It is still a work in progress

"We are currently optimizing the system to maximize the hydrogen production rate and to facilitate the collection of the produced fuel, " he said. "Ultimately we envisage using the solar paint as a cheap alternative to traditional photovoltaics." Photovoltaics, also known as solar PV, refers to a way of directly converting sunlight into electricity.
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But this method is cheap and also uses less energy consuming method compared to the electrolysis of water to produce hydrogen which uses so much energy to produce the hydrogen fuel that it becomes costly to produce hydrogen fuel.