INNOVATION November-December 2016

f ea t u r e s

We looked at various options, such as condensing boilers, which is typically considered best practice in retrofit applications. In the end, we recommended a much more creative route. Now, Vancity’s data centre is the boiler.” As is typical of most data centres, Vancity’s third-floor hub had its own cooling system that was separate from the rest of the building. It vented waste heat from the data centre’s servers out the top of the building. SES Consulting saw an opportunity to capture and re-use that waste heat and suggested Vancity invest in a new chiller with a heat-reclaim option. The new chiller would, the company calculated, produce enough heat to warm the entire building whenever the temperature is above 5°C outside—most of the time in Vancouver’s mild climate. The existing boilers would then become backup devices, called upon only to top-up the heat delivered by the data centre through the heat recovery chiller on exceptionally cold days. Heat recovery systems of this kind are often used in new high-performance buildings but rarely, if ever, in retrofits—“and for good reason,” says SES Energy Efficiency Engineer Chris Goodchild, P.Eng. “It can be very difficult to install a chiller like this in an existing tower, especially one like this, in a busy area like downtown Vancouver.” Not only did the 2.5-tonne chiller have to be hoisted onto the roof of the 12-storey Vancity tower,

it then had to be squeezed through an 81-centimetre doorway (with just centimetres to spare)—all in the dead of night, because the SkyTrain line runs through the building on the second floor. “We couldn’t risk raising the chiller during the day in such a high-pedestrian and high-traffic area,” Goodchild says. “And TransLink will not let you lift anything above it at any time while the SkyTrain is running. With just a small window of time available, we set up a crane at about 1:00 am on a Sunday and finished just before the SkyTrain started again at 5:00 am.” The chiller was then connected to the water-heating loop coming from the existing boilers, and the new heat recovery system took over long before the first workers arrived on Monday morning. Few, if any, building occupants noticed the installation, nor were they aware of other changes to their work environment, which is exactly what SES was hoping for. “The prevailing opinion is that energy retrofits are disruptive,” Goodchild says. “This project proved that they don’t have to be.” It also proved that breaking from tradition can be good. “The tradition has been to oversize boilers and keep water temperatures very high,” Sinclair says. “We thought there was an opportunity for innovation here and did a study to show that the systems could be operated at a far lower temperature.”

Award-winning Sustainability

The Vancity Heat Reclaim project demonstrates that retrofits of existing large buildings can reduce emitted greenhouse gases below the levels specified by the Intergovernmental Panel on Climate Change, and shows that those retrofits can provide financial returns for building owners without sacrificing occupant comfort. With the project exhibiting sustainable practices and exemplifying APEGBC’s sustainability guidelines in a way that has potential to positively influence the building- construction and -maintenance industry for years to come, the Vancity Heat Reclaim Project, represented here by SES Consulting President Scott Sinclair, P.Eng. (l eft ), was awarded APEGBC’s 2016 Sustainability Award .

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