I came across this while searching the web, it is old news it looks like but still news to me. It looks like this is from 2008. Has Toyota introduced this technology in any Prius since? Development of New Generation Hybrid System (THS II) - Development of Toyota Coolant Heat Storage System thanks, Steve
They introduced this in the gen 2 model. Its the tank thats in front of the drivers side front tire, hidden in the bumper.
I think that has been done....and moved on from...... That's the coolant thermos in the 2nd Gen Prius. The 3rd Gen uses what Toyota calls a heat reclamation system (process) or heat recovery system to achieve similar results and benefit sans coolant thermos.