Introduction

Companies today are constantly on the lookout for innovative solutions to minimize both; their overheads and their carbon footprint. New advancements in chiller technology are just the answer to this. Some of these energy-saving components can even be retrofitted to old chiller systems, so you not only save on energy consumption and maintenance costs but also your initial investment. However, such upgrades have still not been embraced by the market due to the challenges of understanding the systems available and how they match your building’s cooling needs. Calculating returns on these systems is also challenging and a true picture can only be seen clearly after upgrading your existing system. But, thanks to one of the pioneering energy engineering company in Sri Lanka, Access Energy Solutions, in collaboration with Asiri Central Hospital, we have a benchmark of how much can be saved per month with such a system upgrade. Particularly, in a building with a highly varying occupancy in our hot and humid climate.

The hospital offers a variety of critical care services ^(P2)

Site details

The chiller system upgrade at Asiri Central covers a total area of 33,000m². The building consists of 12 floors and the cooling load for each varies with occupancy. There are two floors in particular that experience a high variance in occupancy and therefore, cooling load - the third floor which requires at maximum 3000m² of cooling tonnage, and the second floor which requires 2500m². In addition, specific areas, such as the Intensive Care Unit, require continuous cooling. Further, due to the establishment being a hospital, noise levels were also a concern that had to be addressed.

The chiller room at Asiri Central Hospital ^(P3)

Technology utilized

The upgrade from the existing system involved replacing the main chiller unit with a Variable Frequency Drive (VFD) rotary compressor Daikin chiller. Given the requirement for low noise on the hospital premises, the model selected was ensured to be one of the quietest designs in the cooling industry, thereby saving on the cost of silencing accessories. In addition to upgrading the chiller, the water pumps were upgraded to VFD water pumps, and the air handling units were upgraded with intelligent electronics on floors which experienced a high variance in their occupancy and cooling load.

Installed electronic panels to optimize energy consumption. Find out more here ^(P4)

Investment and returns

The total cost of all the above upgrades to the chiller system was in the region of Rs. 70 million. However, the energy reduction in the hospital’s monthly air conditioning bill was approximately 40%. This results in an impressive monthly saving of Rs. 2.5 to 3 million, giving the company a payback period of 2.2 years, and a Return On Investment (ROI) of 46% in the first year, which has already been realised. This makes it evident that upgrading commercial and industrial chillers is an attractive proposition for any company. These savings do not include the reduction in maintenance costs experienced, thanks to the upgrade, as highlighted below.

A BMS provides easy access to key information on the system’s health ^(P5)

Monitoring and Controlling System

The system was connected to a Building Management System (BMS) which utilised sensors at each point of the chiller system to monitor its health. This allows system engineers to centrally monitor and identify issues before they impact operations, helping the hospital reduce their energy and maintenance costs. These additional reductions add to the installation’s overall cost efficiency. And although these benefits have not been added to the above returns, they cannot be ignored and make upgrading your chiller system a very attractive investment indeed.

A consistent temperature for a warm reception, energy efficiently. ^(P6)

Conclusion

Considering the advantages in upgrading your chiller system both monetarily and environmentally, as was the case with Asiri Central, it emerges resoundingly as one of the best ways to go green. How do you find out if it’s time you upgraded your chiller system? Click here to find which questions to ask.