There are currently no production heat pumps using the electrocaloric effect to my knowledge. Stirling engine I doubt as well. Either way still classes as refrigeration. In fact a Stirling engine heat pump/refrigerator would still need refrigerant as it needs a working fluid.
Edit: also pretty sure a Stirling engine is an implementation of a carnot engine
I was referring to electrocaloric, and Stirling engine heat pumps.
There are currently no production heat pumps using the electrocaloric effect to my knowledge. Stirling engine I doubt as well. Either way still classes as refrigeration. In fact a Stirling engine heat pump/refrigerator would still need refrigerant as it needs a working fluid.
Edit: also pretty sure a Stirling engine is an implementation of a carnot engine