Integrated halide perovskite photoelectrochemical cells with solar-driven water-splitting efficiency of 20.8% - Nature Communications

Almost Perfect (in the lab)

New Solar Direct conversion of sunlight to hydrogen...

Rice University has managed to run a lab scale solar to hydrogen converter for 102 hours, and using a new water proof coating on the solar cells, converted sunlight to hydrogen at a 20% rate (normal PV is 21% efficient at converting sunlight to electricity).

Now it has to scale, operate for thousands of hours, and the cost has to be reduced to a commercially acceptable level. By 2030 or 2035 if everything goes right, instead of 70% conversion, we may be at 95% conversion of sunlight to hydrogen. But the path is long and many lab level devices never make it to commercial scale. I wish them luck.