Pools are huge energy guzzlers. Heating and keeping warm is a costly affair, especially for cities that operate large public pools. But these pools are also required by communities. So when cities try to placate their citizens, they often make a compromise — by providing a popular public utility and paying for the energy it consumes.
A new community center design suggests compromise may no longer be necessary. The North East Scarborough Community and Childcare Centre, currently under construction in Toronto, will be Ontario’s first net-zero energy community recreation facility with swimming pools when it opens in 2024. On the lower level, a six lane lap pool and adjacent leisure pool has been designed to operate as efficiently as possible, with all energy consumption provided by on-site heat and power generation.
There are more than 300,000 public swimming pools and more than 10 million private swimming pools in the United States, and an estimated 96,000 additional private swimming pools were built in 2020 alone. All of this adds up to significant energy consumption. One study suggests US pools use between 9 and 14 billion kilowatt hours (kWh) of electricity Electricity needs of 11 states. A study of public pools in San Antonio, Texas found that the average annual energy cost of a traditional pool heater was more than $12,000. In colder Toronto, those numbers would probably be even higher.
Places like Toronto are rethinking how these giant energy consumers are powered. The new community center offers what the city is hoping for as a model. The four-story community center features a gym, running track, child care facility and indoor cricket pitch surrounded by a public park. As an all-electric building with significant on-site renewable energy production, it is expected to produce as much energy as it uses – and produce net-zero emissions.
Designed by architectural firm Perkins&Will, the project is a pilot project for the city of Toronto, which hopes to make all of its community centers and other urban projects equally energy efficient. Addressing the problem of pool energy was a primary goal. “This was a pilot project for both the city and us,” says Zeina Elali, Senior Sustainability Advisor at Perkins&Will. “It’s a challenge in the industry.”
Pools pose a major energy challenge for architects like Elali, whose job is to help clients get the projects they want while reducing their environmental impact. This requires more than just replacing LED lights or adding some photovoltaic (PV) panels. “I think many in the private and public sectors have already reached for the low-hanging fruit,” says Elali. “It was time to tackle the bigger carbon emitters.”
The pools in the new community center will have a reduced energy load due to some unique design solutions. One is that they are both semi-buried underground, which thermally insulates them from Toronto’s often freezing winter temperatures and reduces the amount of artificial heat they require. The pools also use electric air source heat pumps that transfer heat to or from the outside air to quickly generate heat for the pool. With the same amount of energy, these highly efficient heat pumps can produce three times as much heat as a conventional heating system based on fossil fuels.
Even with this more efficient heating, the pools still require energy. “You’re never going to get consumption to zero, so get it down as much as possible through mechanical efficiency,” says Christina Grimes, associate at Perkins & Will.
The rest of the energy needs are met by the project’s expansive and inventive PV panel arrays. The roof of the building is covered with solar panels, as is a large parking lot, which will also serve as a space for a weekly farmers’ market. A walkway connecting a nearby housing development has a narrow overhead PV canopy, and the building itself has PV panels integrated into the facade. “We have every type of PV system you can think of for this project,” says Grimes.
To help the project meet its net-zero emissions goal, the designers worked from every corner and focused on reducing the building’s operational and construction-related emissions, known as embodied carbon. Choosing a lower-emission concrete mix reduced overall emissions by 24%.
These energy efficiency efforts don’t come cheap, but the architects argue that the upfront investment costs are more than offset over time. “Your electric bill should be zero,” says Grimes. “A 30-year time frame is how you have to think about the return on your investment.”
More and more communities are seeing the wisdom in making these investments. Perkins&Will has designed two more net-zero community centers for other Ontario cities, and construction on both is scheduled to begin later this year. Everyone will have a pool.