Electrifying refrigerated trailers is one of the most effective ways facilities can reduce diesel consumption, cut emissions, reduce maintenance, and meet ongoing compliance requirements. Before investing in electrification, facilities need to understand how much power an eTRU uses, what it means for operating costs, and how those requirements impact ROI.

This article breaks down real-world eTRU power needs, what facilities should expect across common operating conditions, and how to plan electrical capacity that supports both today’s fleets and the next generation of refrigerated trailers.

How Much Power Does an eTRU Use?

Electric TRUs draw different amounts of power depending on whether they’re actively cooling down a trailer or maintaining its temperature. These modes directly influence how yards, warehouses, and distribution centers plan electrical capacity.

Pulling Down Temperature (Heavy Load)

This occurs when a trailer first connects to shore power and must pull the temperature of the trailer down to the required temp.

Typical power demand:

• 15 to 17 kW
  
• Duration: 45 to 60 minutes per cycle

This is the peak load a facility should account for when designing electrical capacity.

 Maintaining Temperature (Light Load)

Once a trailer reaches its target temperature, it enters a steady operating mode that represents the majority of TRU runtime.

Typical power demand:

• 8 to 12 kW
  
• Represents 80 to 90 percent of operating hours

This range is the most important for planning continuous load availability.

How eTRU Power Use Compares to Diesel TRUs

Understanding energy demand is only part of the equation. Many facilities also want to know how electric standby compares directly to diesel operation.

Here’s what changes when a TRU runs on electricity instead of diesel:

✔ No fuel burn during idle

A diesel TRU typically consumes close to a gallon of fuel per hour while maintaining temperature. Electric standby removes that consumption entirely.

✔ Lower operating cost per hour

Electricity is consistently less expensive than diesel across most commercial markets, leading to significantly lower hourly operating costs.

✔ Less engine wear

Reduced idling helps extend engine life and cut maintenance costs by reducing run hours.

✔ Cleaner and quieter operation

Electric standby eliminates diesel exhaust and reduces noise, improving working conditions and community impact.

Why These Power Levels Matter for Infrastructure Planning

Not every trailer operates at peak load simultaneously. Most facilities see a predictable mix:

• A few trailers in temperature pull-down
  
• The majority maintaining temperature
  
• Several unplugged, staging, or moving

Understanding this natural diversity helps avoid oversizing or undersizing electrical systems and ensures consistent power availability without unnecessary cost.

Circuit and Power Requirements for eTRUconnect

Electric standby systems rely on clean, consistent power delivery, and that’s exactly what eTRUconnect is designed to support. The system integrates the key electrical requirements needed for reliable TRU operation, including:

• 480VAC service to provide power to TRU’s
  
• 30 A branch circuits sized specifically for electric standby
  
• Built-in branch circuit protection for safe, compliant operation
  
• Safety-interlocked connectors that automatically cut power during disconnect

These design elements help ensure safe operation, protect equipment, and provide the dependable power TRUs need during both pull-down and temperature maintenance.

How to Estimate Your Yard’s Power Needs

Facilities can get a clear picture of required electrical capacity with a simple three-step approach:

1. Count Your Connection Points
   Include docks, yard positions, and any planned expansion areas.
   
   
2. Estimate How Trailers Typically Operate
   Most sites have a mix:  some pull-down, some maintain temperature, and some are unplugged or staging. Determine your general mix.
   
   
3. Apply the Expected Power Ranges
   
   • Pull-down: 15–17 kW
     
   • Maintain: 8–12 kW

This gives a realistic view of both peak demand and everyday continuous load. Leaving extra capacity helps accommodate fleet growth and future electric TRU technology.

Future Proofing: Planning for What Comes Next

Today’s electric standby TRUs operate within predictable power ranges, but the next generation of battery-electric TRUs will require more capacity, new connector types, and smarter power management. Preparing for these shifts now can help facilities avoid costly retrofits later.

Looking ahead, operations should expect:

• Higher AC power needs
  
• More diverse charging and connector standards
  
• Increased demand for monitoring and load management
  
• Greater emphasis on scalable infrastructure

Building electrical systems with future capacity in mind allows facilities to transition smoothly as technology evolves, regulations tighten, and more electric-powered equipment enters the market. Electrification is accelerating across the cold chain, and yards that plan ahead will be positioned to support both today’s eTRUs and the fully electric fleets of tomorrow.