I don't see anything unique.. CO2 heat pumps have bee around for awhile too,.
About CHOFU’s CO2 Heat Pump System
CO2 heat pump system technology originates in Japan, and CHOFU has been manufacturing this product for nearly 20 years. Natural refrigerant takes in aerothermal energy, exchanges it, and uses it to efficiently supply hot water. It emits no greenhouse gases when supplying hot water, making it an indispensable product in creating a decarbonized society.