Power electronics for novel heat pumps achieves efficiency of more than 99.7%

https://techxplore.com/news/2023-07-power-electronics-efficiency.html

"enable efficient heat dissipation, do not require compressor technology and refrigerants... electrocaloric heat pumpswell over 50% maximum theoretical coefficient system level.performance... completely emission-free heating and cooling... semiconductor gallium nitride increase power density and efficiency"

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New research may point the way towards frost-free heat pumps
https://techxplore.com/news/2023-09-frost-free.html

Heat pumps are everywhere — even in clothes dryers
https://www.canarymedia.com/articles/heat-pumps/heat-pumps-are-everywhere-even-in-clothes-dryers