Dave, I'm really thrilled about your latest video, because you nicely explained the Thermodynamics in a very comprehensive manner.

Even Black Body radiation (Stefan Boltzmann law) was mentioned.

You mentioned several times that producing heat is always 100% efficient.. the thermo dynamical reason is, that all energy forms, like mechanical, electrical, chemical, atomic, may all be transferred in another form, down into heat, which is the last and least valuable one. That's an implication of the 2nd theorem of Thermodynamics, that any form of 'inner energy' will always be transferred irreversibly into heat, or in other other words, entropy is always increased.

If anybody claims, that his heat generating process to be >100%, then he also tries to violate another implication of the 2nd theorem, 'there does not exist a perpetual motion machine of the second kind'.

And that's exactly what SOLUS try to implicate, with their voodoo Graphene, and all their wish-washy statements, that their panel delivers still heat, when switched off.

You have put it right, instead, by pointing out that all such heaters simply store the initially consumed (electrical) energy in their body mass, which of course can be emitted later on.

Frank