Passive Cooling for Static Storage Reefers
The Challenge
How can fleets reduce TRU runtime and diesel consumption on stationary frozen trailers without adding energy demand or operational complexity?
Refrigerated trailers parked at distribution centres and loading facilities spend extended periods stationary under direct solar exposure. Roofs absorb intense solar radiation throughout the day, forcing transport refrigeration units to run longer and harder to maintain set-point temperatures. The result is higher diesel consumption, accelerated TRU wear, and increased maintenance costs, compounded over a fleet of hundreds of trailers.
The Solution - PolyFrost
PolyFrost, ChillSkyn’s passive cooling coating, was spray-applied to the roof of a stationary refrigerated trailer operated by a major North American food manufacturer. Performance was monitored against a pre-coating baseline.
PolyFrost is engineered to reflect solar heat, maintain cooler roof surfaces, and reduce thermal transfer into trailer interiors, thereby cutting the heat load without any added energy.
PolyFrost
PolyFrost is a spray-applied, passive radiative cooling (PDRC) coating designed for sun-exposed surfaces in transport and industrial applications.
Reflects Solar Radiation
Reduces surface heating.
Maintains Cooler Interiors
Without adding additional energy demand.
Scalable and Easy to Apply
Using standard spray equipment, just like paint, in under 12 hours.
Effortless Maintenance
Regular cleaning with soapy water ensures long lasting peak performance.
Results
Field Trial
- North Carolina, USA - AUG - OCT 2025
- Monitoring period: 76 days | 611 hours
- Data points: ~15,000
- Unit: ThermoKing transport refrigeration unit (TRU)
- Method: Using TRU's evaporator fan state to determine engine on/off cycles
Uncoated trailer and PolyFrost-coated trailer thermal image comparison.
(North Carolina, August, 2025 @ 2PM - 26°C)
Performance Comparison | |
|---|---|
Annual diesel savings* | $3,066 |
Average TRU duty cycle | 49.4% → 39.7% |
Daytime TRU load reduction | ↓20% |
Nighttime TRU load reduction | ↓17% |
Diesel saved per trailer/year | 876 gallons |
Annual maintenance savings | $1,314 |
CO₂ reduction per trailer/year | 8.9 tCO₂e |
Key Impacts
Significant TRU Runtime Reduction
PolyFrost reduced daytime TRU load by 20% and nighttime by 17% — fewer engine hours mean less wear on compressors and extended TRU service life.
Meaningful Fuel and Cost Savings
876 gallons of diesel saved per trailer per year — roughly $3,066 in fuel savings* plus $1,314 in avoided maintenance.
Reduced Emissions
~8.9 tCO₂e avoided per trailer per year, supporting fleet sustainability and ESG reporting with no operational changes.
Simple, Non-Disruptive Application
Applied in under 12 hours with spray equipment. No downtime beyond the application window, no changes to operations.
* Based on current US diesel pricing