The Northern Cape Province of South Africa is mainly semi-desert. In January, afternoon temperatures usually range from 34 to 40 degrees Celsius. In 1939, an all time high of 47.8 degrees Celsius was recorded at the Orange River.
Summer temperatures often top the 40 degree mark in this region (104 Fahrenheit).
This video explains how cool surfaces can help reduce indoor temperatures and improve the quality of life of those living in low-income housing in this scorching environment.
Reflective surfaces are cool in more ways than one, reducing energy consumption and saving lives one building at a time!
Scientists at the Lawrence Berkeley National Laboratory (LBNL) have created an interactive map that displays the solar reflectance (or albedo) of individual roofs in five major California cities – Bakersfield, Long Beach, Los Angeles, San Francisco, and San Jose. This is the first time scientists have attempted to map the reflectivity of entire cities.
A white / high-albedo cool roof reflects 80% of the sun’s heat, decreasing solar heating of the building. This reduces the need for air conditioning and lowers energy bills. Cool roofs could also partially counter increased urban temperatures brought on by climate change.
This map allows users to zoom in on a specific rooftop to see how it compares to the albedo of a white roof, or other roofs in the city, and is designed to help cities develop policies that could lead to cooler cities.
Ronnen Levinson, head of LBNL’s Heat Island Group and Board Member of the Global Cool Cities Alliance says this new map can be a useful tool for cities:
To assess these potential benefits for a particular city, we need to measure the reflectance of its roofs with good spatial and spectral resolution. Our map helps bring this into focus.
Our cities are heating up just as incomes are rising and the cost of air conditioning units are dropping around the world. This creates a vicious cycle that drives up energy demand, puts a strain on our infrastructure and pumps more carbon into our atmosphere. It’s little wonder that cities are looking for cleaner, cooler, and more sustainable ways to deal with urban heat.
That’s where the Clean Energy Ministerial’s Global Superior Energy Performance Partnership (GSEP) Cool Roofs and Pavements Working Group comes in. A new GSEP pilot program is being launched in Jasdan, India, where they will use cool surfaces and other energy efficient technology to reduce energy use and lower utility bills in low-income housing units. The project will also train local residents in the construction of “cool” homes. This initial pilot project will start with 8 homes, but it could help the Indian government adopt these cool surface technologies on a wider scale.
The Global Cool Cities Alliance (GCCA) is coordinating the Cool Roofs and Pavements Working Group. The goals of this working group are to reduce energy use in buildings, improve the health and resiliency of urban populations and help cities prepare for the warming effects of climate change. You can learn more about GCCA’s work on GSEP here.