The perovskite semiconductors here are a very different technology than the old thin photovoltaics. They have the potential to be much more efficient, and the deposition techniques are cheap and comparatively low-tech
Whether they can succeed in simultaneously be highly-efficient, resistant to degradation in the environment, and still be low cost is the subject of a lot of work. We'll see.
They were supposed to be manufactured for the price of a lollypop per square meter back in the '90s.
To be more specific, the target back in the '80s and '90s was clearly articulated as being fifty cents per watt (where "per watt" meant, when illuminated at standard conditions of 1 kW/square meter.) Silicon photovoltaics can now be purchased at 12 cents per watt. In today's dollars. They not only hit the target, they blew it away.
The reason the thin films of the '80s and '90s lost was not that they were bad, but that silicon simply outcompeted them.
So forgive my skepticism regarding new breakthroughs.
I have some amount of skepticism too. Nanosecond lifetimes of hot electrons are amazing, but to date there's no way for turning hot electrons into electrical energy*. So they'd essentially have to invent a technology from scratch.
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*(thermoelectrics convert hot electrons into usable energy, of course, but there not just the electrons, but the whole lattice is hot. And the efficiency is worse than a solar cell).