No, they claim no moving parts for the generator, but refer to engineering designs that use pumped liquid tin to move the heat within the system. Clearly the challenge there is building a pump that can handle liquid tin at 2400C.
I could be wrong, but I don't think you'll find EM pumps in use for any liquid metals at temperatures above about 1000C. The 2400C temperatures required for this thermal battery concept present a significant materials engineering challenge for anything that touches the heat storage medium. There just aren't many mechanically sound, or electromagnetically capable solid phase engineering materials to work with at that temperature.
I'm not saying what they describe can't be done, only that getting the photovoltaic part to work isn't the biggest engineering challenge the concept faces.
I think the sheer size would make it interesting. The heat energy potential of acres full of graphite is enormous and presumably much cheaper to construct than an energy equivalent battery. Now I wonder how it holds up to other methods of storing energy.
