Centre Communautaire de Mistissini

Mistissini is a Cree village on the southwest shore of Lake Mistassini, the largest natural lake in Quebec, located 100 kilometres northwest of the city of Chibougamau. The town has a population of about 3,500 people.

Its new community centre, the Centre Communautaire de Mistissini, houses an arena with locker rooms for players and referees, a gymnasium, fitness room, library, fast food service and offices. The 6,415-m2 centre is funded by the Grand Council of the Crees and managed by the region’s Cree community.

Dessau carried out the engineering design (mechanical, electrical, structural and civil engineering) for the building. It complies with sustainable development principles and has high energy efficiency.

Most arenas in Quebec use chillers with standard condensers to produce and maintain the ice. The extracted heat is then rejected outside through air condensers. In Mistissini’s arena, low-temperature heat pumps reject the refrigeration heat into two methanol/ water loops. These loops then supply the radiant floor heating for the grandstand, and the heating for the community centre’s premises, via heat pumps. The loops also supply preheating of domestic hot water, and heating under the rink slab to prevent the soil from freezing. Most of the arena’s heating load is therefore met by rejected heat from the mechanical cooling used to maintain the ice temperature. These water loops are also connected to a geothermal loop comprising 28 vertical boreholes 152 metres deep that provides the remaining heating load. Moreover, by adding enthalpy wheels to the ventilation units, the energy usually lost in exhaust air is efficiently recovered and used to preheat incoming fresh air.

Furthermore, the arena includes a cold storage mass made up of approximately 0.5 metres of compacted sand under the slab of the rink. This cold storage mass contains a system of pipes where secondary refrigerant is circulated at night. During the day, this stored “cold” helps reduce the load on the heat pumps and reduces the electrical peak demand.

The use of geothermal energy as well as heat from the ice-making process and from exhaust air, together significantly reduce the heating and cooling needs of the centre. Thanks to these innovative systems, the community centre consumes 62% less than a similar building respecting the Model National Energy Code of Canada for Buildings. The savings are 1,595,231 kWh per year, or $153,600.

Greenhouse gas emissions are reduced by 350 tons per year.

Energy simulations benefits

Climatic conditions in northern Quebec present a significant challenge when designing high energy performance buildings. Moreover, arenas are particularly complicated since their high cooling and heating needs must be addressed simultaneously.

The yearly average load of a building, whether in heating or cooling mode, is generally below 50% of the maximum load; therefore selecting equipment that can offer good efficiency even at partial load is important. This is where energy simulations become essential in order to properly assess the needs and behaviour of a building’s various systems. With the use of DOE2.1e software, simulations were conducted to evaluate the optimal load of the heat pumps as well as the geothermal network.

The total construction cost for the project was around $18 million, of which $1 million was dedicated for energy efficient systems. With incentives of $290,680 from energy suppliers, the payback period for the energy efficient systems is 4.6 years.

Dessau was involved not only at the design stage, but also for geothermal studies, technical support and construction supervision. After construction, Dessau remained present during the equipment control and adjustment phase to ensure that needs were met.

Completed as planned in August 2007, the centre has many positive benefits for the community. A second work phase is in the early stages for the addition of a public swimming pool.

Name of project: Centre communautaire de Mistissini, Quebec

Award-winning firm (mechanical, electrical, structural and civil engineering): DESSAU, Montreal (Frdric Sauriol, ing., Alessandro Cirella, ing., Laurier Nichols, ing., Jacques Bouchard, ing., Ann Marie Connely, ing., Edith Sweeney, ing., Alain Higgins, ing., Stphane Sirard, ing. Charles Mercier, ing., Charles Julien, ing.

Owner/client: Council of the Cree Nation of Mistissini

Architects: Guilmette Larue + Leziy + Bart, Fortier, Gauthier in consortium