Two decades of optimism about glass fibre have produced a great deal of announced capacity and rather less installed capacity. That may be changing, because the demand drivers are now concrete rather than aspirational.
What changed
Blade length has grown faster than anyone modelled, and the material per blade with it. At the same time, battery enclosures have created a second demand stream with completely different performance requirements.
The capacity question
Announced capacity across the sector is large. Installed capacity is smaller, and the gap is the point: the constraint is not glass, it is the sizing and finishing lines downstream. Suppliers who have invested there are the ones with the order books.
What to watch
Whether the sizing bottleneck is relieved faster than blade growth consumes the capacity. It is not a comfortable equilibrium for anyone.
