‘With glowing hearts,’ as our national anthem goes, the proud citizens of British Columbia (and Canada) will welcome millions of international visitors and billions of television viewers to Vancouver and Whistler during February. Our hearts will be glowing and so will gas boilers throughout the beautiful new sports facilities where 5,000 of the world’s best athletes will compete. In many cases, however, less energy will be burned than at past Olympic Games, as the greening of the world’s mechanical systems continues. In venues with ice sheets such as the Richmond Olympic Oval for speed skating, Vancouver Olympic Centre for curling or the University of British Columbia (UBC) Arena for hockey, heat energy exhausted by the ice making equipment will be recovered and used for space heating and domestic hot water. Some of the buildings with large roof areas are using them to collect rainwater, which supplies waterfalls, ponds, toilets and irrigation systems. These processes are increasingly common, but a few other Olympic mechanical systems are almost radical. In both Whistler and Vancouver a new approach is being taken to district heating and cooling that combines principles from bioengineering, heat recovery and geothermal systems. And the Richmond Oval, destined to become the TV star of the Games, boasts an HVAC system that is completely unique and truly state-of-the-art.
Maintaining a precise temperature and humidity level in the Richmond Speed Skating Oval while keeping spectators warm proved a challenge.
The Oval uses stunningly beautiful pine (from B.C. forests ravaged by mountain pine beetles) across the entire ceiling expanse of its massive 46,600 square-metre structure. Designers concluded they couldn’t spoil the look by adding exposed ductwork. Instead they lined the V-shaped 100 metre arches with tin, drilled through and installed nozzles. The arches became the ductwork and housing for sprinklers and other systems. Olympic rules require 40 percent relative humidity levels, a minimum ice quality and a temperature above the speed skating surface of 17oC, which is a little cool for 8,000 spectators at each event. Therefore, specific ducts and three 53,000 cfm air handlers, that can be utilized or shut off to adjust to load requirements, provide heating in the main Oval Hall. A control system by ESC Automation manages this according to occupancy conditions, thermal control zones and perimeter exposure. To save energy, variable speed drive pumps are used in the heating loop, cooling loop and cooling tower, and heat is recovered from both the refrigeration plant and from desiccant dehumidifier regenerated exhaust air. Refrigeration plant heat recovery also makes up 21 percent of the DHW energy requirement. In addition, a 100-metre earth tube is buried on the northeast side which provides ground source pre-conditioning of incoming air to a fourth, perimeter zone air handler.
Whistler had closed a landfill operation that resulted in a big brown field between the town and the riverfront; and has long needed more affordable housing for resort employees. When it was announced that 2,200 VIPs were coming to town for a six-week stay-over; the town saw the three challenges as one. It now had a strong mandate to clean up the landfill, build affordable housing, and upgrade its infrastructure. It pre-sold the housing to residents at below market rates with move-in dates after Olympic visitors leave in March. It then built an environment-friendly sewage treatment plant and district heating/cooling system. The plant uses microbes that chew up harmful nutrients in the sewage, reducing nitrogen and ammonia toxicity and minimizing impacts to the Cheakamus River. Ultra violet disinfection provides protection against waterborne diseases. A huge volume of hot water energy goes down the drain from showering, bathing and cooking. This combined with the anaerobic treatment (oxygen bubbles blown into wastewater for the microbes) results in sewer water temperatures averaging 9.5oC. The new District Energy System extracts low-temperature ambient heat from the sewage via two cleanable plate-type heat exchangers. Each is capable of handling the full load while the other is being cleaned. A high efficiency natural gas boiler in the plant boosts the temperature to about 12oC and variable frequency pumps move the pre-heated water into the closed loop two pipe reverse return system serving the housing and training centre in the Whistler Athletes Village.
Part of the solution involved using the pine ceiling beams as HVAC ducts. (City of Richmond photos)
Designers had to come up with a way to prevent humidity at the adjacent pool from affecting the curling rink. (City of Vancouver photo)
Eighty percent of the heat energy required to heat village housing comes from the system. Electric boilers provide additional capacity on the coldest days, along with DHW. To help combat seasonal and day/night above-ground temperature variations, the system uses oversized high density polyethylene pipe, buried about six feet below grade. The geothermal effect on larger volumes of water helps maintain and moderate temperature variations while the sheer size of the distribution network creates thermal storage, reducing peak system loads. The system is designed to produce up to 11,000 mWh of building heat energy per year and will reduce greenhouse gas emissions by 96 percent compared with conventional heating technologies.
The district energy system picks up heat from wastewater.
Swimming versus curling
In the Vancouver Olympic Centre, the curling facility and pool facility are interconnected and constructed as one building. However, the moisture from the pool cannot be allowed into the cooler curling arena where it would condense on the ice surface and affect quality. IOC guidelines specify humidity, temperature and air velocity. A computational fluid dynamics model was created to fine tune the HVAC system and differential pressure is maintained between the two spaces to prevent migration of moisture. Within the curling arena, air is discharged through perforated ducts below the bleachers at low velocity, and returned via grills behind the bleachers. This supplies an even distribution of air for the spectators. Air flow and direction over the ice surface is provided via motorized variable flow diffusers. This facility will recover heat energy from the ice plant and use it for space heating, pool heating and domestic water heating. HRVs are also used to pre-heat incoming fresh air. The building is expected to consume energy about 40 percent below the model national energy code building (MNECB). Low-flow plumbing fixtures and rainwater will support a goal of 60 percent water savings.
Workers lay pipe for the district heating system at the Athlete's Village.
While the athletes pursue gold and silver medals, the Olympic sports venues with their unique energy saving technologies will seek gold and silver LEED ratings. Achievement levels are still unknown but one thing is definite: Canadians will be radiant with glowing Olympic torches and glowing hearts.
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