NRC Aluminum Technology Centre

Located in Chicoutimi in the Saguenay region of Quebec (the aluminum valley), the National Research Council of Canada’s Aluminum Technology Centre (NRC-ATC) was completed by the end of 2003. The centre, which groups all of NRC’s aluminum research activities under one roof, includes offices, a service section and specialized laboratories for the development and processing of manufactured aluminum components. Totalling 6,783 square metres on three levels, the $16.5-million centre was designed using an integrated design approach involving all the professionals on the team.

As mechanical and electrical engineers, Bouthillette Parizeau & Associates of Montreal proposed a combination of systems that is four times more energy-efficient than that of similar buildings, while keeping building operations simple.

Double-skin wall

Although they are increasingly common in Europe, double-skin walls are seldom used in Canada. Given its southwest sun exposure, this building has a double-skin wall in the atrium. The wall maximizes the benefits of solar heat during cold seasons and in winter cools the envelope by natural ventilation.

Air from the atrium is exhausted through the double-skin wall cavity after flowing through an efficient air-to-air heat exchanger. Outside air coming into the atrium is heated or cooled down, while the temperature between the two skins of the double wall remains temperate throughout the year, improving the building envelope thermal efficiency and users’ comfort.

Heating and cooling

The service core lies at the centre of the building, between the laboratories and offices, a location that reduces ductwork and piping distribution to a minimum.

Two heat reclaim chillers with a 300-ton total capacity provide chilled water for the building’s processes and air-conditioning systems in various parts of the building.

During the cold season, chilled water is partly produced by outside air preheating coils and by indirect-contact evaporative cooling towers. Heat rejected by the chillers is dissipated outdoors by the towers or used to heat the building envelope. Two natural gas boilers totalling 4,000 MBH are also used to complement the heating load. The tanks where heat transfer fluids are accumulated serve as a buffer for the cooling and heating networks.

Controls and office air-conditioning

A central control system for all the building mechanical systems also acts as a global energy management control system (EMCS). It manages and modulates the heating, ventilating and air conditioning system, using over 2,000 control points. The central control system, which can be operated over the internet, also governs the lighting, access and fire alarm systems in a bi-directional way.

The air-conditioning system for the office area is designed to optimize energy use for heating and cooling while ensuring high indoor air quality. It also serves as a back-up system for the laboratories area. A hot deck and a cold deck ensure efficient filtration, heating and cooling of supply air, as well as outside air for peripheral and interior zones. Variable frequency drives control the amount of supply air flowing through the decks according to demand. The cold deck can be arranged to operate as an air economizer to produce free cooling during mid-season. In each fan are bellmouths, an air flow measuring device, to ensure fan tracking.

The minimum outside air intake is ensured by a dedicated system that saves heating and cooling energy in several ways, all regulated by the global energy management control system.

* Preheating of incoming outside air is provided by a chilled water return, which generates up to 45 tons of cooling for interior areas and for aluminum processes.

* Outside air can be directed in whole or in part towards the cold deck to ensure free cooling, or towards the hot deck when the outside air temperature is higher than the return air temperature.

On the upper floors, air flow is controlled by single and dual duct terminal units. Air flow modulates to counter heat gains and losses, and heated air is only used to ensure a minimum of outside air in double-duct units. Return air is modulated to maintain a neutral pressure on each floor.

Laboratories area

The systems servicing this area are arranged in a flexible manner so as to offer several partitioning possibilities, as required by NRC. Air in the small laboratories is conditioned by local fan coils. Outside air flows in at a constant rate through a central system and is preheated by a chilled water return, as in the office area. A single system ensures general air exhaust. The amount of air intake and exhaust in each laboratory is controlled to maintain adequate pressure.

The larger laboratories (aluminum transformation and forming) are individually conditioned by dedicated units featuring an air economizer and natural gas duct heaters. For each laboratory redundancy is ensured using several units. Some fans are especially planned for exhausting air from aluminum processing, while emergency exhaust units are also provided in each laboratory.

Owner: National Research Council of Canada (NRC/CNRC) (Jean-Claude Gagn)

Mechanical-electrical consultant: Bouthillette Parizeau & associs (Jacques Legac, ing., Richard Labb, prof.tech., Pierre Roussel, ing., Andr Dore, ing., Andr Meunier, tech., Jean-Marc Deschnes, tech, Mario Toffolo, tech., Daniel Marchand, tech.)

Prime consultant/architect: Lapointe Voyer Lemay & associs

Structural consultant: LMB Saguenay-Lac-St-Jean

Construction: Pomerleau