Packaged ammonia refrigeration units continuously improve. How to measure and present performance ?

This paper talks about recent developments in penthouse, packaged low charged units with ammonia as refrigerant. A special attention is given to clarification of the definition of various ways to present efficiency providing insights to opportunities for improvements of COP in design stage as well in operation. The schematics drawing of the facility for performance evaluation of the penthouse unit presents various balances when defining capacity and efficiency. Definition of the performance (Q and COP) and its measurements is very important at this point when new technology, packaged low charged units with ammonia is trying to fully establish position among units with synthetic refrigerants and industrial refrigeration systems with ammonia.