MTN announced in a press release on Wednesday, 9 July 2014, that it has built a concentrating solar cooling system to provide power to its data centres, claiming it as a first for Africa.
The system was designed by Reach Renewable and AOS Consulting Engineers, and implemented jointly with Industrial Solar, Voltas Technologies, and Luft Technik.
It is supported by ISF Services, Classen Auret, Project Works, DSM, and Pentad.
According to MTN, the system is driven by technology called Linear Fresnel Concentrating Solar Power (CSP) that uses heat generated from the sun and has a peak cooling capacity of 330kW.
The system consists of 242 solar mirrors covering a total area of 484 square metres, which can generate pressurised hot water at 180 degrees Celsius.
This hot water powers an absorption chiller that produces chilled water, which is circulated into the data centre for cooling IT equipment.
MTN said the mirrors follow the movement of the sun based on their GPS 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, MTN said.
When it rains, the mirrors move into a self-cleaning position, while on cloudy days the mirrors turn down into a protective stow position.
The absorption chillers themselves use a lithium bromide water solution, which uses water as the refrigerant.
“This is a completely green solution that has zero global warming potential (GWP=0) and no ozone depletion potential (ODP=0),” MTN said.