Page 21 - Energize May 2021

NEWS

Study shows the power of passive

cooling technology

he South African
National Energy
TDevelopment
Institute (SANEDI) has
been rolling out “cool
surfaces” across the
country over recent
years, aiming to provide
a low-tech, but energy
efficient cooling solution
to communities. Many
partnerships and collaborations have enabled the coverage of hundreds of thousands of square
metres, coating roofs and walls with a heat-reflective substrate designed to lower indoor air
temperatures without the use of air conditioning.
“While provisional studies and data from other countries showed us that cool surfaces SABS_energize_03/2021
were a good investment, we felt it was important to formally document the results of non-
SANEDI initiated South African projects, to further demonstrate the impacts of local cool surface
interventions,” explains Denise Lundall, Project Officer, Energy Efficiency Cool Surfaces, at
SANEDI. Having worked extensively with the German Development Agency in South Africa, (the
South African - German Energy Partnership within the Deutsche Gesellschaft für International 75 Years of dedication
Zusammenarbeit (GIZ) GmbH) SANEDI made a request to them to procure the services of an to Quality Compliance
expert consultant to document the results of two projects undertaken by stakeholders in the hot
and humid Kwa Zulu-Natal province.
“Two sites were chosen – one industrial and one in the hospitality sector – to study the results SABS Appliances Laboratory is res-
of cool surface interventions in these applications. The assessment process included qualitative ponsible for testing of various house-
(survey-based) and quantitative (statistical) components. This enabled a holistic review and hold appliances within the test scope
analysis of the technology applied, its measurable and perceived effects, and acceptance among of VC 8055 Regulation.
researchers, manufacturers and prospective users,” Lundall says.
At the Saint Lucia Ecolodge along the Saint Lucia Estuary, isolated controlled experimental
metering proved to be successful in determining the effect of the technology. The study looked SABS Appliances is an accredited test
at the specific electricity requirements for one coated and one uncoated hotel bungalow. “Over facility to test geysers to the
the examined 24-hour period, a reduction of 1,3 kWh or 5% was observed. When you look at requirements of both VC8055 and
what this means over an average year in Saint Lucia, the lodge would gain a potential reduction VC9006. Compulsory Specification for
of cooling energy consumption in the order of 600 to 670 kWh, translating to a cost reduction of Hot Water Storage Tanks for
between R1200 and R1340,” explains Lundall. Domestic Use. These appliances have
The second study also took place in Kwa Zulu-Natal at Genkem, a manufacturer and
supplier of paints. They have developed a cool paint which was used in the pilot project, looking to comply with SANS/IEC 60335-1
at both the maximum temperature and the average temperatures over several days. “This and SANS IEC 60335-2-21.
helped establish the impact of cool coating technology in reducing indoor temperature, energy
consumption and demand. The study compared two repurposed containers: one coated and one The current setup has introduced full
uncoated,” says Lundall. It was found that the mean average daily temperatures differed by 1,9°C test automation of tests that are
and mean maximum temperatures differed by 7°C. performed on the test bench in both
Lundall says: “This is a substantial difference, and clearly demonstrates the significant potential
for reducing electricity demand for cooling and improving thermal comfort during hot South African SANS 60335-2-21 and SANS 151 test
summers. These results have further motivated SANEDI to continue promoting cool surfaces as an standards.
energy-efficient alternative to mechanical heating, ventilation, and air conditioning.”
SANEDI has also rolled out cool roofing projects in communities where local, unemployed SABS Lab improvements will reduce
people are trained as coating applicators to support the project, further adding to job creation. the test duration by about 50%.
“There is local capacity and capability in South Africa, which can be leveraged to support the
widespread application of cool coating in various sectors and building types,” concludes Lundall. Book your Lab
appointment
To see the full report please click here: https://www.sanedi.org.za/img/News/ZAF_20210222_
Final%20Report_Documentation%20of%20cool%20roofs%20experiments%20(1)_SANEDI_06042021.pdf NOW
0861 277 227
For more information, go to www.sanedi.org.za.
info@sabs.co.za
www.sabs.co.za

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