Cold Storage: Calculate Your Energy Loss From Old Doors
October 11, 2021
Maintaining the right temperature is critical to preserving the quality of fresh foods and produce in any cold storage facility. But if you’re using traditional overhead doors, you may be experiencing significant energy loss – and the increased cooling costs that come with it.
That’s because these doors often have inefficient seals that leak refrigerated air, forcing cooling systems to work harder to keep your room at a consistent, cool temperature.
A recent study found that more than half of organizations plan to increase their investment in energy efficiency, renewable energy and smart building technology in 2021, driven by the need to reduce energy costs.
Wondering how much energy you’re wasting? Take a look and find out.
Calculate your energy loss
In a cold storage facility, the cooling system’s main job is to remove heat from the air in the room. The total amount of heat that must be removed is called the “heat load,” and it comes from four sources:
- Heat Conduction (HC) - heat entering through insulated walls, ceilings and floors.
- Field Heat (FH) - heat that leaves produce as it cools to the storage temperature.
- Heat of Respiration (HR) - heat generated by produce as a natural byproduct of its respiration.
- Service Load (SL) - heat from lights, equipment and people, heat from warm air when the door is opened, and heat that enters by air infiltration past faulty door gaskets and through other cracks.
The total heat load in a cold storage facility is the sum of all four of these heat sources.
A poorly insulated door contributes to the heat acquired from the service load, which is estimated to be 10% of the heat from the other three sources in a cold storage facility. Calculating the service load can help you understand how much energy you’re wasting through inefficient traditional doors.
To calculate service load, use this equation:
0.10 x (HC + Hourly FH + HR) = SL Btu/hr
See this example of calculating service load for apples in a cooling facility.
Benefits of high-performance doors in cold storage facilities
When it comes to energy management and productivity, doors are sometimes overlooked as an opportunity for improvement. High-performance doors can help prevent the infiltration of warm air into food storage areas and reduce energy loss through service load.
Significant energy savings. At a major food production and distribution facility in suburban Chicago, high-speed doors have reduced energy consumption by 40%. They also minimized operating time on the refrigeration system for longer life because it didn’t need to work as hard to compensate for energy losses.
Less air exchange. Specially designed seals on the sides and bottom of high-performance doors form a tight, energy-efficient seal when they are closed. This protects against air exchange between cooled areas and warmer areas. Effective seals also save you money by ensuring that your building’s HVAC system doesn’t have to work as hard to maintain the cooler at a constant cool temperature.
Minimal energy loss. High-performance doors are manufactured with energy-efficient materials, such as insulated panels, that have a high R-value. This thermal feature helps them minimize energy loss when they’re closed.
Fast opening and closing speeds. Because high-speed doors can have an opening speed of up to 100 inches per second or more, air infiltration into refrigerated and frozen food processing and storage areas is kept to a minimum.
Rytec high-performance doors help increase productivity, reduce energy costs, and improve traffic flow and safety in cold storage facilities. For even more information on cold storage doors download our newly updated 2nd edition eBook, Knock Temperature Differentials Out Cold - Selecting the Right Cold Storage Door here.
If your facility still uses traditional overhead doors with inefficient seals and materials, it’s time for an upgrade. Contact us today to discuss how a high-performance door can help you maximize efficiency and save energy costs in your cold storage facility.