Cagliari - Italy
International airport
Packaged System, VRF, Mini-VRF, Zephir3
Year 2014-2019



Energy savings of around 40% compared to the existing plant
Packaged system for terminals and common areas
Dedicated systems for other areas
Year 2014-2019

Opened in 1937 and named after Mario Mameli, Cagliari-Elmas, the airport has been extended over the years and today is the most important airport in Sardinia both in terms of traffic volumes and size, with direct scheduled flights to the main European destinations. In 2018 the passenger traffic amounted to 4.355.351 people, while the aircraft traffic reached 31.371 movements.
Since 1992 it has been managed by the Cagliari Airport Management Company S.p.A. (So.G.Aer.), a group extremely focused on the environmental aspects.

Cagliari ELMAS Airport Air Conditioning System - building

The building

A total area of 200,000 m2 over 3 floors.
The ground floor is dedicated to national and international arrivals. In this area there are some services such as ATMs, bars, and the emergency room. In the baggage reclaim area, there are also the baggage assistance offices, the Customs Office and the Guardia di Finanza. On the first floor is the departures area with 42 check-in desks, airline ticket offices, a cellophane wrapping service and several refreshment points, as well as a wide range of shops. In this area are located the VIP room, the friend room, the pharmacy and the chapel. In the dock area there are other refreshment points and shops. 
On the third level there are the offices of the State Bodies, of the airlines and of the handlers, a restaurant and a modern business center with two conference rooms.

The challenge

Since 2016 Cagliari Airport management company (So.G.Aer.) has been participating in the ‘Airport Carbon Accreditation’, an independent and voluntary program that aims at the progressive reduction of CO2 emissions in airports.

At the investors request, the scope of the refurbishment project was to improve the efficiency of the airport and subsequently its environmental sustainability. This was over several phases from 2014 to 2019.

The new solution had to ensure the comfort of passengers, operators and tenants of the commercial areas of the terminal, comfort had been undermined by the continuous "failure" of the old air-water system with consequent discomfort in entire areas of the terminal when the air conditioning was not working.

The new system also had to guarantee an economic management saving compared to the existing one (water cooled with water serving the HAU at 7/12°C), which was obliged to use the refrigeration units at maximum power to reduce the latent heat, with enormous energy costs.

The solution adopted had to guarantee a single source supplier this also helped for maintenance in order to avoid the maintenance problems of the old system where parts were sources form several different suppliers.

The investment had to have a reduced ROI time and the replacement of the existing air conditioning systems had to be quick and easy to install.

Cagliari ELMAS Airport Air Conditioning System - Packaged units

The solution

The old air to water system consisting of centrifugal chillers, storage tanks, pumping units and air handling units, has been replaced by high efficiency packaged rooftop heat pumps, which heat, condition, renew and purify the air. The terminals and common areas of the terminal are served by ClivetPack2 rooftop heat pumps with dual refrigerant circuits and modular scroll compressors. For continuous capacity contol to the actual energy demand, a ventilating section with plug-in technology electronically controls the fan for finer adjustment. The new “Thor” thermodynamic recovery technology, which increases the energy recovered, thus improving the overall efficiency of the units. The units also have Electrostatic filters active on fine dust, viruses, bacteria, also fitted are air quality probes to control the percentage of CO2. This varies the flow rate of the Fresh air according to the concentration indoor CO2 levels measured. They are managed by the Multiplex supervision system with wireless TCP / IP protocol control.
The comfort system is completed with different VRF M5 and miniVRF systems serving the Arrivals Gates and the VIP Lounges: all equipped with inverter technology for maximum efficiency.
The air renewal in the commercial terminal and the terminal where the offices are located is entrusted to the packaged ZEPHIR3 units, which integrate the entire air renewal system in a single autonomous unit with thermodynamic energy recovery, simplifying the plant and reducing even 50% primary energy consumption compared to UTA + chiller solutions.
The plant layout is completed by high efficiency WSAN-XSC3 type Chillers, which produce cold water for some applications related to the use of CF type fan coils, all with Clivet Talk electronics and wired on MODBUS supervision systems.

The results

The new system guarantees year-round comfort with an energy saving declared by SOGAER SPA's energy manager of about 40% compared to the existing system, with a satisfactory payback, which after a few years guarantees the return of the investment for over 1.4 million euros.
The packaged system that integrates all the components and leaves the factory already tested in all its functions, has been installed directly by the internal maintenance team of the investor. For the installation it was only necessary to adapt the pre-existing channels to the new machines by an external company.
The units, equipped with a CO2 probe, adapt the operation to the real need for air exchange in the rooms, guaranteeing 360-degree comfort, energy and money savings.
The air distribution takes place through steel ducts equipped with jet induction nozzles suitable for large heights, as well as with air handling terminal units ideal for installations where it is necessary to create an air distribution through ducts.
Energy savings are also guaranteed by the inverter technology that features VRF and mini VRF Clivet systems at the service of some gates and VIP lounges, and the innovative ZEPHIR3 air purification system with thermodynamic recovery for offices and areas dedicated with which were substituted elements enslaved to refrigerator groups and full fresh air AHU.
Even the undeclared objective of having a single interlocutor in order to facilitate assistance was achieved thanks to the wide Clivet offer able to satisfy the various plant requirements with dedicated systems.

Elmas airport view with Clivet rooftops

Clivet system

  • 27 rooftop Clivetpack2 (CSRN-XHE2 and CSNX-XHE2)
  • 12 ELFODuct air handling terminal units, ideal for installations with air distribution through ducts
  • 1 P-Matic rooftop supervision system
  • 2 ZEPHIR3 air renewal and purification systems in the offices area and international arrivals gate terminal
  • 1 VRF system: outdoor unit M5-XMI 50T + 5 indoor Q4DN-XMI units (international arrivals gate terminal)
  • 2 Mini VRF systems: external unit MSAN-XMI 140M + 4 indoor units Q4AN-XMID36; outdoor unit MSAN-XMI 260M + 2 indoor units CN-XMID90 (Crew lounge and Sala VIP Amica)

Cagliari ELMAS internal view

The team

  • Designer of the energy and functional feasibility study: Ing. Alessandro Campus Thermes
  • Executive designer: Ing. Massimo Rodriguez of SO.G.AER. Spa
  • Investor and installer: SO.G.AER. Spa
  • Clivet agency: Elettric Commerciale Sarda - Sestu, Cagliari - Italy