Groupe Petra - Efficiency Plan for the CIBC Tower

When a giant of the sixties needs a face lift, the constraints and costs can add up quickly. But, helped by the Énergir Recommissioning of building mechanical systems program , the CIBC Tower got a new lease on life and obtained LEED certification.

Recommissioning of mechanical systems

+ 10% in energy efficiency*
5% natural gas consumption savings per year (= 55,766 m3)
3 years for payback on the investment

Grant

$22,192

The problem with tall, slender towers

Stark and elegant, the CIBC Tower is often featured on postcards of downtown Montreal. At 225 metres in height, including antenna, it was briefly the tallest tower in Canada when it was opened in 1962. Given that it is very thin in relation to its height, this characteristic created energy efficiency problems.

“The relatively abundant fenestration and the building’s significant demands for vertical energy exchanges turned out to be major elements to be considered in our approach to optimization,” comments Alain Beaulieu, Director of Real Estate at Groupe Petra, which manages several office towers offering prestige space downtown. “The project essentially called for upgrading the tower, designed at a time when energy was not an issue, into an efficient building according to the standards of the 21st century,” adds Yan Wilscam, Operations Manager at Groupe Petra.

In 2016, Groupe Petra began a complete recommissioning of the building. “It was a colossal undertaking,” confirms Alain Beaulieu. The project aimed to reduce energy consumption, optimize comfort, and obtain LEED certification for the CIBC Tower without affecting the activities of the 45 corporate tenants.

Comfortable air

“People struggled to open the doors on the ground floor, the chimney effect was so strong in the tower,” says Jean Thibeault of Johnson Controls, which was given the mandate to recommission the mechanical systems.

Since the chimney effect is based on a natural principle that hot air rises while cold air stays on the ground, the taller the building, the stronger the chimney effect. To contend with this phenomenon, the company installed pressure gauges on various levels to modulate the air flows entering and leaving. “The goal was to obtain neutral pressure on each floor. The new system now adjusts itself automatically, according to the characteristics of the outdoor air,” explains Jean Thibeault.

First air, then water

The Johnson Controls team discovered that some pumps were idling and that the chillers were running short of water. Speed controllers were installed to maintain a good differential pressure in the chilled water system on which the server rooms, ventilation and summer air-conditioning systems depend. Lastly, a speed controller was added to the air inlet on one of the natural gas boilers: a simple idea that generated three times its initial cost in annual savings!

“These tools didn’t exist at the time it was built. All the systems had fixed flow rates with no controls,” Jean Thibeault recalls.

Nowadays, everything is controlled!

Natural gas: An efficient energy

Alain Beaulieu acknowledges that the project would not have been worthwhile without the help of Énergir. “The grant program is one of the things that allowed us to go ahead,” he reveals.

“Énergir is an excellent partner from all points of view. For us, choosing natural gas meant opting for the efficient management of our energy consumption. Also, natural gas helps reduce our environmental footprint, which is an important criterion for our tenants,” he adds.
Énergir listens to its customers first, then proposes customized solutions. If all my suppliers were like that, I’d be very happy!

Alain Beaulieu, Director of Real Estate at Groupe Petra

 * Results obtained by a combination of Énergir programs for Recommissioning of building mechanical systems and Implementation of energy efficiency measures, as well as other initiatives.