The efficiency of a machine isn’t measured at how effective its job is, but how efficiently it does that job. If it moved heat without producing any waste heat, it would be 100% efficient. If it produces any waste heat at all it’s not 100% efficient. No machine can ever be more than 100% efficient. That would violate the laws of thermodynamics.
The efficiency of a machine isn’t measured at how effective its job is, but how efficiently it does that job. If it moved heat without producing any waste heat, it would be 100% efficient. If it produces any waste heat at all it’s not 100% efficient. No machine can ever be more than 100% efficient. That would violate the laws of thermodynamics.
Hence why I clarified what it was efficient at doing.