Wonderful
And even though they are still developing this idea now I'm sure we can recover more energy from waste heat, more effectively than we have been, prices of this tech will drop as it develops and is utilised.
Just amazing what they were understanding over 2000 years ago, we miss the import of this.
i.e. the reason Archimedes had to discover displacement as a solution for the "is that all Gold" problem is due to the fact they were electroplating gold onto copper back then, and substituting electroplated gold statues for full gold statues.
Electroplating and batteries have been found in Nineveh around 600BC.