Cold Link Africa October 2019 | Page 17

PROJECT INCORPORATING COLD CHAIN their replacement refrigerants, have led the supermarket industry having to look to alternative, long-term, future proof energy- efficient solutions. Carbon dioxide (R744) is rapidly becoming the industry choice for retail and industrial refrigerant due to its favourable environmental properties (ODP = 0, GWP = 1). “CO 2 is a low global warming potential (GWP) refrigerant and an excellent choice when it comes to reducing greenhouse gas emissions,” explains Robinson. CO 2 provides high performance and exceptional properties for heat reclaim, due to its high heat transfer capabilities. CO 2 has excellent volumetric efficiency (more than five times the cooling effect per volume as R22), resulting in reduced compressor and pipe sizes for the same cooling effect, lower consumption ratio (the ratio between inlet and outlet pressures from the compressor), and low viscosity (making it easier to pump). CO 2 is widely available as a by-product in several industries and the cost of CO 2 gas is very low. Another advantage to using a transcritical CO 2 system is that it operates on only CO 2 as opposed to a cascade system that uses HFCs as well (generally R134a MT/CO 2 LT). “When looking at the natural refrigerants, CO 2 can be used in public spaces like retail trading floors, where other natural refrigerants such as ammonia is limited,” explains Robinson. THE FUTURE So far, the client is very happy with the refrigeration installation and how it is running, confirmed Lopes. “The site is relatively new and therefore the plant has run for only a few months and while the initial indicators currently show good performance levels, we will continue to monitor the consumption,” said Robinson. Future plans include adding a coffee shop above the shop floor and a 1 200m 2 liquor store (which should be open by the end of the year). CLA LIST OF SUPPLIERS Owner   Evergreens Developer Triple J Architect / designer  LN Designs Project manager   CPE Consulting engineers Product suppliers CRS custom-built two CO 2 refrigeration packs for Evergreens. COLD LINK AFRICA • OCTOBER 2019 Wet services Pro Earth Civil Tuss Engineering Refrigeration CRS Product Supplier Compressor Bitzer  Controls Danfoss  Switch gear ABB  Brace plates heat exchange Swep Oil management ESK Emerson Condensers and coolers HC Heat Exchangers Evaporators HC Heat Exchangers Insulation Dalucon Racking Barpro Storage www.coldlinkafrica.co.za 17