Sustainable design has become integral in the design and construction of buildings in many parts of the world. In South Africa the trend is growing quickly where architects and engineers are coming up with alternatives to offset the pressure on energy generation which is becoming a serious concern. Whilst in Africa the uptake is slower due to infrastructure and regulation limitations, it is still a critical concern and companies are becoming more aware of this phenomenon to improve efficiencies and allow for long-term return on investment.
In fact, implementing green building practices aligns ones company in terms of the bigger picture of climate change mitigation. In Africa, industry is embracing this necessary shift towards sustainable practices as it has a proven and significant economic business case.
That said, heating, ventilation, and air conditioning (HVAC), lighting, and even the type of paint used are all components of sustainable design – and are becoming increasing important to consider. But equally important is being cognisant of the building site and the need to minimise the impact on the ecosystem considering waste reduction and recycling, and using more sustainable materials in construction.
Certain passive design elements (i.e. the form and fabric of the building envelope) that influences the intrinsic makeup of a building, prior to things such as air conditioning and lighting is one of the most effective means to achieving significant ongoing sustainability.
An example of this is the use of solar panels on a green roof. The panels provide shading to the roof that prevents the solar gains from even reaching the occupied space. In other words, you do not have to expend energy extracting hot air with an air conditioning system. The green roof also adds a layer of thermal insulation that further prevents heat gains from entering the space, which can result in up to 10% energy savings. The green roof provides a cooling effect on the panels which improves their efficiency of electric generation.
While this might sound great, can energy efficiency be promoted in a developing country like Africa with so many other priority areas that need to be addressed? The answer is yes – as sustainability needs to be seen as a key development priority along with education, health and jobs. Given the ongoing capacity constraints on the national grid it is something that cannot be ignored – and may even play its part in creating jobs and providing healthier lifestyles.
For example, the South African Government has committed to carbon reduction targets of 34% from 2010 levels by 2020. With buildings, either in their construction or operations, currently contribution 40% of carbon emissions in built up or urban areas, this will be no easy task.
Fortunately, through initiatives such as the Green Star SA ratings knowing how to design and build sustainably has become significantly easier than even a couple of years ago. And while this more efficient design has become a matter of course with new buildings, existing ones and the need to 'convert' them cannot be overlooked.
While strides can be made in tackling the resource challenges from a public sector perspective, so too can private sector play its part – specifically from a development point of view. Another good example is in Namibia, where WSP Group Africa was involved with the FNB Namibia Head Office building development, however to ensure they meet the standard criteria they participated in the creation of a local Green Building Council (GBC) as local conditions differ in Namibia to that of South Africa and as the client wanted a building aligned to a Green Star certification – they assisted in the creation of these infrastructures.
Cynics might argue that refurbishments are costly and do not make economic sense. Yet, there is a strong business case for implementing energy efficiency measures. It is important to evaluate the full life cycle costs of any intervention. If specified and installed correctly, systems and structures can produce a sustainable return on investment that can reduce energy consumption between 20% and 70% and gain long-term revenue through this investment.
Additionally, there are a number of ‘green funds’ and tax incentives that can contribute to making the business case more appetising. Finally, one needs to consider issues other than the pure financial viewpoint when considering the net benefit of a particular intervention, including energy and water security (i.e. being able to continue your business operations in the event of a supply fault), mandatory corporate reporting (e.g. King III), marketing value (being seen as a leader in terms of sustainability) and employee benefits (improved workplaces and productivity). The ongoing operational savings of these do pay back the capital outlay fairly quickly. Given that the lifetime of a building is many decades, the savings will continue to be relevant (and be worth more as energy prices escalate) for many years.
As such, there will be a continued upward trajectory where the industry in various regions will increasingly see this becoming the norm, as adapting to a sustainable building environment impacts on a positive economic and social outcome. Long-term operating costs are lowered via reduced energy consumption, reduced emissions, improved water preservation and management.