It seems to be about buffering heat energy for district heating in a CHP (combined heat and power) generation station, in presence of fast electricty market swings (think wind power). So would allow the CHP plant to ramp up generation quickly to supply electricity at a high hourly price, while buffering the produced heat peak to be more slowly drained to the district heating network.
Against this background it seems relatively cheap to build for the small size of plant in the picture, vs water tanks, and less risky (water entering the DH network has to be >100 C which means pressurization which in a big tank means a risk of a big boom).
It's true that water is pretty great for this also due to high heat capacity and that's why most existing heat batteries in cities are using water, that's why this is "novel" and "patented"...
Against this background it seems relatively cheap to build for the small size of plant in the picture, vs water tanks, and less risky (water entering the DH network has to be >100 C which means pressurization which in a big tank means a risk of a big boom).
It's true that water is pretty great for this also due to high heat capacity and that's why most existing heat batteries in cities are using water, that's why this is "novel" and "patented"...