When the city simmers during summer, enterprising households have been painting their rooftops with a white paint to reduce the searing temperatures by a few degrees to get some relief.
With sweltering summer days reaching close to 50 degree Celsius that has become a norm of late, there is hardly any way out for citizens, especially the poor and the downtrodden who rarely have the wherewithal to have even air coolers or to pay high power bills later.
The Administrative Staff College of India (ASCI), University of New South Wales (Sydney) and DuPont have joined hands to conduct an interesting experiment to combat the heat wave, albeit on a small scale in the twin cities.
A rooftop removable all-weather barrier polymer ‘Tyvek’ made by the multi-national giant is being tested as a method to protect low-income households from the summer heat. It involves installing a sturdy polymer sheet on nearly 1,000 square metres of households and setting up sensors to monitor the indoor environment.
“Women, children and even the elderly living in the slums bear the summer brunt. The white paint is effective, however, it is expensive and has to be repainted every year. With this new material, we want to see if it can provide cost-effective relief,” explains Rajkiran Bilolikar, associate professor, Centre for Energy, Environment, Urban Governance and Infrastructure Development, ASCI.
Multiple use
The foldable thin sheet can be easily removed when not required. The material can not only hold up to showers, but also be a pretty decent mattress. In fact, his team in collaboration with a U.S.-based NGO Natural Resources Defence Council and IIIT-H’s Vishal Garg had already tested Tyvek for about a fortnight in May on about 30 dwellings at Devarkonda slum in Banjara Hills. “There was a 2 to 3 degree difference in the temperature. It took a while to convince the householders, but now more are ready to join us,” he claimed. Now, with the help of UNSW, and DuPont providing free sheets, it is being tested on small number of dwellings in the same slum, this time for eight months till the summer-end.
With the help of sensors, researchers would measure indoor temperatures, humidity and air quality besides thermal comfort inside homes and energy consumption to test the effectiveness of the cool roof material in reducing indoor heat and thermal exposure.
“The project aims to enhance opportunities for research, knowledge exchange and technology transfer in the areas of energy poverty and urban sustainability. It also has the potential to scale for an entire community,” says Komali Yenneti of UNSW.
