By: Mary Kate McGowan, Associate Editor, News
From ASHRAE Journal Newsletter, March 27, 2018
The air outside the Canadian High Arctic Research Station in Cambridge Bay, Nunavut, Canada, can be so cold that it must warm up about 108°F (60°C) before it becomes room temperature, according to Michael Brown, Student Member ASHRAE.
In winter the temperature in Cambridge Bay can drop down to –40°C (–40°F) or lower, without the wind chill, said Brown.
The Canadian High Arctic Research Station is planned to have reduced energy and water use despite the climate, long supply chains, periods of 24-hour light and darkness and expensive utility costs, according to “Resilient Design, Commissioning and Operation of the Canadian High Arctic Research Station,” a conference paper that was presented at the 2018 ASHRAE Winter Conference in Chicago.
Using techniques such as high-efficiency heat recovery to offset laboratory ventilation requirements and increased building envelope insulation, the research station uses resilient and sustainable practices to cut down on energy use amid polar temperatures. During the design process, simulation results estimated a 70% reduction in annual energy–use compared to a reference building, according to the paper.
“There’s definitely a desire to learn more about the Arctic...If we’re going to do it, we might as well do it in the most resilient fashion possible,” said Brown, who presented the paper. “There’s some conflict because on the one hand you want a facility that is easy to maintain in a remote location. But on the other hand, it has advanced laboratory facilities, so you can’t get away from needing things like fume hoods, which have substantial operations and maintenance requirements.
Resilience Strategies
Reduced energy consumption improves building resilience, according to the paper.
The paper defines resilience as, “the adaptability of buildings in response to adverse and emergency conditions.” The paper defines resilient design as, “the intentional planning of buildings, landscapes, communities and regions in response to potential vulnerabilities.”
All heating fuel, No. 2 diesel fuel, is delivered by truck and stored on–site. Because it is not uncommon for winter storms to delay the truck delivery, the station’s oil tank is sized to be able to “ride out” storms that last several days, according to the paper. An emergency generator provides backup power to critical systems, which include life–safety and scientific equipment for long–term experiments.
The facility is integrated into the local electrical grid, Brown said, and operates at a higher level of performance compared to a building designed to minimum building code and energy standards.
“Because of the very high heating load from building envelope heat loss and the heating of ventilation air, higher levels of insulation, high-performance windows and ventilation heat recovery were specified,” according to the paper. “These measures reduce heating loads compared to the reference building by approximately 80%. The use of LED lighting reduces expected lighting costs by 50%.”
Heat recovery for ventilation is critical, he said. The outside air being brought into the building can be –40°C (–40°F) or lower, and it must be heated up to room temperature, about 20° C (68°F), a change of 108°F (60°C), according to Brown.
“The addition of a heat recovery wheel made a huge difference,” he said.
The station’s two buildings each have a dedicated outdoor air system that allows fresh air ventilation to be separated from any remaining sensible heating load.
“Decoupling ventilation and space heating ensures sufficient fresh air reaches each space without over–ventilating and increased energy cost. In addition, hydronic loops are an attractive solution because they require less space than air ducting, and the associated pumps require less electricity per unit heat delivered than do the fans,” according to the paper.
The station’s adiabatic humidification system reduces the expected energy consumption compared to if the system used a more conventional steam system, Brown said.
“It’s a very dry environment. So for occupant comfort and to reduce static electricity detrimental to some scientific experiments, humidification is necessary,” he said.
In arctic regions, utilities are expensive. The conference paper reports energy and water costs are 5–10 and 20–30 times more expensive in Cambridge Bay than in southern Canada.
“Reducing process water, low-flow fixtures, that sort of thing made an improvement as well,” said Brown, adding that the station includes composting toilets and monitors water consumption.
Building in Permafrost
Another challenge of building in an arctic region is permafrost.
“The research station is located in a permafrost region, where average annual air temperatures are at or below the freezing point of water for at least two years,” according to the paper.
Building in a permafrost region requires different strategies than traditional foundations in a southern region, he said. If the ice in the soil degrades due to disruption from construction activities, it can negatively impact the building, he said.
“Once the permafrost degrades, it’s not coming back,” he said. “It can potentially disrupt the entire building. You’re going to get differential settlements and frost heaving.”
Luckily for the research station, the bedrock at the site is at a shallow depth, which allowed for the cost-effective use of bored and rock-socketed piles that effectively eliminated the permafrost thaw risk, according to the paper.
But that is not always an option and depends on how shallow the bedrock is and how deep the permafrost layer is, Brown said.
Renewable Energy Possibilities
Brown is studying how alternative energy resources can further the station’s resilience in the future.
More renewable energy resources could improve resilience by “diversifying the energy supply mix, reducing reliance on fossil fuels and protecting operating budgets from fuel price volatility,” according to the paper.
The only renewable energy at the station right now is a small building-integrated solar photovoltaic system meant for testing and demonstration purposes.
The research station has a comprehensive energy and water monitoring system that uses BACnet to support the station’s ongoing resilience. Once the system has collected enough data, it will be used to calibrate the building energy model to confirm the simulation model savings in practice, according to the paper. This will also help identify any needed corrective actions during building commissioning.
The detailed electrical data will also support the station’s testing of sustainable technologies adapted for the Arctic or for the planning of a potential renewable energy system.