels are usually installed.
The amount of water distilled sounds quite good too. I think 1.5 litres/m2/hr. I guess you could have separate solar and water things but maybe it's cheaper to put them together.
Of course cost is going to determine whether this is practical to deploy, but products don't spring forth form Zeus' head fully formed. We should expect they'll need time to iterate on BOM cost and performance.
