Traffic seems to have dropped over the last month or so.
Note that isentropic efficiency is NOT the same as cycle thermal efficiency. To get net cycle efficiency, you have to multiply the theoretical Carnot thermal cycle efficiency by the isentropic efficiency. As an expansion engine, the scroll engine is generally pretty darn efficient in your air conditioner, I think the number is typically well over the eighties and into the nineties in some cases. For a high efficiency Rankine cycle, the engine design is usually chosen to be such that the expansion ratio is considerably higher. The typical built-in compression ratio of a diesel is around 20 or so.