Batch thermosiphon

I didn’t really know where this should fit I don’t think there’s a heating forum. Anyhow I want to create a hybrid water heating system I have a pile of old solar hot water panels, I would also like to do a wood stove hot water loop. I like the idea of thermo-siphons for their simplicity and lack of fail points especially in an outage situation. The problem obviously is that the tank needs to be up high. Practically speaking I can only put a tank so big on the second story of my house. The ideal place for a large storage tank is my basement. I had the idea of a hybrid system. What if I had a smallish tank maybe 25 gallons upstairs with a thermosiphon when this reached a specified temp say 130 degrees it could dump the the basement tank being refilled with cooler fluid from that tank. The upstairs tank can be vented to atmosphere in the event of an extended power outage or pump failure that tank can overheat all it wants. There’s many more details I could discuss but that’s the gist of the basics. Anyone ever see anything like this?

Did you get any where with your design Jeff? It sounds like it ought to work. I've only come across syphons as you describe in sewage treatment.

No winter got busy and I never ended up building anything. Maybe next year