Fernhurst Australia

Discover how Fernhurst's Truganina facility, a state-of-the-art 60,000m³ cold storage and refrigerated logistics warehouse in Melbourne, is setting new standards in energy efficiency with its ammonia-based refrigeration system.

Designed by Scantec Refrigeration Technologies, this dual-stage, low-charge NH3 plant achieves energy savings estimated at $400,000 annually, with a five-year payback period. The facility's reduced ammonia inventory (472 kg) and advanced "cold lake" air distribution system combined with automatic ambient air defrost enhance safety and operational flexibility, while also minimizing environmental impact.

Recognized as a finalist at the 2021 AIRAH Awards, Fernhurst’s Truganina project serves as a model for large-scale cold storage with natural refrigerants.

Requirements

Fernhurst, a leader in cold storage and refrigerated logistics, sought a solution to consolidate three existing facilities into a single, energy-efficient warehouse in Truganina, Melbourne. The primary goal was to replace traditional HFC and CFC air-cooled systems with a sustainable, future-proof alternative that would meet high energy efficiency standards and accommodate their varied cold storage needs.

Key specifications included a centralized, dual-stage, low-charge NH3 refrigeration system, capable of handling batch blast freezing for highly variable operations while minimizing ammonia inventory to enhance safety and regulatory compliance. Fernhurst also required advanced air distribution and defrost mechanisms to ensure consistent cooling, energy savings, and improved operational safety, alongside flexibility for dynamic storage and freezing requirements.

Solution

The centralised dual-stage, low-charge NH3 refrigeration plant with batch blast freezing at the new refrigerated warehouse in Melbourne is believed to include technical features which, when combined within one facility, represent a world-first. These are the key benefits and features:

• Energy efficiency and cost savings: Designed by Scantec Refrigeration Technologies, the NH3 system at the Truganina facility achieves a specific energy consumption (SEC) that is several times lower than conventional systems. With energy savings estimated at $400,000 per year, Fernhurst anticipates a five-year payback period. The facility's energy usage from product freezing alone is approximately 110 kWh/ton, showcasing its cost-effective operations.

• Reduced refrigerant inventory: By employing low-charge NH3 technology, the facility minimizes ammonia exposure risks. The ammonia inventory is 472 kg, significantly below the 2,000-2,500 kg required for conventional systems, allowing the site to avoid classification as a Dangerous Goods Storage facility. This reduced inventory enhances safety while maintaining cooling efficiency.

• Enhanced operational flexibility: The facility includes in-rack blast freezing modules that can be switched to pallet storage when not in use for blast freezing. This design accommodates the highly variable nature of Fernhurst’s business, optimizing storage and freezing functions within a single infrastructure.

• Cold lake air distribution: Utilizing natural air circulation, the facility employs a "cold lake" air distribution system, which leverages density differences between cooler and warmer air. This method reduces the need for mechanical airflow, leading to further energy savings and increased predictability in temperature distribution across the storage space.

• Automatic defrost and leak management: The NH3 system features automated ambient air defrost, minimizing heat ingress into freezer areas, enhancing operational efficiency, and improving occupational safety by minimizing the risk of liquid hammer. In the event of an ammonia leak, the defrost mechanism acts as a venting feature, ensuring that leaked refrigerant does not enter the refrigerated space, thus enhancing system reliability.