Biddle provides sustainable climate solutions to Delhaize

Delhaize, a Belgian retailer, can be described as a true pioneer in environmental and climate protection. In May 2019, the company announced an ambitious sustainability program to improve its environmental impact. 


Delhaize Sustainability Program

With this Sustainability Program, Delhaize had three main objectives:

  1. To reduce the use of plastics,
  2. To reduce food waste and
  3. To achieve carbon neutrality by 2021.

CO2 emissions have been reduced by 44% since 2008, the lighting has been completely converted to LED since 2014 and two-thirds of the shops have been equipped with refrigeration systems, using natural refrigerants. In 2018, new solar modules, with a total area of 4000m², were also installed and a program, designed to encourage employees to switch to bicycles and e-bikes, has resulted in total annual savings of 515 tonnes of CO2.

A very impressive, but by no means final result.

The sustainability actions of Delhaize include the use of “state-of-the-art” air-conditioning technology. In 2016, for example, the company opened its first supermarket in Denderleeuw, Flanders, with a "CO2 refrigeration system with heat recovery".

CO2 is a naturally occurring gas that is perfect for use in refrigerated cabinets in showrooms and cold stores. In addition, it allows the transfer between hot and cold air waste, generated by cold or hot water, which in turn can be used as a completely harmless medium for indoor air conditioning, both in the social areas and storage rooms of the supermarket.


The Requirements

Delhaize required supply temperatures of 45°C to 50°C for heating and 7°C for cooling have been achieved by Biddle’s efficient, low-temperature devices. Biddle installed technically mature and energy-efficient air curtains and Comfort Circle Cassette Units in the store.

With the CC cassettes, the heating function was in the foreground due to the relatively limited temperature range available. With a focus on sufficient flow temperatures, it was decided to use water-heated SR air curtains.

Delhaize has not only improved its environmental performance by eliminating CFC-containing refrigerants, but also through energy-saving heat recovery.

The Solution

Open doors are inviting and increases customer frequency and sales. But how is this compatible with the sustainability concept of Delhaize? Do open doors not automatically mean high energy losses?

The solution is called "climate separation". 

An air curtain ensures that in the cold season, the warm indoor air does not escape and no cold air from the outside penetrates into the shop. The opposite can be done during spring and summer: the hot, possibly even humid, outside air stays outside, while the store is consistently and pleasantly cool. Dust and insects are also prevented from entering.

In addition, the customer feels the (depending on the season) warming or cooling airflow as pleasant. As soon as you enter the shop, the unobtrusive air curtain gives the customer a feeling of comfort. The key to this climate solution, when designed correctly, is that it is more energy efficient, compared to an entrance with automatic sliding doors which remain open at peak times anyway.

An inviting environment thanks to energy efficient climate separation

This energy efficiency is achieved by integrating Biddle’s SR air curtain into an existing hot water heating system, requiring minimal installation effort. Another variant is combining it with a heat pump or, as in Denderleeuw, integrating it into a heat recovery system right from the start. In all three options, the hot water is passed through a water register in the air curtain, where it heats the intake air to 35°C before blowing it out. As a rule, a flow temperature of just 45°C is sufficient for this purpose. For about 80% of the year in Belgium, these temperatures are sufficient. In the few weeks, during which the thermometer falls below the zero-degree mark during the day, the Hybrid version of the SR can be electrically heated as required.

In this air curtain, the hot water coil is supplemented by an electric heating element. When the automatic air curtain control detects that the required room temperatures are not reached, the electric heating elements switch on and generate additional heat to cover the temperature requirement. The cabling effort to install the control is minimal. In purely water-heated models, the flow temperature of the hot water can be increased for a short period of time by a gas boiler or a heat pump. So even in extreme weather, a consistently pleasant room climate is guaranteed.

In fact, the flow temperatures in the Denderleeuw heat recovery system were found to be somewhat low over time, so it was finally decided to use the SR Hybrid air curtain to compensate for the extreme outside temperatures.

An air curtain with high-depth-effect also means that unpleasant drafts are avoided - especially in the supermarket cashier area, where not only customers stay longer, but also employees.

The automatic control means that the staff won’t unnecessarily increase the blow-off temperature if they find the airflow too cool or not warm enough. Although the air curtain can be also controlled locally, using the intelligent b-touch touch-screen control panel, the central control and the b-connect monitoring module (or the integration in an existing building control system) makes much more sense.


Smart Innovations for a comfortable climate

What sounds so simple, requires a high degree of technical know-how and clever innovation. The SR air curtain combines four innovative technologies that enable Delhaize to save a lot of energy:

  • i-sense

    The patented i-sense infrared sensor, which continuously monitors the interior and exterior door opening temperatures and counts the customers entering or leaving the store.


    Based on the i-sense data, the sophisticated Corrective Heating and Impulse Prediction System (CHIPS), automatically calculates the right outlet temperature, the required airflow outlet width and the blow-off speed, ensuring that the air curtain actually reaches the floor.

  • Controlled Air Strength

    The changes are then implemented by the Controlled Air Strength technology, which automatically adjusts the outlet cross-section of the outlet grille to the respective fan speed 

  • Rectifier

    The patented Rectifier then turns the air turbulence generated in the fan into a nearly laminar air flow.

Complete Climate System

The same principle is behind the design of the Comfort Circle Cassette units, which can be installed to save space and be unobtrusive in suspended ceiling systems or as free-hanging models with appropriate cladding.

The room air to be heated or cooled is sucked through an elegantly-designed, round, perforated grille on the underside of the device, unlike conventional recirculation units, where it is blown out again by the same grid.  

As with the SR, the air is conditioned by a water heat exchanger that uses the waste heat from the supermarket's CO2 refrigeration systems. The conditioned air is then blown out via the outlet opening, running in a ring around the intake grille, which gives the name of the entire cassette system. This adjustable air guide ensures that the conditioned air is distributed optimally and evenly throughout the room. Thus, a good depth-effect and air circulation are achieved even at a low blow-out speed.

For optimum depth, the heaters blow warm air at an angle of 45° in the direction of the floor and the refrigerators blow out the cold air horizontally along the ceiling. This use achieves the Coandă effect for an optimal, draft-free distribution throughout the room.

The unobtrusive, yet elegant, appearance of the Comfort Circle air conditioning cassette makes it the ideal solution for all rooms and gives the customer an undisturbed feel-good experience. 


Reliable Partner

Combining the Comfort Circle Cassette unit with the SR Air Curtain, Delhaize has an ideal solution for optimising energy-efficient climate comfort. In cooperation with Delhaize and in particular with the successful implementation of the Denderleeuw project, Biddle once again proved to be a competent, innovative and reliable partner in the development, planning and implementation of energy-efficient complete climate solutions for the environmentally-conscious and sustainable retail sector.

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