AFRICA’S increasing urbanisation affords contractors a “clean slate” to build cities differently from the ground up, and firms are increasingly taking the green route.
A good 60% of firms surveyed in South Africa for the World Green Building Trends report 2013 say they have plans to construct new commercial buildings with green features, and 58% report plans to retrofit existing buildings with environmentally sound technology.
Notably, respondents in the country indicated that over a third (36%) of firms report planned green activities for low rise residential projects as well (one to three floors), one of the highest planned rates for residential projects among the nine countries surveyed globally.
It suggests that the increasing popularity of green technology is dove-tailing with baseline demand for housing in general, presenting a golden opportunity to create a different kind of urban environment.
One notable example of an early starter is the Mauritius Commericial Bank with its headquarters in Ebene, 15 kilometres south of the capital Port Louis.
In an area that is witnessing an explosion of steel and glass structures to house the island’s kings of finance and commerce, the building stands out among its peers. While it outscores the competition on its outside looks, it is on the inside that it is really unsurpassed in terms of eye-catching design and environmental consideration.
The building is the first in sub-Saharan Africa to achieve the prestigious BREEAM (Building Research Establishment Environmental Assessment Methodology certification).
The carefully chosen building orientation ensures that the façades face due north and south to maximise on the sun’s energy as it shifts position throughout the day, with generous overhangs which virtually eliminate all direct solar gains or what is commonly known as the greenhouse effect.
Next to the building is a photovoltaic farm consisting of 2162 solar panels that is used to generate 60% of the consumption of the building.
The farm produces 2500Kilowatt hours during sunny hours and 1000 Kwh on cloudy days and is oriented due north owing to the fact that Mauritius is in the southern Hemisphere. Inside the building low-energy consuming lamps are used. The genius is that the building uses sensors to know when to turn the lights on and off, or draw the blinds on the windows.
Natural air is used as much as possible for cooling through a floor displacement ventilation system where it is funnelled in at the ground level and extracted at a level above, and rainwater is harvested for various uses including irrigation of the surrounding grass (the building sits on six acres), flushing toilets and cleaning.
There is also a composter/digester for waste that is used to make soil compost for the garden. More work is ongoing with the integrated building energy management team from Siemens to improve the system, for example by making better use of solar light.
If business surveys are to be believed, soon it will not be alone.