Located inside Studley Campus’ Central Services Building is Dal’s central heating and cooling plant. It services all three of the university’s Halifax campuses through a network of underground tunnels and pipes, and has been in operation for more than 40 years.
“It’s worked well for us, even as we expanded the university with new buildings and the addition of Sexton Campus, but it’s at the end of its service life and running at 96 per cent capacity at the moment,” explains Ken Burt, vice-president finance and administration. “It needs to be replaced.”
One option on the table is to simply replace the existing boiler technology. But the university is also considering another approach: generating its own electricity, and using the waste heat for heating and cooling.
“What we’ve been exploring is what’s sometimes called a tri-generation (“tri-gen”) system, as part of our ongoing efforts to provide cleaner energy to campus,” explains Burt.
In such a system, combustion turbine generators, fired by natural gas, would generate electricity for the Halifax campuses, and the heat byproduct would then heat and cool the buildings. (The cooling would be done through either absorption or steam-driven chillers.)
In November of last year, Dal’s Board of Governors commissioned a detailed feasibility study for such a system. The study found that the proposed clean energy system could meet all of the Halifax campuses’ electrical, heating and cooling needs, with excess electricity available at times to export into the province’s power grid.
Cost and greenhouse gas savings
One reason for Dalhousie to consider generating its own power is long-term cost savings. The university currently purchases $7.5 million of electricity from Nova Scotia Power each year for its Halifax campuses, in addition to maintenance costs for heating and cooling. While the upfront cost of a tri-gen system is greater (estimated at about $88 million versus $48 million to simply upgrade the existing equipment), it would be financed by future energy savings, with the study finding it would pay for itself and then some over a 20-30 year period.
Not only would the system be more efficient, but Dalhousie would see a significant reduction in its greenhouse gas (GHG) emissions. By generating its own electricity using natural gas and using waste heat for heating and cooling, it’s estimated Dalhousie could cut GHG emissions by approximately 16,100 tonnes per year — an almost 25 per cent reduction from the amount emitted by the current system.
“The trigeneration project would be a major energy efficiency initiative, saving total systems energy equivalent to all the energy used by residential homes in the Town of Antigonish annually,” says Rochelle Owen, director of sustainability at Dal. The proposal would help Dal reach the emissions targets outlined in the university's 2010 Climate Change Plan (a 20 per cent reduction by 2016 and a 50 per cent reduction by 2021 from the 2008-09 baseline.)
One other benefit is that Dalhousie would be able to power Studley Campus on its own in the event of a significant power outage, and therefore could act as an Emergency Response Centre for the city during situations like major hurricanes or storms.
Weighing the options
Dalhousie would be the first university in Atlantic Canada to generate its own electricity, but it would be following in the footsteps of many other schools across Canada and the U.S., including UBC, the University of Toronto, Guelph, Queens, and the Universities of Calgary and Alberta.
As for logistics, the turbines would be installed at the same site as the existing plant in the Central Services Building, with a design requirement that the plant would have to be as quiet, or quieter, than the current system
Still, the higher price tag and the increased complexity of such an approach means a final decision is still a bit of a ways off. Dalhousie is currently in discussions with Nova Scotia Power over the details of the project. (In case you’re curious, Dal accounts for less than one per cent of the province’s current energy consumption.)
The final project would only move forward with the approval of the Board of Governors; the administration is hoping to table a formal recommendation to the Board sometime this fall. Burt says that timeline is crucial to begin work on the project in the new year, whatever form it takes.
“We need to upgrade our central heating and cooling plant to meet our campuses’ needs, and we want to do so in a way that saves costs and helps meet our sustainability objectives,” he says. “With those parameters, generating our own electricity may be our strongest option.”