Although never mentioned implicitly I believe the main thing...

Although never mentioned implicitly I believe the main thing holding this back is the economics of the process, i.e. is it sufficiently profitable for companies to want to use it. The tech is a great idea, companies will see that, but there is obviously something preventing them from committing (as we have seen time and again) which is most likely down to profitability. The annual report mentions that they are working on proving the profitability of the plant. Let's hope they can as this may be the hurdle that we have been stumbling on for the past many years and without profitability the tech is doomed however clever the process.