These are promising projects, Solar is worthwhile deploying and very economically viable. Where I have some concerns is that these are relatively expensive projects to do for Solar, the cost of the flotation and extra cabling and corrosion of the water all add to the costs. Its a lot cheaper to deploy it on roofs and we have countless enormous numbers of business/industrial roof space that could be used for this with much cheaper maintenance and installation closer to where the power is used.

I would much rather see us deploy more Solar across existing buildings and above obviously useful spaces as shade like like car parks than in the water where its relatively expensive. Still if they have done the maths and it works out then more power from the sun and less from burning ancient plants is all positive from me, but we can make our investment go further.