Extension Calgary International Airport, Calgary, AB, Canada | Architect: DIALOG Design | Photo: Peter Sellar
Warm summers and cold winters characterize the climate in the prairie near the Rocky Mountains. Additionally, the autumn wind „Chinook“ can increase winter air temperatures from -20°C to +10°C (-4°F to 50°F) or more within hours, which then fall back to baseline. The wind speed can be over 120km/h. The new construction of the international airport in Calgary doubles the capacity of the existing one.
In a holistic approach, the design team has developed an integrated climate and energy concept for the building. The approach stipulated that one should be able to see as much of the city skyline and the mountains as possible, but at the same time controls the amount of heat and solar radiation that reaches the interior. While adequate natural daylight should be available, no one should be blinded by sunlight. On façades subject to elevated levels of sun exposure, a double-skinned glass façade with efficient sun protection in the façade gap is used to optimize solar inputs and daylight. The double facades form a thermal buffer zone, which is naturally ventilated by chimney effect. Ventilation flaps are closed at night and in winter to prevent heat loss. The reflective blinds between the inside and outside glazing are weatherproof but perforated to 10%; which means that the incoming sun is efficiently shadowed, visual contact to the outside is always maintained, yet one is not blinded by the light. An automatic control combines excellent daylight conditions with good sun protection; skylights also provide additional daylight, while a micro-sun protection grid integrated in the glazing prevents glare from direct sunlight. Daylight-controlled LEDs provide electrical lighting.
Underfloor heating and cooling works with connection to a geothermal system. With 580 geothermal boreholes at 500ft. (approx. 150m) depth distributed across four areas, it is the largest geothermal field in Western Canada. The system provides basic heating in winter and the efficient dissipation of heat loads into the ground. Due to the radiant cooling systems, air conditioning via conventional air circulating is mostly not required. Fresh air enters the space near the floor at a low velocity and, instead of mixing with stale air, slowly displaces it upward and away from occupants. This system works with thermal stratification, is draft-free, quiet and guarantees excellent air quality and comfortable room temperatures. It can also respond quickly to fluctuations in the outside temperature/solar radiation. In addition to geothermal energy, combined heat and power systems are available for self-generation of electricity and heat. The roofs of the buildings are prepared for future installation of photovoltaic modules, which could further improve the overall energy balance of the new terminal. The project targets LEED Gold.
Within the scope of the project, active systems and control strategies were mapped by means of TRNSYS simulation. It was tested which optimization potentials exist with alternative approaches. The geothermal field and the corresponding plant components for the generation of heat and cold were used and showed that with an appropriate control strategy the heat balance in the ground can be optimized.