Another refrigeration system has just been successfully completed for a temperature-controlled logistics operator in Truganina, Victoria. The challenge of the project was the consolidation of three existing HFC-based refrigerated warehouses into one, with increased energy efficiency and reduced maintenance costs
One of the main issues for this particular cold storage facility were the incredibly high monthly electricity bills of around $75,000. With the new system, a minimum reduction of 50% in energy costs is anticipated and an electricity bill of around $35,000 per month instead.
The refrigerated warehouse design features cold lake air distribution and insulated coolers mounted in the ceiling cavity, automatic ambient air defrost and the facility is powered by a centralized, low charge NH₃ refrigeration plant (NH3 inventory 438 kg or 0.61 kg/kW). Aside from energy efficiency, automatic ambient air defrost also minimizes the potential risk of ammonia releases within the refrigerated spaces through an automatic venting function.
Energy Efficient Performance
The great benefit of using low charge ammonia technology, is the superior energy performance. We have documented energy performance improvements of up to 71% compared with single-stage, industry-standard, air-cooled HFC-based systems with electric defrost. This results in huge energy cost savings making a replacement system cash-flow positive as soon as it is installed.
Another great benefit to low charge NH₃ is that it is a natural and safe refrigerant making it environmentally friendly. With the ongoing HFC phase-down, freon based systems will need to be replaced in the near future making a low charge NH₃ system a completely future-proof and proven alternative to an HFC based system.
Other significant advantages of ammonia low charge technology are that the NH3 inventory is 30-50 times lower in the warehouse air coolers and 3-5 times lower overall compared with conventional NH3 plants with liquid overfeed. Furthermore, there is a 15-30% lower annual energy consumption than in conventional NH3 liquid overfeed systems. The latter is a result of the elimination of all refrigerant liquid within the suction line network of the plant.
The system installed in Truganina has a total of 25 kg NH₃ operating inventory in the air coolers installed within the total refrigerated volume of 60,000 m³. The annual energy consumption is approximately 1,000,000 kWh (storage only without blast freezing). It will be maintained by our in-house maintenance service team.
Another benefit to the client is that the annual maintenance costs will reduce significantly compared with the installations that the new plant replaced.