Retrofitting Keppel Bay Tower for a Zero Energy future

In 2018, Keppel Land leveraged a grant from the Building and Construction Authority of Singapore Government (BCA) under the Green Buildings Innovation Cluster (GBIC) Programme to implement and test new energy efficient technologies at Keppel Bay Tower to reduce the building’s energy consumption. The tower had already achieved the BCA Green Mark Platinum status but the aim of the GBIC initiative was to reduce energy consumption by a further 20%.

Danfoss, along with long-term partner NOVENCO, proposed retrofitting an existing centrifugal fan in one of the building’s air handling units (AHU) with the high efficiency EC+ concept engineered to boost the efficiency of HVAC systems in both new-build AHUs and in existing systems.

The Danfoss-NOVENCO EC+ concept proposal, which leverages the high efficiencies and integration ease of VLT® HVAC Drive FC 102, motor, and ZerAx® fans, was reviewed by industry experts appointed by the BCA and independent researchers. They could clearly see energy reduction potential in the EC+ concept combining some of the most innovative technologies in the market — while offering an easy retrofit to minimize downtime and inconvenience.

As one of five technologies chosen for the GBIC initiative, the EC+ concept enables significant reduction of energy use in AHUs by means of three components: intelligent Danfoss VLT® drives, NOVENCO’s highly efficient ZerAx® axial flow fans, and IE4 and IE5 permanent magnet (PM) motors.

The concept is characterized by two key factors — namely the high efficiency of each of the individual components as well as their intelligent interaction. The result is a seamless, fully compatible solution that enables realization of its full potential delivering optimum system efficiency. Also, the EC+ concept offers a low-risk solution by utilizing only time-tested, proven technologies.

Unlike the centrifugal fan, axial fans utilize both the static and the dynamic pressures. The ZerAx® fan is therefore more efficient, consumes less energy, reduces operating costs, and lowers carbon emissions — plus, it reduced the sound level significantly.

Variable speed drives enable energy efficient application control, which makes them key to achieving energy savings in building operations. A HVAC-dedicated drive with built-in intelligence, the Danfoss VLT® HVAC Drive FC 102 is known for its high reliability, low total cost of ownership (TCO), and many application functions. This made it the perfect match for Keppel Bay Tower as a modern building fitted with a wealth of sophisticated solutions.

The retrofit — done in January 2019 — was completed in less than 10 hours.

The EC+ AHU retrofit delivered energy savings of more than 45% for Keppel Bay Tower — as well as a more pleasant environment for the building occupants thanks to the lower sound level. This result played a significant part in the 22.3% reduction in the building’s annual energy consumption as of February 2020 — exceeding its initial target of 20%.

Recognizing the company’s efforts, Keppel Bay Tower was therefore certified by the BCA as a Green Mark Platinum Zero Energy building — the first commercial building of its kind in Singapore. And its new high efficiency air distribution system based on the EC+ concept was one of the key contributors to this achievement.

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