The inventor/founder at the center of the article, Lonnie Johnson, was on the team at JPL that designed and implemented the thermoelectric generators (heated by radioactive decay from plutonium-238 pellets) on the Galileo spacecraft sent to Jupiter. So I would expect that he’s more familiar with the thermodynamic and engineering challenges than even a typical expert.

The PR fluff put out by the company mentions that the theoretical basis for this specific type of generator was worked out a while ago but needed materials science to advance to the point where this type of generator can be thermodynamically and commercially feasible.

Looking at how this generator is supposed to work, it’s interesting in that it does rely on the movement of fluid, but is supposed to be a totally closed loop, to be a bit different than the pure solid state, semiconductor-based Seebeck generators that are already well known.

The other area talked about in this article is that they believe that it can be effective with lower temperature differentials than any previous technology, which might make a huge difference in whether it can be deployed to more useful places and thereby make it economically feasible more easily than prior concepts.

In the end, if these generators can output some electric voltage/current, it might just take on similar generation characteristics as photovoltaics, which could mean that hooking these up to the grid could draw on some of the lessons learned from the rise of grid scale solar.