|
With legislation in the pipeline demanding more energy efficiency in construction, Joburg has released a set of guidelines on building greening.
GUIDELINES to help architects, designers, planners and developers to produce more energy efficient buildings have been published.
The Design Guidelines for Energy Efficient Buildings guide was released in May 2009; it was compiled by the City and the Council for Scientific and Industrial Research and gives practical ways to construct buildings that have minimal energy requirements.
Some RDP houses in Cosmo City have solar water heaters
"The aim was to develop practical guidelines for the design and construction of energy efficient buildings in the city of Johannesburg, in order to promote the energy efficiency paradigm in the building industry prior to the introduction of national building regulations that address energy efficiency in buildings," says Linda Phalatse, the deputy director of climate change and cleaner production in the City's environmental management unit.
The guide emphasizes that building owners and developers should make their buildings energy efficient, as new legislation to be implemented by the City will require compliance.
According to the guide, buildings consume energy throughout their lifecycle - from construction to operation and then demolition.
It can be used by developers to maximise energy efficiency in their buildings, and to ensure challenging energy efficiency targets are set and met. Planners and urban designers can use it to help design more energy efficient settlements and cities. It is relevant for office and residential buildings, as well as a range of other structures.
Passive building
The guide focuses on passive environmental control, day lighting and the use of renewable energy like solar power. With passive environmental control, there is no need for mechanical heating or cooling; buildings take advantage of natural energy flows such as the sun.
The guidelines centre on the early design stages of a new building and what measures can be taken to ensure it is energy efficient. For example, it can be designed using west-, south- or north-facing strategies to maximise natural sources of energy such as the sun. Yet there is also information on making existing buildings more energy efficient, by looking at the usage of electricity, hot water, air conditioners and vehicles.
Greening buildings can cut operating costs, explains the guide. Building owners are advised to consider retrofitting their structures by checking the effectiveness of thermal insulation, windows and air ventilations. Using passive solar design is another solution. It makes use of natural light through windows and light wells. Energy efficient lighting systems and controls and solar heating systems can also be fitted into an existing building.
"Retrofitting is an investment that businesses should start looking into. They should start weighing their economies of scale by doing a cost-to-benefit analysis of their buildings and see how much they are currently spending on a normal building versus a retrofitted building," Phalatse says.
"Office parks can retrofit their buildings to be more energy efficient [by] changing lighting, ventilation and conditioning systems and use effective thermal insulation."
Homes can also be more energy efficient, she adds. "The geyser is the number one culprit ... Solar water heaters can replace current geysers and they can also replace old candescent lights with compact fluorescent light bulbs and unplug all electrical appliances [not being used] from the main switch."
Environmental impact
Developments are often built on greenfield sites; cutting down trees and other foliage for these developments reduces the capacity of the natural environment to absorb carbon dioxide.
South Africa produces the highest level of carbon dioxide emissions in Africa
South Africa produces the highest level of carbon dioxide emissions in Africa and has one of the highest levels of carbon emissions per gross domestic product in the world, according to a 2007 study, Energy Consumption versus GDP Based on Key World Energy Statistics from the International Energy Agency.
Increasing carbon emissions and a reduction in the ability of the natural environment to absorb carbon dioxide is leading to an accumulation of greenhouse gases in the upper atmosphere, trapping the sun's energy and thereby contributing to rising surface temperatures.
The main culprit is carbon dioxide (CO2), a by-product of burning fossil fuels.
It is predicted that temperatures will increase by 2°C to 6°C by the end of the century, according to a Synthesis Report on Climate Change compiled by the Inter Governmental Panel in 2007.
In Johannesburg, it is estimated that in the short term, temperatures may rise between 2°C and 3,5°C, according to Climate Change and Water Resources in Southern Africa, a report compiled by the Water Research Commission in 2005.
There is a direct link between buildings, carbon emissions and the ability of the natural environment to absorb carbon dioxide. Globally 40 percent of energy use, 17 percent of fresh water use, 25 percent of wood harvested and 40 percent of material used is attributed to the built environment, according to the 2008 Building Impacts published by the US Green Building Council.
More energy efficient buildings benefit their owners and tenants as they result in lower energy bills. While electricity costs in South Africa have been among some of the cheapest in the world, the guide points out, the price will rise rapidly as Eskom, the state-owned power supplier, seeks steep increases in its tariffs.
Save money
"Most important is to take into consideration the current economic crisis and projected electricity hikes and to start looking at ways in which one can be energy efficient," says Phalatse. "It's the simple things that count that can save you money and also save our environment, like changing your light bulbs, because inefficiency can also lead to the emission of greenhouse gases in the atmosphere."
Increasingly, legislation in South Africa will require more energy efficient buildings. The South African Bureau of Standards (SABS) is developing new standards on energy efficiency and municipalities such as the cities of Johannesburg and Tshwane are investigating the development of by-laws and incentive schemes to reduce energy consumption in buildings.
Phalatse says: "These guidelines are also aimed at informing the City's sustainable buildings by-laws that will be implemented in future."
Policies and standards supporting energy efficiency include the Energy and Efficiency Strategy and the White Paper on Renewable Energy, both from the Department of Minerals and Energy (DME). There also is a range of standards from the SABS covering everything from energy efficiency in buildings with artificial or natural environmental control to domestic solar water heaters.
According to the guide, the demand for energy outstrips the supply. This is expected to lead to further load shedding and power cuts, at least until 2014. Eskom and the DME are developing a range of incentives to reduce peak power consumption and support energy efficiency. These include subsidies of up to 100 percent for energy efficient lighting and solar water heating. There are details on Eskom's website and the DME's website.
Related stories:
|
