Supermarket Fridge Doors: There is an Alternative (Part 3)
In our previous two blogs, we examined:
The articles showed how supermarket refrigeration doors do not save as much energy as claimed and how the total lifetime costs are much higher than most retailers realise.
However, if fridge doors are not the answer, what is?
Before we look at supermarket fridge door alternatives, it is important to recap why energy savings from supermarket doors are not as straightforward as they first appear.
One of the reasons doors underperform is the Bellows Effect. Each time a hinged door is opened, cold air is dragged out (by the door) and warm air is drawn back in. As supermarket fridge doors are opened hundreds of times per day by shoppers and staff, this effect happens constantly. The more the doors are opened, the less energy they can save.
CFD (Computational Fluid Dynamics) allows us to measure the bellows effect, and shows why claims of singular, fixed energy savings are misleading and frequently overstated. Energy performance is transient because door openings are transient.
How CFD transformed supermarket fridge design
In 2019, Aerofoil Energy, working with Williams Advanced Engineering, began a research project to design and build a super-efficient open-front fridge - without doors.
Our prototype cabinet was shown to be 54% more energy efficient than an equivalent open fridge, and 27% more energy efficient than an equivalent doored fridge.
We called the prototype - the Elite Fridge.
The project proved that barrier-free, open fridges, can be designed to be even more energy efficient than fridges fitted with doors.
CFD Design & Analysis
Prototype Build & Testing Phase
A new technology that doesn’t compromise the customer journey
Following the project, the Aerofoil Team spent several years refining the concepts from the Elite fridge and adapting them into a technology package that can be used in any fridge cabinet.
We named the new technology Invisidoor.
Invisidoor can be retrofitted to fridges in stores or integrated by manufacturers into new cabinets at the point of build. We chose the name because it is not a door at all, but a more advanced, modern solution for fresh-food retailing - without barriers.
There are two pathways:
#1. Invisidoor (retrofit):
Invisidoor can be retrofitted to fridges in stores in just minutes, with no need to empty food or turn fridges off. Energy savings are comparable to retrofitting doors, but at a fraction of the cost. Crucially, Invisidoor is barrier-free, maintenance-free, and requires no additional cleaning or operational changes.
#2. Invisidoor (new cabinets):
Designed to be integrated by cabinet manufacturers at the point of build (OEM integration of CFD optimised airflow). The result is that new fridge cabinets arrive fully optimised, saving as much or more energy than doors, again at a fraction of the cost and without barriers.
Invisidoor benefits
These CFD-led solutions give retailers a unique combination of technical and commercial advantages:
Barrier-free, customer-friendly shopping. Shoppers can see and reach products more easily, without being put off by doors or handles.
Operational simplicity. Store teams do not need to manage door maintenance, cleaning, or operational disruptions.
Maintenance-free technology. Invisidoor has no moving parts, electrical components, or servicing requirements.
Hygienic design. No customer touch points and fewer surfaces for germs or smears.
Low-cost, no recurring overhead. Invisidoor costs significantly less than doors to fit, and adds no extra ongoing expenses.
Exceptional ROI. Energy savings are delivered at lower upfront and long-term cost, so payback is rapid and predictable.
Future-ready. Solutions can be scaled across existing estates (retrofit) or embedded into new cabinet purchases (OEM integration).
Today
Invisidoor – Optimised cabinet designs have now been completed with three major manufacturers in Europe and are in process in the USA.
Invisidoor – Already retrofitted by three leading UK supermarkets, with installations scheduled across Europe and the USA by October 2025.
These solutions are no longer experimental: they are already proven, adopted, and being rolled out at scale.
Proof from leading retailers
Prior to launching Invisidoor, our existing supermarket energy technologies (Aerofoils) have already delivered results across some of the world’s largest supermarket groups:
Sainsbury’s saw a 15% reduction in energy created from fridges across its estate after rolling out Aerofoils nationwide.
Tesco continues to work with Aerofoil on advanced airflow technologies, building on estate-wide deployment to further enhance performance.
Marks & Spencer adopted Aerofoil technology across its UK stores, highlighting how improved cabinet temperatures contribute to a better customer experience and reduced energy use.
ASDA reported a 17% reduction in refrigeration energy use across 187 stores fitted with Aerofoils, helping to meet its 2025 carbon goals.
Invisidoor builds on the capabilities of Aerofoil technology, delivering even higher energy savings and a real alternative to fridge doors.
These examples clearly demonstrate the scalability, reliability, and real-world performance of aerodynamic refrigeration.
The best of both worlds
Supermarkets no longer need to compromise between energy savings and a barrier-free shopping experience. Doors were introduced to solve a problem, but their performance is undermined by the fact that they are opened constantly. CFD has shown us why, and more importantly, it has provided the pathway to something better.
By combining advanced aerodynamic design with rigorous real-world testing, Aerofoil Energy has created technologies that match and even exceed the energy performance of doors, without any of the drawbacks.
The result is that retailers can:
Cut their energy costs.
Improve food quality and reduce waste.
Provide a comfortable, barrier-free shopping environment.
Avoid the ongoing costs and complexities of maintaining doors.
With Invisidoor and Elite, supermarkets can now achieve the best of both worlds: all the energy savings of fridge doors, but from open-fronted, customer-friendly cabinets.
To learn more about barrier-free, energy-efficient cooling, contact us today