I’m not so much concerned about it being an open system but rather that it relies on water as a process fluid. Sure running a geyser for 30+ years is fine if al

I’m not so much concerned about it being an open system but rather that it relies on water as a process fluid. Sure running a geyser for 30+ years is fine if all your losing is thermal efficiency. But in this case we are talking about sticking your neck out for 50% efficiencies. How long before fouling, pump degradation or just simply water sacristy cripples a system like this? Or simply renders it so inefficient to be superfluous?