It’s an Open & Shut Case: Retrofitting Open Refrigerated Display Cases with Doors

You wouldn’t think of taking the door off your kitchen refrigerator and letting it run. But do you even give a second thought to seeing refrigerated display cases without doors in your local supermarket? We’ve become used to buying meat and dairy products from open refrigerated cases – but is that really the most efficient and effective way for retailers to offer these products for sale?

Let’s look at five reasons why retrofitting open refrigerated display cases with transparent doors makes economic sense for grocery stores, convenience stores, and supermarkets:

  • Save on energy costs: An open display case uses much more energy to keep food refrigerated, so adding doors to an open case will significantly cut a store’s utility bills.
  • Food stays fresh longer: Adding doors to an open display case helps keep the temperature at a constant, optimal level, meaning that food products last longer and waste due to spoilage is reduced.
  • More economical than replacement: Retrofitting an open display case with transparent doors can achieve the same result as buying a new refrigerated case at a much lower cost.
  • Lower maintenance costs: Since the addition of doors reduces the amount of time that condensers and fan motors need to run, those components will last longer and require less frequent maintenance.
  • Make additional upgrades: While you’re adding doors to your open cases, you can take the opportunity to add other energy-saving measures like LED lighting.

Now that we’ve identified these retrofit benefits, let’s take a deeper dive into each one.

We put energy cost savings at the top of our list because it’s the most impactful benefit. Supermarkets are the highest energy users among commercial buildings, primarily due to refrigeration needs that can account for more than half of their energy usage. With energy being such a significant operating expense, any reduction in energy costs for food retailers can help fatten their razor-thin profit margins. In fact, an ENERGY STAR® study estimated that every dollar saved on a supermarket’s energy bill is equal to a $59 increase in sales.

The energy savings result from the fact that an open case’s refrigeration equipment is operating primarily to battle the infiltration of warm air from the store. A U.S. Department of Energy guide on retrofitting open cases estimates that these so-called “infiltration loads” comprise 70% to 80% of the total case heat load, compared to only 10% for display cases with doors. In other words, about two-thirds of the heat that needs to be removed by an open case’s refrigeration equipment could just as easily be kept out by installing doors.

But that’s not the only way that display case doors save energy. If you look at this situation in reverse, it stands to reason that all of the chilled air that an open display case throws into the surrounding area makes the store’s heating system work that much harder. This is particularly significant for the heating costs of supermarkets located in colder climates. Customer comfort is also a factor when it comes to the cold air escaping into the store: No one wants to stand in a chilly blast as they search for their favorite flavor of yogurt.

Food freshness and safety is of paramount importance to supermarket owners, especially when dealing with perishable items like dairy and meat products. Maintaining a steady temperature that’s right for the products in the case will allow them to stay fresher for a longer period of time, extending their shelf-life. That helps cut the costs associated with disposing of products that can no longer be sold due to spoilage. Since it takes more refrigeration to keep products in open cases at their optimal temperature, there is often a tendency to “overcool” these cases to protect against spoilage. This can lead to even higher energy use and increased operating costs. Adding doors to open cases has been proven to maintain steadier temperatures. A recent study found that “temperature variations were significantly minimized” in open cases that had been retrofitted with doors. In addition, display cases with doors allow food products to stay safe in the event of a power outage, since the refrigerated air is kept inside rather than dissipating into the store.

One of the advantages of retrofits over replacements is the cost. Retrofitting existing open cases with doors can be done at half the cost of purchasing new doored cases, even when installation and labor are factored in. The lower cost of retrofitting means that store owners will not only avoid the capital expenditure required for new equipment, they will also see a much faster return on their investment through immediate energy cost savings. Retrofits can also help bring older open cases back to life. The added doors can give cases the fresh look of brand-new equipment without the extra cost of actually buying it.

Maintenance costs can be lowered for the refrigeration equipment in open cases that are retrofitted with doors. Compressors and fan motors need to operate less often and for shorter intervals when doors are in place to keep cool air in and warm, humid air out. These reduced run times translate into longer lifespans for these components and needing routine maintenance less frequently, letting you save on both equipment and labor costs.

Finally, retrofitting open cases shouldn’t be viewed as a one-off proposition. It’s an opportunity for store owners to take stock of all their refrigeration equipment to identify other energy-efficiency measures that can be implemented quickly and easily. For example, a case door retrofit may present the chance to upgrade the unit’s lighting to energy-saving LEDs. Not only do LEDs use up to 70% less energy than standard lighting, they also emit very little heat. That means that the case’s refrigeration equipment isn’t using power to fight the heat produced by its lighting.

While adding doors to open cases can provide all of the above benefits, there are several important factors to keep in mind before moving forward with a retrofit project:

  • Aisle width: Stores with narrow aisles, like small grocery or convenience stores, need to be aware of the size and type of doors they install so that opening a door doesn’t block customer traffic.
  • System modifications: Cutting the heat load up to 80% by adding doors means that modifications may be needed to the refrigeration system to correct the imbalance between the newly reduced heat load and the system’s capacity.
  • Fan Power: The configuration of the fan motor may need adjustment to ensure proper airflow in a case that will now be enclosed instead of open.
  • Anti-sweat heaters: Depending on the type of door installed, anti-sweat heaters may be needed to keep condensation from forming on products in the case.

Having Ecology Action as your partner in an open case retrofit can make the project so much easier and maximize the benefits. Our turnkey solutions begin by analyzing your store’s specific needs and taking you through the planning, design, procurement, and installation. Contact Ecology Action today to get started.