YOu can see from the spec that it is using a booster pump. 100 psi 2 gal per min running off a gel battery (33ah).
For this case study, the water is 120 tds.
The information I have is that, with only 100 psi you need approx 40% of water going to waste or you will knacker the RO very quickly. We have 125psi booster pump and we have 40% going to drain. They are working 3 RO's so they could be recycling. This would mean approx 7% going to drain.
But the 2nd filter will have 237 TDS water going through it and the final filter will have 570 tds going through
and the water will be 6 tds coming out.) They would need a DI polisher for this and there is not one present that I can see.
Also, the pump is rated at 2 US gallons per minute. This is approx 7.5 litres. However, this is "theoretical". The minute you attach a hose to it, the flow will drop due to resistance. Let's be generous and say they get 7 litres. 7% minimum goes down the drain. So the best they can hope for is 6.5 litres per minute.
Thus, the BEST they can hope for is 376 litres per hour and the water will NOT be pure.
Also, they claim 12 hr run time. Not possible. 100 psi pumps use approx 8 amps per hour. Thus a 33ah battery will run this for 4 hours only.
Seems to me that this setup is only useful for people with very low TDS supply water.