Note that the NyTeknik article is an interview with Levi, so it is from the horse's mouth. Among other things it says that power peaked briefly at 130 kW. Now I see why they used such a high flow rate!
This makes me even more nervous about the prospects for a 1 MW reactor. The article confirms my suspicion that they used tap water directly. This is a perfectly good technique. Water-mains pressure in most large urban areas is constant for many hours, in my experience. Mizuno also confirmed this. Anyway, it seems they used some sort of flow-meter. The English is a little unclear. It says they "read input volume on a counter" to keep control of the flow. I asked them whether "counter" means "flow meter" and if so, what kind of flow meter. - Jed
