“It is important to note that there is a lot of ‘greening’ that companies can do with existing buildings.”
Going ‘green’ is now mainstream for cost-efficient building design
A ‘green building’ is defined as one that is energy efficient, resource efficient and environmentally sustainable. It incorporates design, construction and operational practices that significantly reduce or eliminate the negative impact of development on the environment and occupants.
Until recently, a South African company that built their offices using green building principles may have done so either for altruistic purposes or to make a statement for their brand.
However, rapidly rising energy costs are forcing companies to look for ways to drastically reduce their electricity demand. Taking into account the 8% per annum price increase for electricity over the next five years, cost of electricity will have risen by 156% over a ten-year period from 2008 to 2018. As a result, electricity costs have and will continue to become an increasingly significant cost driver for most companies.
Green buildings provide sound methods for reducing electricity consumption. Energy consumption within office buildings tends to be largely driven by heating, cooling and lighting. Passive solar design (window glazing, insulation and other elements that are designed to collect, store and distribute solar energy in winter and reject the same solar heat in summer) can reduce buildings’ heating requirements by 20% to 40%. Proper shading can reduce the cooling requirements of a building by the same percentages, while natural ventilation can replace 60% of the ventilation requirements. The utilisation of ‘free energy’ in the form of sunlight can reduce the need for artificial lighting by 35% to 75%. The energy-saving potential within heating, cooling and lighting has been echoed by the Green Building Council of South Africa (GBCSA), which claims that savings of as much as 50% are possible.
Not unlike energy, the demand on water resources is also steadily rising. South Africa is one of 30 most water-stressed countries in the world).1 This situation is likely to be exacerbated by a reduction in supply, as predicted under future climate scenarios. Adding to this is the continuous rise in urbanisation that will place increased stress on an already ailing infrastructure. According to a survey on the water use of South African companies, 71% of the 30 JSE-listed companies that responded had already experienced financial loss because of water issues.2 This provides strong motivation for reducing building demands for municipal water, as well as for the sustainable consumption and management thereof during the building process and in the general operation of the building.
Supporting South African companies to ‘go green’
Misconceptions around the cost of green buildings have deterred many companies from adopting green building principles. We contend that these misconceptions have been largely created by professionals in the building environment who have been known to overestimate the costs of green design and construction by more than 300%.
Despite this potential stumbling block, green building practices and techniques are becoming mainstream in South Africa – according to GBCSA CEO Brian Wilkinson. Growing numbers of members of GBCSA, as well as the increasing number of green buildings, attest to this. The number of Green Star SA certifications has doubled every year since 2009 year-on-year and GBCSA’s goal is to reach 60 certifications by the end of 2013.3
This shift has been assisted by government, which has high expectations of the private sector to lead the way in this space. South Africa’s first compulsory national standard for energy efficiency in buildings (SANS 204) was passed in November 2011. This signified a massive transformation, as no legislation enforcing green initiatives in the building environment was previously in place.
The development of the Green Star SA rating system (with GBCSA as the official certification body) is largely recognised as being responsible for further accelerating the trend towards green buildings. The launch of this assessment aid has seen a race among South African companies competing to win favour among clients and investors hoping to see the private sector making the shift towards a greener economy.
Sidebar: The GBCSA’s Green Star ratings are based on the Australian Green Building Council’s rating tools and assess buildings according to eight categories, namely management, indoor air quality, energy, water, transport, materials, land use and ecology, and emissions.
Eskom is also playing its part in making the shift towards ‘going green’ more financially attractive for businesses. It has developed a range of highly accessible financial incentives for a broad range of applications.
The top-rated South African green office buildings
Innovative trends in green buildings have been implemented in two of South Africa’s highest rated buildings, namely the Vodafone Group building in Midrand (its six green stars making it the greenest building in Africa) and the Aurecon office building in Century City, Cape Town (the first building in South Africa to earn five green stars.
The Vodafone building incorporates reused or recycled demolition material from the site, relies completely on renewable energy, uses photovoltaic panels to reduce the amount of wood and structural material required for the roof, and has a mechanical air conditioning, heating and ventilation system designed to deliver fresh air to the building. The latter is particularly relevant, considering that the heating, ventilation and cooling of a typical commercial office space accounts for between 30% and 50% of the total energy load.
Bearing in mind that up to 63% of energy consumption in a building is associated with the HVAC (heating, ventilation and air conditioning) system, Aurecon designed an energy-efficient HVAC system that would have a huge impact on reducing the overall energy consumption of the building. These technologies include a chiller that is able to operate on part loads from as low as 10%. An induced draft cooling tower is also used which, as opposed to a forced draft, has a counter flow of water and air resulting in increased heat transfer efficiency. The air handling units include variable air volume (VAV) technology, which has the advantage of operating at a predetermined temperature and air flow rate. Apart from the HVAC system, an atrium and an additional light well make excellent use of natural light, further reducing electricity consumption and thus operating costs.
Cost and savings
Although only some design elements of a green building will generate immediate savings, the development costs thereof should be seen as an investment in managing future cost drivers, particularly with utility costs set to escalate.
It is important to note that there is a lot of ‘greening’ that companies can do with existing buildings. While some of the changes will require investment, others such as raising employee awareness around energy and water usage can cost companies next to nothing and yet will yield savings now and into the future.
Finally, it has been estimated that cities are responsible for consuming three-quarters of the world’s natural resources. This is set to rise as the proportion of the global population living in urban areas increases to an estimated 70% by 2050.
It has been shown that greening urban infrastructure not only uses fewer natural resources but also sustains economic growth, reduces poverty and improves well-being. These are national and global benefits that cannot be ignored.
1 World Wide Fund for Nature, Living Planet Report 2012.
1 CDP’s water program: South Africa Report 2012: recognising the strategic value of water, available at https://www.cdproject.net/CDPResults/CDP-SouthAfrica-Water-Report-2012.pdf.
2 First Green Star rated building for Paarl – 31st certification for SA, Green Building Council News, 6 June 2013, available at http://www.gbcsa.org.za/news_post/first-green-star-rated-building-for-paarl-31st-certification-for-sa/.
Author: Gina Zietsman is a research analyst at the Moss Group and Nicky van Hille is the founder of the Group.