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Smart investments in higher education: lighting and chiller retrofits at U of T

Comprising approximately 11 million square feet, University of Toronto’s 180-year-old campus encompasses over 120 buildings averaging 77 years of age.  When a chiller failure led  to the closure of the Ontario Institute for Studies in Education (OISE) at the University of Toronto one hot summer day in 2004, capital constraints could no longer justify deferring the replacement of the 36-year-old-unit.


December 23, 2009
By Robert Colman

Recognizing that the breakdown at OISE was a symptom of a much bigger problem, Ron Swail, Assistant Vice President, Facilities & Services and his colleague, Bruce Dodds, the department’s Director of Utilities and Building Operations, decided to re-examine the entire cooling infrastructure on the downtown campus. A comprehensive and ambitious campus-wide retrofit plan was developed. 

Challenges
The project strategically paired an essential cooling system upgrade with a major lighting retrofit. Yielding substantial energy savings and reductions in greenhouse gas emissions, the combined project aimed to maximize available incentives and external financing, rendering it both cost effective and environmentally responsible.

Environmental concerns were at issue as some of the existing light fixtures had the original electromagnetic ballasts, possibly containing polychlorinated biphenyls (PCBs). Increasingly frequent failures were also straining the maintenance budget.

“The university undertook a major lighting retrofit in the mid-1990s, during which we changed the old T-12s to T-8s, but the voltage in three of our largest buildings was not common, so the ballasts that were available for them were not tried and tested enough to replace,” notes Bruce Dodds. “A few years ago they perfected the technology for the electronic ballasts, so we have been able to retrofit the lights in all three buildings (the Medical Sciences Building, Robarts Library, and OISE) with an extremely good return on investment.”

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An audit of campus buildings and infrastructure also identified 18 chillers, some of which, like the unit at OISE, had exceeded their rated service life by 10 to 20 years. The equipment, which provided air conditioning to 21 buildings on campus, had become increasingly expensive to maintain and repair. Moreover, all of the units used R11 refrigerant, a substance containing ozone-layer-damaging chlorofluorocarbons, which posed an environmental liability.

“They stopped producing R-11 refrigerant in 1996, and it’s gradually being phased out — you are not supposed to use it past 2011,” notes Dodds. A widespread upgrade was urgently required.

Solution
U of T achieved energy savings by retrofitting and upgrading existing equipment. 

“The chillers were replaced with new high pressure equipment that runs using a different type of refrigerant, R-134A, which does not produce holes in the ozone layer,” explains Dodds.

“The other thing we did with some of the building chillers is that we interconnected certain buildings,” he continues. “For instance, our chemistry building and physics building — we took the chillers right out of those and instead put a bigger chiller in our IT centre, and then piped the chilled water to the physics and chemistry buildings. Because these are research buildings, you generally have 100% redundancy, so that if one machine breaks down you don’t lose any research. But because we concentrated all the chiller in one plant, we were able to get the same n+1 redundancy with fewer machines. We actually save some money that way. We have three large chilled water plants that cool a number of buildings in different areas of the campus, and that allows us to cut costs and have a dependable source of cooling. Otherwise you’d have to double up on everything. We’ve been able to do away with that.”

The University accomplished two major deferred maintenance projects valued at nearly $20 million (including operating shortfalls and construction financing) with virtually no overall long-term cost to its cash reserves, while providing a continuing positive cash flow to the operating budget through energy savings and savings on maintenance. When incentives from City of Toronto Better Buildings Partnership ($467,745.60) and Natural Resources Canada ($250,000), along with a $1.8 million interest free loan from the City of Toronto Better Buildings Partnership were factored in, the combined projects carried an overall payback of 14 years.

Energy Savings Measures and Results
The chiller retrofits, totalling $13.9 million in capital expenditures, was calculated to improve energy efficiency by 30 per cent. This translated into a drop in energy consumption of over three gigawatt hours (GW-h) annually, resulting in cost savings of $330,000 and a reduction in greenhouse gas emissions of approximately 800 tonnes of carbon dioxide (CO2) per year.

The lighting upgrade involved replacing approximately 86,000 lamps and 34,500 ballasts, at a cost of $4.4 million. Projected to reduce energy consumption by almost 9 GWh per year, the retrofit translated into cost savings of approximately $970,000 and a reduction in greenhouse gas emissions by 2,300 tonnes of CO2 annually. In addition, the University imposed a “Ban the Bulb” campaign, replacing all 7,500 remaining incandescent light bulbs and achieving an additional 201 kW demand reduction.

“It took us just over two years to finish,” says Dodds. “Everything was completed in 2008. We have seen savings, but at the same time, energy use is growing. Costs would have grown a lot higher if we’d not done this, so it has made an impact. Research programs are growing by leaps and bounds at the university.”

That isn’t the last of the energy saving projects the university has in mind. 

“We’re looking at a few other projects, smaller in scale,” notes Dodds. “We are doing a lot of infrastructure renewal projects, extending our district energy systems, adding chilled water capacity — we have to keep up with needs. A lot of the exterior lighting around campus is also being changed from high pressure sodium to either induction lighting or LED lighting. We are experimenting with LEDs in certain areas. We figure that they’ll pay for themselves just because they last longer.”

The university will also be working with the BBP on its infrastructure investments.

Project Snapshot
Annual reduction of 12 GWh in energy consumption
Energy cost savings of $1.3 million annually
Reduction in greenhouse gas emissions of over 3,100 tonnes of CO2 per year (equivalent to taking 600 automobiles off the road)
A reduction of 4.2 megawatts (MW) in peak electrical demand (10 to 15 per cent of the campus load)

For more information on taking advantage of the BBP’s programs, visit the organization’s website at www.toronto.ca/bbp/.