Telecommunications giant MTN reaffirmed its commitment to reducing its carbon footprint by unveiling Africa’s first concentrating solar cooling system, last month, which will power its energy-hungry data centres.

The system was designed by engineering consultancy AOS Consulting Engineers and renewable solutions provider Reach Renewable. It was implemented jointly by Germany-based thermal solutions provider Industrial Solar, South African renewable-energy solutions provider Voltas Technologies and air-conditioning contractor Luft Technik, which were supported by a professional team comprising turnkey solutions provider ISF Services, electrical consultancy and electronic engineering company Claassen Auret, industrial design and project management company ProjectWorks, global science-based company DSM and quantity surveyors Pentad.

The new system is driven by a cutting-edge technology known as linear Fresnel concentrating solar power (CSP), which uses heat generated from the sun and has a peak cooling capacity of 330 kW.

The system consists of 242 solar mirrors covering a total area of 484 m2, which tracks the sun to generate pressurised hot water at 180 ºC. The hot water, in turn, powers an absorption chiller that produces chilled water circulated into the data centre for cooling of information technology equipment.

The mirrors follow the movement of the sun, based on the global positioning satellite location, orientation and the date and time. This information guides the system to track the sun to concentrate on the central absorber tube where heat is generated.

The absorption chillers use a lithium bromide water solution, which uses water as the refrigerant. This is a completely green solution that has zero global warming potential and no ozone depletion potential. When it rains, the mirrors move into a self-cleaning position, and on cloudy days, the mirrors turn down into a protective stow position.

MTN South Africa CEO Zunaid Bulbulia says the CSP system cements MTN’s green credentials. MTN was awarded the first Silver Certified building in South Africa by the United States Green Building Council Leadership in Energy and Environmental Design certification programme in recognition of its sustainability efforts in all the operational efforts and commitment at the MTN head office building.

“MTN is acutely aware of the impact of global warming and its adverse impact on emerging markets including South Africa. We continuously explore ways in which we not only reduce our carbon footprint, but [in this case] it will substantially reduce our electricity consumption which will release additional capacity for the national grid,” he adds.

AOS Consulting Engineers MD Olu Soluade says: “The development of sustainable solutions and the implementation of technologies for the benefit of mankind is the prerogative of all of us. The continuous commitment to the reduction of our carbon footprint is the hallmark of sustainable development administered by professionals.”

“A sustainable way of life is essentially inevitable. It is our responsibility and our commitment to design and develop innovative solutions that foster a sustainable use of our resources,” adds Reach Renewable MD Frank Major.

Voltas Technologies MD Cristian Cernat explains: “The opportunity to model and design the installation using a high temperature heat source, architectonically integrated creates a real opportunity for local manufacturing and future jobs creation in the field of renewable-energy equipment production in our country.”

“Beside the solar cooling system, our state-of-the-art Concentrating Solar Linear Fresnel technology can be used for various applications in all kind of industries where process heat and cold or air-conditioning is required,” adds Industrial Solar MD Tobias Schwind.

German Energy Agency (dena) renewable energies project director Gabriele Eichner concludes: “This project is part of the worldwide dena Solar Roofs Programme coordinated by the German Energy Agency – and supported by the German Federal Ministry for Economic Affairs and Energy. We are happy that this innovative system generating green energy is now a part of the MTN strategy to reduce its carbon footprint. So this project is a win-win situation for all.”