Canadian Consulting Engineer

tuning up toronto

Thirty-four energy management companies recently got the good news that they are accepted into an innovative program being run by the city of Toronto. Firms ranging from the two-partner environmental ...

January 1, 2000   By Bronwen Ledger

Thirty-four energy management companies recently got the good news that they are accepted into an innovative program being run by the city of Toronto. Firms ranging from the two-partner environmental innovators Allen Kani, to the large multi-disciplinary consulting engineers H.H. Angus, to giant product manufacturers out of the United States, are on the list of firms now involved in the Better Buildings Partnership.

The Better Buildings Partnership was launched two years ago to encourage building owners to do energy retrofits. Run by the city’s Energy Efficiency Office, the program applies to buildings in both the public and private sectors. Its purpose is to arrange innovative financing such as interest-free loans, and act as the liaison point and clearing house between owners and energy management firms. Utilities like Enbridge Consumers Gas and Toronto Hydro also play an important role in the partnership.

Behind the program is an environmental imperative: to reduce carbon dioxide emissions believed to cause global warming. Richard Morris, manager of the Energy Efficiency Office, says that as a result of this initiative the city will easily do its part to help Canada achieve the reductions cited in the Kyoto Protocol. The city’s own more stringent official goal is a 20% reduction from 1990 levels by 2005. Already the program has reduced carbon dioxide emissions by 72,000 tonnes a year. The predicted savings from just one project under way, the Toronto-Dominion Centre, will be equivalent to saving the energy used by a small town — say, Bracebridge in Ontario that has 6,000 homes. The retrofit is believed to be the largest energy retrofit going on in North America.

Morris says that one important aspect that has emerged in their work is that “the debate between the environment and the economy is a non-issue.” Economics and environmentalism go together in the long term. Indeed, far from being a “money sink,” the Partnership has brought revenue in for the city by negotiating arrangements with the utilities.

By upgrading aging buildings, the program is also helping revitalize the city’s downtown core. Building owners lower their energy operating costs and improve their properties, so instead of retreating to new commercial properties on despoiled greenfield sites, hopefully more of them will stay downtown and continue contributing to the city’s tax base.

While the rest of Canada loves to hate Toronto, no-one can deny that the city has a stunning skyline worth preserving. The Partnership program has ensured that three treasured modern landmarks — now reaching that critical 30-year age — are being renewed rather than falling into neglect. Toronto City Hall, the dynamic 1967 creation of Finnish architect Viljo Revell, was one of the first to benefit from the program. First Canadian Place, a white tower on King Street West that is the tallest tower in the city, had an energy retrofit last year, and now an energy program is under way in the Toronto-Dominion Centre complex. Besides these high profile projects, smaller and older buildings like the 19th century Metropolitan United Church, and several apartment buildings have benefited from the program. As well, the Partnership has prompted a major energy overhaul of 126 schools around the city.

Toronto-Dominion Centre

When the first tower of the Toronto-Dominion Centre opened in 1967 it soared above the surrounding buildings in the downtown core and could be seen more than 30 miles away. Today the complex is flanked on all sides by other tall buildings, but is still distinguished by its simple, black steel, box forms. There are now five of these towers, including one that sits astride the old Toronto Stock Exchange

The first towers were designed by one of the most famous architects of the century, Mies van der Rohe (father of the phrase “God is in the details”). While the public tends to be ambivalent about the buildings’ stark aesthetic, most architects revere them as one of Canada’s most outstanding examples of modern design.

The original interiors are as elegant as their exteriors, so when the owners began the energy program, they decided to keep and refurbish the existing flush-mounted lighting fixtures, some of which date back to the 1960s. The mercury content in the lamps is being removed and over 99% of the materials are being recovered.

Ed Golfetto is the senior project manager for DukeSolutions the energy management firm in charge of the lighting and heating, ventilation and air-conditioning (HVAC) retrofit. The owner is Cadillac Fairview. Lead design engineers at DukeSolutions are Harold Murray, P.Eng. (lighting) and Kaya Corabatir, P.Eng. (HVAC).

The refurbishment of the lighting fixtures will improve the colour rendering index (CRI) from 53 to 85, closer to natural daylight. It also allows for the addition of a parabolic louver that meets IESNA RP-1 guidelines. The fixtures in the oldest three towers are being taken apart and stripped of their existing paint and refitted to hold a single high output long-life lamp and high output ballast. To do the work a dedicated assembly line has been set up by Metalumen manufacturing in Guelph.

Golfetto says that the logistics of the retrofit are formidable: “We enter the tenant space, floor by floor, night after night. We remove the old fixture and replace it with a refurbished one. We rezone the lighting circuitry while simultaneously installing a new building automation system network, wiring and panels for the control of the HVAC retrofit measures. This part of the work consists of changing the existing pneumatic perimeter induction unit to DDC and converting the internal constant volume system to Variable Air Volume (VAV). We hand the space over, fully operational, before the tenants arrive for work in the morning.”

The new T8 lamps and electronic ballasts (Osram Sylvania) together use less than half the energy of their predecessor T12 lamps and magnetic ballasts. In total 100,000 fixtures in the 4.5 million square foot complex will be retrofitted over 16 months. First to be done is the Ernst & Young tower on Bay Street, to be followed by the Royal Trust Tower in February. The total cost will be about $13.5 million, but it will be worth it. Predicted savings in power are 21,000,000 KwH, with consequent CO2 reductions around 35,000 tonnes.

A major effort is going into giving tenants control over light and air conditions in their own space. Where a uniform grid of lights now marches across the ceiling, it is being changed to a checkerboard pattern that can be adapted to the needs of different occupants. And unlike now where the air conditioning system supplies a constant quantity of cold air that has to be reheated to match the floor cooling load, the need for reheat energy will be eliminated with the new VAV system. To ensure adequate ventilation, CO2 sensors will ensure the quantity of outdoor air.

