250,000 SF Cold Storage Facility

Project at a glance

Scope delivered

• Utility coordination & MV service. 25kV class primary service from CenterPoint Energy, pad-mount switchgear with primary metering, and a 2,500kVA pad-mount service transformer. Service entrance sized at 3,000A / 480V secondary with documented growth headroom for the operator’s planned ASRS expansion in year 3.
• Refrigeration plant power. Dedicated MCC for the ammonia refrigeration plant supporting three screw compressor packages, evaporative condenser fan motors, and refrigerant pump skids. VFDs on compressor leads for capacity control. Refrigerant detection wiring, machinery room ventilation interlocks, and emergency stop circuits per IIAR 2 and ASHRAE 15.
• Cold-space distribution. Branch panelboards inside the refrigerated envelope rated for sub-freezing ambient. NEC 310.15 ampacity adjustments applied to conductors in cold rooms. Vapor-tight LED fixtures throughout, sealed device boxes, and condensation-tolerant termination methods.
• ASRS & material handling. Power distribution for the unit-load ASRS at the back of the freezer envelope, with coordination of scope splits with the ASRS integrator. VFDs on conveyor drives, MCC for material-handling motors, and PLC interfaces to the warehouse management system.
• Dock & loading bay power. 38 dock doors with leveler, vehicle restraint, and dock light power. Refrigerated trailer plug-in receptacles (480V 3-phase) at each dock position with metering for cold-chain billing.
• BMS integration. Building management system interfaces to refrigeration plant (Danfoss AK-SM platform), HVAC for dry-storage and office, dock door interlocks, and lighting control. BACnet and Modbus TCP tie-ins through the BMS contractor.
• Life-safety systems. NFPA 70 Article 700 emergency power, NFPA 110 generator installation sized for refrigeration plant restart sequences plus life-safety load. Egress lighting rated for cold-temperature operation in freezer spaces.

The challenge

Cold storage projects rarely have schedule slack. The owner had a contractual energization date driving a 14-month build window, with refrigeration commissioning required to begin within 12 months of NTP. The critical-path constraint wasn’t field labor — it was utility coordination and long-lead switchgear procurement.

We engaged the utility transmission planning group during design development, before construction documents were issued. Long-lead MV switchgear and the service transformer were released during DD with the owner’s approval, six months earlier than typical plan-and-spec procurement. The refrigeration plant MCC was prefabricated off-site and delivered to the building shell before envelope close-in.

The outcome

Energization completed on schedule. Refrigeration plant commissioning began on the contracted date, with the plant operating at design capacity within 4 weeks of energization. Owner’s operations team accepted the closeout package without electrical punchlist carryover into year-one operations.