What Happened?
Sydney is replacing traditional dark or black street surfacing with a paler coating to reduce radiant heat that contributes to the urban heat island effect. The pale recoating roads project is part of a larger initiative to reduce carbon emissions and global warming in Sydney.
The Goal
Conventional black or dark street surfacing is prone to absorbing heat from the sun during the day and discharging it into the atmosphere at night, which in turn increases inner city temperatures. As roads heat up in the summer time, urban settings can become hot boxes, which forces residents and businesses to turn up their air conditioning and use more energy to cool down. When these electric devices are turned on, more warm air is emitting back into the community, further exacerbating the problem. This is known as the urban heat island effect.
Sydney officials want to recoat the roads to help support broader efforts to reduce carbon emissions as well as improve the quality of life for inner city residents. The city will use open grade asphalt pavement filled with concrete slurry, which will create a lighter-colored surface.
Experts suggest concrete and cement stores more heat than natural materials, which contribute to higher urban temperatures. This is a problem for both roadways and building rooftops, which heat up buildings when they are coated in dark or black surfacing. City temperatures can increase by up to eight degrees when roads and roofs are covered in dark surfacing, and there is limited shade from trees.
City officials will then record temperatures across the city to see if ambient temperatures drop in regions where the streets have been recoated. Sydney is implementing a number of strategies to counter rising temperatures and reduce carbon emissions in response to reports predicting population growth and climate change will increase the city’s temperature in the next few decades.
Modernizing Roofs, Roads
Aside from coating roads with lighter, more natural materials, many cities are taking their highway modernization projects one step further with solar technology. Experimentation with solar panel roads are underway which convert solar energy into electricity without increasing urban temperatures but potentially cutting greenhouse gases by 75 percent.
The solar panel roadways are equipped with microprocessing solar units locked together, which are then covered with tempered glass material to withstand impact from vehicles and weather. The panels collect solar power, heat themselves in cold weather and generate electricity to provide light on the road at night. The electricity can also be channeled back into the community to reduce energy costs for homeowners and businesses.
There is also a strong push all over the world for more installations of cool roofs in dense urban environments to lower temperatures and carbon emissions. These roofs reflect sunlight and heat away from a building, allowing it to remain cooler without increased electrical use. Cool roofs have proven to reduce building heat by up to 60 degrees in cities during warm weather months.
Soaking Up The Solar
Gov1 has stayed abreast of the latest solar power trends, including adding panels to clocks, rooftops and other green infrastructure.