Urban homeowners can do their part to fight the effects of climate change by planting more trees – and even lower their own monthly electricity bill while helping to protect the environment from global warming.
Even just planting a small tree in your yard can make a difference on your monthly costs, and by letting the tree mature, you can save as much as $400 each year – according to a Cool Streets initiative, developed by architect Dr. Libby Gallagher. Gallagher’s PhD studied the impact of street design on temperatures and electricity costs.
“I found that you could basically achieve much higher levels of reduced energy consumption by planting effective trees on their street,” Gallagher said. “As the trees grow, the projected outcome for these streets was that when (the trees) were at maturity, they could achieve really significant benefits … providing shading, shaving electricity bills.”
Using data-modelling software, Gallagher’s study examined potential environmental outcomes generated by different layouts and tree species, focusing primarily on brush box trees, claret ash, deciduous, and gum trees. According to Gallagher’s results, trees should be more than seven metres tall to achieve the most benefit, but even a five-metre tall tree can provide savings of up to $100.
Dense tree coverage, she said, could lower temperatures in a well-shaded area by as much as seven degrees – which makes a big difference during heat waves like Sydney has experienced this summer, with a record number of days where temperatures exceeded 40 degrees.
According to Dr. Brent Jacobs, research director at the Institute of Sustainable Futures at UTS, trees work to reduce the “heat island effect” caused by the replacement of natural vegetation with infrastructure developments. These buildings absorb and retain heat during the day, contributing to rising temperatures in urban areas.
“Climate change only amplifies that urban heat island effect,” Jacobs said. “Whenever we change the landscape, we’ll get some urban heating going on, but it’s about how we plan those developments … and mitigating the heat before we start.”
The Cool Streets initiative has already been implemented in Blacktown, a western suburb of Sydney. For the trial, residential streets were retrofitted with more sustainable landscaping that uses trees and foliage to help combat the impact of global warming. The project was a collaboration between Cool Streets, Blacktown City Council, and the residents of the Glenwood community.
“Being able to empower these communities to have a discussion and a dialogue about the possibilities for their street allowed them to not only improve their environment, reduce their electricity bills, but also enabled them to feel like they could do something about this radically changing climate,” Gallagher said.
The smaller front and backyards included in most dense housing layouts, like in Blacktown, limits foliage options for most homeowners. The additional yard maintenance work associated with trees could also be a deterrent. Therefore, Gallagher said it’s critical that trees are planted along streets, requiring that city planners and developers step up and incorporate trees into their plans for future neighbourhoods.
This seems so obvious to me. Here in the Philippines, some streets of Manila benefit of trees, what a difference it makes! How comes that we don’t have more streets with large trees? Yes, there are roots that twist the pavement, if not managed well, leaves fall down and trees must be trimmed from time to time. Nevertheless, I bless these trees. Don’t wait for the borough to start planting them, take the initiative. The advantage of this study is to size the impact of planting trees in streets. There must still be enough light however. Same in the countryside. Trees, trees, trees. Each tree makes the earth less acidic and help reducing the temperature.