It does no such thing.
It was only a lab experiment.
Even if 7x more efficient i doubt that my outrageous electric bill would ever go down.
Believe they might be comparing performance with the intended Soviet radar satellite powered by TOPAZ reactor with thermionic converter.
A Stanford development(PETE) which looked good for a certain project; but, couldn’t be used with 3500 K radiant source. They went with 2000 sun concentrator photovoltaic for research prototype—verifying cooling system can properly extract waste heat with a ‘cheap’ single layer. Only 11% efficient but still kicks out 22 kW.
https://gcep.stanford.edu/pdfs/PETEtalk_gcep2010_Melosh.pdf
Time to invest?
The new technology remains in development and it currently only functions in a vacuum chamber.
...
In other words, it’s still not being used and this particular research will probably go nowhere.