Windows like this would have to cost no more than ordinary windows plus whatever energy they can generate, at most -- with no maintenance or longevity issues added to the mix AND without being less energy efficient in terms of what heat they let in and out. That's a tall order.

Someone is already selling venetian blinds that present solar cells to the outside surface, which can be mounted inside OR outside. Might be more practical than this tech for now.

Thin film photovoltaics, which can be applied to windows and other flat surfaces, never caught on. I doubt this tech will either.