Case Study

Kuehne+Nagel thinks ahead to reduce its CO2 Footprint - a new refrigeration warehouse in Auckland

 

The new facility had to be able to maintain a high level of efficiency while handling a wide range of our customer’s perishable goods from fresh produce through to sensitive pharmaceutical products with the added requirement of frozen goods. To meet these key requirements the decision was made to install a refrigeration system that used natural refrigerants due to zero rating for ozone depletion and negligible global warming potential (GWP).

 

 

Kuehne+Nagel‘s strong focus on environmental responsibility along with meeting best practice has driven the successful outcome of this project.

 

Global Warming Potential (GWP)

 

Our refrigeration system used natural refrigerants due to zero rating for ozone depletion and negligible global warming potential (GWP). A centralised ammonia (GWP=0) refrigeration system with a secondary glycol-water brine circuit delivering the cooling requirements to the medium and high temperature areas within the facility was chosen.

Energy Efficiency

 

To achieve a full natural refrigerant solution a sub-critical CO2 cascade system was used for the low temperature freezers. Along with satisfying the natural refrigerant criteria the CO2 subcritical configuration offers very high efficiencies in low temperature operations. Fan motors and main pumps were all selected with high efficiencies and variable speed control to minimise energy usage.

Temperature accuracy over 100 days

 

A programmable logic control system was developed to achieve close control of all system and room operating parameters. A full supervisory control and data acquisition system was incorporated into the control system to gather, analyse and report on the system’s real time data. The extensive use of LED lighting and insulated rapid roller doors throughout the facility.