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Quebec researchers look to use groundwater to cool buildings, reduce dependence on A/C

During heat waves, air conditioners provide relief from high temperatures, but they also pump hot air outside and consume massive amounts of energy.

Quebec City has ‘great potential’ for groundwater cooling systems

About 10 per cent of global electricity is consumed by fans and air conditioners, according to the International Energy Agency. (AP Photo/Nevada Appeal, Brad Horn)

A team of Quebec researchers is trying to find a new way of beating the heat by using groundwater to cool down buildings and reduce the climate impact of air conditioning units.

During heat waves, air conditioners provide relief from high temperatures, but they also pump hot air outside and consume massive amounts of energy.

About 10 per cent of global electricity is consumed by fans and air conditioners, according to the International Energy Agency.

Jasmin Raymond, a professor at the Institut national de la recherche scientifique (INRS), believes groundwater cooling systems could reduce energy consumption by about 90 per cent.

"The idea is to develop those methods to actually reduce the power demand that is associated with cooling during a heat wave," Raymond said.

The Canada-wide project, dubbed Aquifroid, is being run by the National Institute of Scientific Research.

It has identified Canadian cities with high potential for such a system, including Quebec City, Vancouver, Toronto, Moncton and Kitchener.

Those cities have shallow aquifers, which are water-bearing permeable rock that can be tapped with a well.

Raymond said the Limoilou and St. Roch neighbourhoods of Quebec City are ideal because of their shallow aquifers and their existing susceptibility to heat waves.  

Not only do A/C units push hot air outside, they also consume energy, whereas groundwater temperature is relatively constant, and stays at about 7–8 C underneath Quebec City.

The INRS wants to find a way of pumping heat from buildings into groundwater, while pumping cool groundwater through the building to bring the inside temperature down.

Raymond said the setup is almost identical to a groundwater heating system, which already exists in several places.

He said the new model would provide additional energy savings because it wouldn't need any electricity, just a circulation pump to move the existing cool water throughout the building.

"With our project we will be looking at both what are the opportunities for space cooling using groundwater — because obviously there could be many advantages — and what are the risks," he said.

"We can try to develop this practice and also improve regulation with respect to groundwater to promote this use, but at the same time make sure we have no impact on groundwater resources."  

Groundwater is also used for drinking some locations, so Raymond said it's important to understand the consequences of a groundwater cooling system on drinking water to make sure there are no chemical reactions caused by pumping hot air underground.

Researchers hope to pilot the system on a small scale starting next year.

Based on an interview with Quebec AM