While South Africa’s energy supply continues to fall short, government organisation the South African National Energy Development Institute (SANEDI) says it looks forward to continuing its roll-out of an energy efficient cooling solution – known as ‘cool roofs’.

Cool roofing involves the coating of roofs with a durable, reflective membrane which reflects the heat of the sun.

It is an inexpensive and highly effective passive energy, low-tech cooling intervention, notes the organisation.

SANEDI is one of ten global teams awarded a $100 000 grant by the Million Cool Roofs Challenge, to deploy solar reflective coating between August 2019 and December this year.

The Million Cool Roofs Challenge is a $2-million global competition to rapidly scale up the deployment of cool roofs in developing countries suffering heat stress and lacking widespread access to cooling services.

“The Covid-19 pandemic resulted in unfortunate and unavoidable delays in our implementation plans, but the challenge organisers have granted us an extension and a further $25 000 to get us back on track. Heading into what is sure to be a scorching summer, we are excited to resume projects across the country,” comments SANEDI energy efficiency project officer Denise Lundall.

Roll-out has started in the Makhado local municipality, in Limpopo, where 9 500 m² of roofing will be coated.

“Cool roofs offer a feasible and attainable solution that makes a tangible and, importantly, sustainable difference to South African lives, particularly those living in informal and rural communities,” explains Lundall.

Elsewhere in Limpopo, working in collaboration with the South African National Defence Force, 15 000 m² of roofing will be coated at a military site. On this same site, SANEDI is exploring the application of cool paving to complement the project and mitigate the “heat island” effect commonly experienced in urban areas.

“In Sharpeville, Gauteng, we will conclude the coating of three schools, where learners are sure to benefit from improved concentration and awareness levels, thanks to reduced indoor temperatures,” says Lundall.

Finally, in the Western Cape, SANEDI will be coating 26 000 m² of roofing on low-cost houses.

“Of these, the temporary housing settlement of Masonwabi will be both cool coated and insulated. This forms part of a proof-of-concept project to investigate the interaction and mutual benefits that cool roofs and insulation can achieve, when combined,” explains Lundall.

The project is being undertaken in partnership with the Thermal Insulation Products and Systems Association of South Africa.

The intention is to use the collected data as evidence for the mandatory inclusion of passive thermal control in the national Building Code, SANS 10400 XA.

“Cool roofing technology provides substantial energy savings, assisting in creating a greener economy that is more energy efficient and less reliant on mechanical cooling, powered by an already strained power grid.

"South Africa’s current energy supply woes are well known. However, as we proactively start moving over to renewable energy and energy efficient practices, cool roof technology will offer an attainable and low-cost, sustainable energy passive solution and forms an important part in this overall transition,” notes Lundall.