CO₂ at centre of Atlético Madrid’s new stadium

Natural refrigerants are at the heart of Atlético Madrid’s new football stadium the Wanda Metropolitano, which opened its doors in September 2017. The state-of-the-art facility, with capacity for 68,000 people, is equipped with a CO₂ transcritical system with parallel compressors and multi-ejectors. Albert Albert, in charge of the project at system manufacturer Pecomark, spoke to R744.com about the installation.

Pecomark provided the system, working in partnership with Fagos (industrial kitchen), Danfoss (ejectors), Bitzer (compressors), ECO (gas coolers and evaporators), Dinafri (commissioning) and Automatiza (electric switchboards).

The system provides cooling for a large kitchen serving different restaurants and VIP lounges. The installation features cold rooms at 0°C (fresh food) and -20°C (frozen foods), blast freezers at -30°C, and kitchen rooms at +10°C.

A CO₂ system was the preferred solution, delivering water at high temperatures and functioning effectively even when cold rooms are far away from the machinery room, in this case more than 50m.

“The heat recovery from the system is used for making hot water and heating the soccer pitch,” said Albert.

The installation serves four low-temperature units and 12 medium- and high-temperature units (three out of 12 are workrooms). The cooling capacity is 95 kW at an evaporating temperature of -10°C and 45 kW at -28°C /-30°C.

The system is designed for an ambient temperature of 38°C. “The installation can work at higher temperatures, but this is the design temperature,” said Albert.

This system relies only on CO₂. “One of the premises of the project was that if we go with CO₂, we’re going all the way with CO₂ and not with auxiliary systems that need other refrigerants,” said Albert.

Albert cited the following reasons to go for CO₂: 

• Cutting-edge technology available (parallel compression and ejectors) that allows for energy savings compared to HFCs/ HFOs.
• Heat recovery to be used in other areas
• Tax-exempt and future-proof solution
• Low carbon footprint
• To become a flagship stadium equipped with the latest technologies in refrigeration, lighting, comfort, and safety.

A comparison study with a traditional R404A system (containing theoretical data, because the system was installed too recently to show results already) shows that the CO₂ system with parallel compressors and ejectors allows for energy consumption reductions of 15%.

“The installation is running smoothly and the control of ejectors is very stable,” said Albert.