Heat to the buildings is supplied through the Toronto district heating system as steam. As part of the retrofit, the energy in the condensate, which was previously wasted, will be recovered and used to heat the parking garage ventilation air.

The existing Johnson Metasys building automation system (BAS) is being upgraded to handle the new, more responsive systems. A new fire-safety system will have a more user-friendly display and will be addressable with self-diagnostic devices that save maintenance. Together with an $8 million upgrade to high speed elevators, the total project cost is around $33 million.

Toronto City Hall

Another modern landmark in Toronto that has benefited from the Better Buildings Partnership is Toronto City Hall. Originating, like the Toronto-Dominion Centre, in the 1960s, its architecture is striking but greedy for air-conditioning energy. The city hall consists of two narrow office towers with full glazing on one side that soaks up the southern sun, curved around the “flying saucer” council chamber.

An earlier energy retrofit won an award from ASHRAE in 1987 and was the program which inspired the Better Buildings Partnership.The most recent program coincide
d with a major overhaul (by KPMG Architects) of the two lower floors of the building to accommodate the amalgamated Toronto city council. The council had voted to move in to the 1960s building rather than much newer facilities to the west in Metro Hall.

DukeSolutions was the energy management firm for City Hall. Paul O’Sullivan, P.Eng., a consulting engineer with the company who oversaw the work, describes the measures taken:

“The existing lighting fixtures in the basement ground and second floor were T12 fluorescents and drew 192 watts per fixture. Of these 3,000 were converted to T8 lamps drawing 60 watts yet providing an equivalent illumination.

“In the council chamber we replaced the perimeter incandescent lighting with indirect strip fluorescents, and the existing ceiling-mounted incandescent lamps with longer lasting quartz lamps.

“In total the lighting load was reduced by 32 kilowatts. This in turn resulted in a refrigeration load reduction of 120 tons of cooling. The plant capacity was reduced by 22%. A 900 ton chiller that operated on ozone-depleting freon 11 and was 33 years old was replaced with a smaller 500 ton chiller operating on an environmentally benign refrigerant. It is 15% more energy efficient. Variable speed drive controls were installed on cooling system pumps, reducing pumping energy by 50%.”

The energy retrofit has cut consumption from 36.8 KwH per square foot per year to 29.2 KwH. However, the benefits have spread far beyond the city hall. The city was able to use the cost savings in that building to replace 20 aging boilers in other facilities without having to have approval for capital spending. In total seven buildings (788,779 s.f/73,277 m2) benefited. The St. Lawrence Market and Allen Gardens conservatory, for example, received new natural gas and electric heating systems. The total energy savings from all these projects are 6.6 million KwH. The capital cost was $4 million, and the savings are around $570,000 per year, giving a seven year payback. Carbon dioxide emissions have been reduced by about 6,600 tonnes a year.

Metropolitan United Church

A smaller project in the Better Buildings Partnership program is the Metropolitan United Church located on Queen Street East, downtown. The church dates back to 1872, with a three-storey 1930 addition called the Church House. The latter is partly used as a refugee shelter, drop-in centre and overnight hostel for the homeless.

The two buildings had many lighting and HVAC problems. In the gymnasium used as an overnight hostel, for example, the ventilation system was not introducing any outdoor air. A vacuum condensate return system also was not working, resulting in high heat and humidity that was warping doors and creating bad window condensation and damage.

In the sanctuary temperature fluctuations and dry air were causing problems, particularly for the wood pipe organ. The nave’s 70-foot high ceiling creates a strong stack effect, and air was escaping through a barely insulated roof. Light levels were low, and the self-ballasted mercury vapour lamps cast a greenish tint over everything.

One of the main changes of the new energy retrofit was the church’s decision to connect to the Toronto district heating system. Pre-insulated pipe was tunneled from a hospital across the street into the old boiler room in the church. City steam pumps in at a pressure of 125 lbs. and is reduced to 5.5 lbs.

Rose Technology Group (Peter Daldoss, P.Eng.) was in charge of the energy retrofit for Better Buildings Partnership, with Building Innovation (David Dengler, P.Eng.) helping in the work. Among the remedies they specified is a new building automation system and a new steam condensate heat recovery system.

In the sanctuary the building automation system works to modify the varying conditions that occur in different parts of the large space. It interacts with five control points and five zone temperature sensors to control 15 valves on the radiators as well as the ceiling fans. A heat recovery coil valve and an air handling unit both modulate to ensure maximum heat is recovered. Outdoor air is used for cooling.

Throughout the complex light levels were increased from 10% to 50%, and in the sanctuary by 100%. For example, lighting behind stained glass windows was retrofitted using metal halide flood fixtures with 3700K 80 CR 400 watt lamps and reflectors. Their ballasts were mounted remotely so that they would not be subjected to high temperatures in the attic during the summer..

Outdoors, where the owners wanted more light for security, the energy firms specified high pressure sodium lamps on posts and floodlights. They increased light levels 100%.

Overall the operating cost savings are expected to be around $20,000 annually, with a 10-year payback on energy saving equipment. Energy use is reduced by approximately 860,400 ekWh, reducing CO2 emissions by 242 tonnes a year.

Dengler says that the project was a rewarding one because the client was willing to take a long term view and commit to a complete building overhaul. There were, for example, lots of improvements to the building envelope, including the addition of 8 inches of blown cellulose insulation in the sanctuary attic and the installation of storm windows to protect the leaded and stained glass windows.

The project won an ASHRAE Technical Award for eastern Canada last year.CCE


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