An HVAC (Heating, Ventilation, and Air Conditioning) system is essential for maintaining comfortable indoor environments by controlling temperature, humidity, and air quality. Bagatelle Mall has recently taken a major step toward environmental sustainability by upgrading its HVAC system with an innovative chilled water network that now spans the entire mall. 

1. What type of refrigerant gas is currently used in the chiller system at Bagatelle Mall?

Bagatelle Mall has taken a significant step towards environmental sustainability by upgrading its HVAC system with a new chilled water network that extends throughout the entire mall. This advanced cooling system is powered by state-of-the-art chillers, utilising a next-generation refrigerant known as R1234ze. Classified as a Hydrofluoroolefin (HFO), R1234ze is a vast improvement over traditional refrigerants like R134a, commonly found in similar chiller applications in Mauritius.

R1234ze offers multiple environmental benefits, including optimised energy efficiency and reduced electricity consumption. More importantly, it is eco-friendly, as it neither contributes to global warming nor depletes the ozone layer. This transition reflects Ascencia’s commitment to embracing innovative and sustainable technologies in its operations, marking a major milestone in its ongoing efforts to protect the environment. This project is among the first in Mauritius to use this environmentally responsible refrigerant, setting a new standard for eco-conscious practices in the country.

2. Is the refrigerant gas available in Mauritius?

Although available locally, R1234ze is not as widely accessible as more common hydrofluorocarbon (HFC) refrigerants like R134a. These  HFCs were introduced as a replacement for chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), which were phased out due to their harmful effects on the ozone layer.

Despite being ozone-friendly, HFCs have, however, a relatively high global warming potential (GWP) and Authorities have an implementation plan to phase them out. The availability of R1234ze is therefore expected to improve as it has been highlighted as a key alternative due to its low global warming potential

3. Are there any challenges associated with the gas availability or procurement?

Yes, as there is a significant demand for R1234ze globally. This is driven by rising awareness of climate change and stricter regulations surrounding greenhouse gas emissions which are pushing industries to adopt more sustainable refrigerants.

Another challenge arises from the fact that refrigerants are categorised as 'hazardous goods' in maritime shipping which require stringent safety measures during transport to minimise the risk of hazards and the process of shipping refrigerants can be quite lengthy.

To ensure uninterrupted operations we keep a buffer stock of the refrigerant.

4. Explain the characteristics of the refrigerant gas R1234ze with regards to the protection of the environment

R1234ze is considered better for the environment for the following reasons:

• It has a Low Global Warming Potential (GWP)- Unlike traditional refrigerants like R134a, which has a high GWP, R1234ze has a very low GWP (less than 1). This means it has a minimal impact on climate change, significantly reducing its contribution to global warming.
• Zero Ozone Depletion Potential (ODP)- R1234ze does not contain chlorine, so it doesn’t deplete the ozone layer,

• Energy Efficiency - R1234ze enhances energy efficiency in cooling systems through its favourable thermodynamic properties that improve heat transfer, allowing for effective cooling with less energy. It operates at lower pressures than traditional refrigerants like R134a, reducing the workload on energy-intensive compressors and thus decreasing overall energy consumption. Additionally, modern chillers designed for R1234ze incorporate advanced technologies that optimise performance and further lower energy use.

5. Are there any environmental regulations in Mauritius that influenced the choice of gas in the chiller system, and how does Ecoasis ensure compliance with these regulations?

Mauritius has demonstrated a strong commitment to the Montreal Protocol and its Kigali Amendment, actively participating in efforts to protect the ozone layer and address climate change.

While the Montreal Protocol focused on phasing out substances that deplete the ozone layer (like chlorofluorocarbons, CFCs), the Kigali Amendment aims to phase out hydrofluorocarbons (HFCs) as they have high global warming potential and contribute to climate change.

Mauritius has successfully phased out the use of CFCs and the next step is to phase out HFCs. The Ministry of Environment, Solid Waste Management and Climate Change has a Hydrofluorocarbons (HFCs) Phase Down Management Plan with a commitment to cut down the production and consumption of HFCs by more than 80% over the next 30 years.

Ecoasis wants to position itself as a responsible participant in national efforts to combat climate change and protect the environment. We have thus adopted a proactive strategy by proposing the refrigerant R1234ze (low GDP) to our clients in anticipation to revised policies regarding the use of HFCs.

6. With the global push towards sustainability, are there plans to upgrade the chiller system to use even more environmentally friendly gases or technologies in the near future?

To align with the global trend towards sustainability and reducing the carbon footprint of cooling systems, natural refrigerants like propane are being adopted. Whilst the chiller system at Bagatelle Mall can potentially be upgraded to use propane, it is a process that would require modification or replacement of the chiller's components, such as compressors and expansion devices to ensure compatibility with the characteristics of the gas.  This change in the refrigerant is not currently planned for the chillers at Bagatelle Mall, but it is something we aim to explore for future installations.

To further minimise the carbon footprint of Bagatelle Mall’s HVAC system and enhance energy efficiency, we are actively considering the integration of a photovoltaic system. This solution would allow us to harness solar power to supply a part of the electricity needed for the chiller system. This initiative would not only cut down on electricity consumption but will also contribute to broader sustainability goals, reinforcing Ascencia’s commitment to environmentally responsible operations and long-term energy cost savings.

7. How does the operational and maintenance cost of the current chiller system compare to other systems that use different gases?

Adopting R1234ze in cooling systems helps optimise energy consumption because its thermodynamic properties allow absorption and release of heat more effectively, requiring less energy to maintain desired cooling levels. The refrigerant also operates at lower pressures compared to traditional refrigerants like R134a which reduces the workload on compressors, which are energy-intensive components in HVAC systems. As a result, less energy is consumed during the cooling process. Operating at lower pressure also puts less stress on the system components reducing wear and tear and leading to lower maintenance costs over time.

Also, modern chillers and cooling systems, designed to work with R1234ze are often equipped with advanced technologies that improve system monitoring and control which allow predictive maintenance, helping prevent costly breakdowns or downtime by addressing issues before they become severe, further enhancing efficiency.