Hungary

Energy-saving Rooftop Retrofit for Auchan

The innovative Oxyma Rooftop Retrofit with Oxycom’s IntrCooll delivers energy savings, a better indoor climate, and ESG compliance.

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Summary

At the Auchan hypermarket in Soroksár (Hungary), the operations team was dealing with a familiar challenge in the retail industry: the aging rooftop HVAC units were becoming less reliable and using more energy every year. This affected employee comfort and increased the risk of fresh products spoiling, and it also caused issues with in-store equipment and systems. With ESG requirements and sustainability regulations becoming stricter, the potential for financial penalties had become a real concern.

Interviewed

Gábor Bánfalvi - Technical and Investment Director at Auchan.
Bence Arnóczki - Project Manager at Oxyma (Oxycom's partner in Hungary).

Adiabatic cooling solutions for supermarkets

About Auchan

Auchan has been active in the international retail sector for more than 50 years. With an extensive network of hypermarkets and supermarkets, it offers a wide range of food, non-food products, and services to millions of customers worldwide.

The store was facing the challenge of meeting a mandatory energy reduction target of no less than 7.78 million kWh. This forced the management team to make a difficult choice:

Purchase Energy Saving Certificates (ESC) on the market.
Accept and pay the penalties.
Or invest in a comprehensive modernization program.

After extensive research, the team chose Oxyma Systems Kft. and their groundbreaking Rooftop Retrofit solution with Oxycom’s two-stage adiabatic cooling system (IntrCooll), a system developed by experts in air and water management and specifically designed for fast and effective modernization in situations like this.

A trusted brand facing a complex challenge

The Auchan hypermarket in Soroksár is a key retail hub in one of Budapest’s busiest commercial areas. Like many older stores, the location relied on nine rooftop HVAC units for cooling, heating, and ventilation. However, these systems had long exceeded their technical lifespan. The result was rising maintenance costs, increasing breakdowns, and an indoor climate that was becoming ever harder to keep stable and comfortable.

Key challenges of the existing system:

Outdated, low-efficiency compressor-based cooling (COP 2.0–2.5).
Obsolete controls and poor thermal insulation.
Aging fans and heating coils.
Significant annual refrigerant losses. Often involving banned or phase-out HFO/HFC gases.

The challenges

The HVAC issues faced by Auchan Soroksár were typical of large-scale retail buildings still relying on outdated rooftop systems:

Inadequate performance during summer peaks

The aging rooftop units struggled to meet demand, failing to maintain the target 25°C indoor temperature.

ESG and regulatory pressures

Tightening standards around refrigerants, emissions, and energy consumption made the legacy system increasingly unsustainable.

Insufficient fresh air supply

Ventilation fell short in busy retail areas and employee work zones.

High energy costs

The system’s inefficiency translated directly into rising operational expenses.

Constant failures and maintenance

Frequent breakdowns disrupted daily operations and increased service costs.

Auchan’s choice was a Rooftop Retrofit, a state-of-the-art, future-proof solution. One that meets all the performance, comfort, and sustainability requirements without compromising the installation effort of a standard rooftop unit replacement.

The solution

Oxyma’s Rooftop Retrofit program is a unique choice in the HVAC
industry, offering a tailored suite and an energy- and cost-efficient alternative to traditional rooftop system replacements.

Given that Auchan’s facility would have required a full system swap, Oxyma’s advanced retrofit solution offered an opportunity to go beyond replacement and deliver long-term performance, sustainability, and control.

This plug-and-play system was precisely engineered to fit the store’s existing setup. It preserved the original airflow pathways, pressure zones, mounting base, and duct connections, requiring no more installation effort than a conventional rooftop unit while delivering superior performance and a future-proof outcome.

The solution has two core components:

A custom-engineered air handling unit (AHU) by Weger
An integrated IntrCooll IDEC cooling module from Oxycom, a
nature-inspired core of the system

IntrCooll Plus module

Oxycom’s revolutionary, award-winning air cooling unit based on two-stage adiabatic technology (SEER >15–30), integrated as a precooler into the AHU dramatically increases system performance and energy efficiency.

AHU module

The custom-designed air handling system for Auchan’s existing setup was manufactured in accordance with RLT and ERP Eco-Design guidelines, as well as DIN and VDI standards, and is certified by EuroVent.

On-site installation

System installation began in the spring of 2025 and took approximately three weeks while the store remained fully operational.

During commissioning, we conducted detailed airflow and temperature measurements, validated the control logic and weather-based automation, and the real-time data with projections from the initial simulation.

Initial tests confirmed that the system was delivering the forecasted results right from the start.

"Throughout the entire renovation, the store remained fully operational, without having to close for a single day. We organized the construction in a way that caused no disruption for either staff or customers. The entire upgrade took place virtually unnoticed."

Bence Arnóczki

Project Manager • Oxyma

The results

With the Rooftop Retrofit solution, which utilizes Oxycom’s two-stage adiabatic cooling system (IntrCooll), significant results have been achieved, including:

85% energy savings on cooling and ventilation (890,465 kWh per year, ≈ 3,215 GJ), approximately €182,000 per year.
43% lower fan load in winter (134,089 kWh per year, ≈ 484 GJ), approximately €24,000 per year.
365 tons less CO₂ emissions.
38% reduction in gas consumption.
70% lower solar heat load, with 13% savings on cooling energy, approximately 205 kW less radiant heat through skylights, and 191,000 kWh saved per year, roughly €45,000 per year.
40% less fruit and vegetable waste.
0% F-gas, thanks to a natural refrigerant.

Maximum impact with Oxycom's IntrCooll

25 °C

Max. internal temperature

100 %

Fresh supply air in the summer

-50 %

Airborne dust concentration

“We were looking for a comprehensive solution for the store’s climate control, and Oxyma’s Rooftop Retrofit system delivered on all fronts: low energy consumption, reduced environmental impact, and easy maintenance. The typical ‘store air’ is gone. Instead, it feels as fresh just as if we were outdoors.”

Gábor Bánfalvi

Technical and Investment Director • Auchan

Create a healthy indoor climate with massive energy savings

Oxycom is here to help. Our specialists give you free customized advice on sustainable two-stage adiabatic cooling. It’s a truly sustainable investment that empowers your facility to:

✅ Cut energy and operating costs dramatically.
✅ Meet and exceed ESG and regulatory compliance.
✅ Create a more comfortable, efficient, and healthy environment for everyone inside.

Download the case study

Let’s talk about your heat problem!

Get in touch with Oxycom and see what our adiabatic cooling can do for your factory.