At the 2014 Gustav Lorentzen conference in Hangzhou, China, a comparative study was presented examining the applicability of five single stage vapour compression heat pumps (VCHP) using the refrigerants R134a, R290, R717LP, R717HP and R744. The study considers operational and economic constraints such as refrigeration equipment availability and positive Net Present Value of Investment. It concludes that the LP R717, HP R717 and transcritical R744 heat pumps are advantageous when considering the
A project team working on an ammonia based indoor ski resort in Dubai resorted to self-regulation in order to prove to the local authorities that public safety would not be compromised. Mr Ali Sleiman, Director of engineering services company EN3 – The Three Factors Company, shares his experience from this project and discusses the suitability of ammonia in district cooling in the Middle East.
A pork processing plant in Minnesota, US has implemented three energy saving measures to its ammonia refrigeration system that cut annual electricity use by 4.35 million kWh. Measures included the addition of two evaporative condensers, new condenser controls and the installation of a dedicated bank of condensers to cool the compressor oil through natural convection rather than with a mechanical pump.