Hermetic R290 units are playing a role in European supermarkets.
Emerson Climate Technologies has designed hermetic scroll compressors specifically to support a wide variety of propane (R290) applications in supermarket and convenience stores, accommodating growing demand in Europe and the U.S. for future-proof, hydrocarbon systems.
“We believe hydrocarbons have a role to play,” said Venugopal Kandi, product manager, refrigeration marketing for Emerson Climate Technologies’ Aachen, Germany-based division, at Chillventa 2016 on 12 October in Nuremberg, Germany.
In Europe, hydrocarbons are used in self-contained display cases and cold-room applications, typically with a maximum charge of 150g; in some parts of Europe like Germany and the U.K., charge levels are known to be as high as 500g or 700g, with permission granted by local authorities, said Kandi.
Larger-capacity display cases are using secondary systems with R290 on the high side and water/glycol to cool the cases. Small cascade systems, using propane and CO2, are also available for cold rooms (Whole Foods recently became the first U.S. supermarket to install a propane/CO2 cascade system).
While hydrocarbons are a “proven refrigerant” for low-temperature cases, they can now be used for medium-temperature cases as well, he added.
The hermetic design of Emerson's compressors is meant to “reduce the risk of having any leaks” of the hydrocarbon refrigerant, classified as flammable (A3). In addition, the compactness and light weight of scroll compressors “really fits into the small system architecture” of self-contained display units and cold rooms, said Kandi.
Emerson’s line of 14 heretic scroll hydrocarbon compressors, which range in capacity from 1.5 kW to 22 kW, can be applied to small-charge display cases, larger charge units and chillers incorporating secondary and cascade systems. To improve efficiency, some of the compressors include variable-speed controls.