They reduced the batteries needed for an existing system by improving the control module and pump motors to more rapidly adjust to sunlight variation. It's good, but more of an iterative improvement.
Also... It's not a novel solution, and tbh it's a little unclear if it's an actual improvement at all.
For example, looking at the pictures it seems to be maybe a 1500 watt solar system. Such a system might need a $500 mppt charger and a $600 48v, 50amp battery. Their system still needs the charger and a battery of some sort. So, how do thier equipment cost compare to the old system? They don't really make that clear at all. Also, their efficiency metrics don't really make sense to me. It'd be nice if they'd produce a figure like gallon per watt between two comparable systems running under identical conditions on location.
Anyway, the whole think feels a bit self aggrandizing.
Desalination is not rocket science, it's something that people have been doing for hundreds of years, maybe thousands. Of course when it is done on a larger scale, it is done differently that in diy solutions but both approaches have one common problem (regardless of the the technic used, distillation or reverse osmosis): they are energy intensive.
The innovation that this collaboration created is in relation to the specific problem that this process has. The improvement is that not only they used solar power for this process but they actually eliminated the need for batteries. This means that they came up with a solution that tackles the actual problem desalination has. Apart from that they, they successfully tested it in the real world and it looks like they are launching a company in the next months, so it will be available to those who need it.