Reducing Energy Use in a Walk-In Freezer

Reducing Energy Use in a Walk-in Freezer with IceRack™

The Challenge

Many energy technologies are designed for large refrigeration systems, but smaller commercial and industrial freezers also face rising energy costs and reliability concerns. A food production facility, Kids’ Food Basket, in the Midwest wanted to evaluate whether thermal energy storage could reduce refrigeration energy use in a 500 sq ft walk-in freezer without requiring changes to its existing system controls.

The Solution

IceRack™ thermal energy storage modules were installed directly inside the freezer. The system operates passively, charging and discharging thermal energy as the refrigeration system cycles, without requiring additional controls or changes to freezer setpoints. Measured performance showed consistent reductions in refrigeration energy consumption. To evaluate performance, engineers developed a weather normalized baseline model using daily energy consumption
and outdoor air temperature. The model showed strong statistical performance with CV(RMSE) of approximately 4.3% and negligible bias, meeting ASHRAE Guideline 14 standards for measurement and verification. Post-installation energy use was then compared against the modeled baseline to determine the impact of the IceRack™ installation. Since this solution is manufactured in the US, Kids’ Food Basket can take advantage of the Investment Tax Credit, further reducing the cost of the project. 

Key Takeaway

This project demonstrates that IceRack thermal energy storage can deliver meaningful energy savings not only in large cold storage warehouses but also in smaller refrigeration systems like walk-in freezers. Because the system operates passively and does not require control changes, it can integrate easily with existing refrigeration equipment while still delivering measurable performance improvements. Because of this project, 1,500 more nourishing meals will be served every year.

Results

• 23% average daily energy reduction

• Efficient Load Shifting: Stores cooling energy overnight, reducing reliance on high-demand electricity during the day.

• Enhanced Freezer Efficiency: Up to 20% efficiency gain lowers strain on refrigeration systems, increasing reliability.

• Environmental Impact: Expected to cut more than 12.8 metric tons of CO₂ annually—the equivalent of removing 3 gas-powered cars from the road for a year.

• Cost Savings: Projected to save over $3,000 annually