FEATURES
Solar panels are gaining traction in a lot of affordable housing projects .
" If we provide thought through homes and communities and educate the community , we can greatly reduce our energy requirements "
“ Encouraging natural ventilation and daylight through the correct window to wall ratios can cool the homes in summer and make interior spaces more liveable . The application of semi reflective or lightly coloured roofing material coupled with insulation to ceiling voids , greatly reduces heat gains in summer and heat loss in winter ,” he explains .
Other ways of designing the home to achieve sustainability include insulated solar geysers with electrical backup this ensures that the home will have hot water while reducing the need for electrical water heating . Water can be collected from roof gutters for flushing toilets and watering gardens or in times of water shortages . Low flow sanitary fittings are affordable and significantly reduce the demand on water supply .
Luke Osburn from the Council for Scientific and Industrial Research ( CSIR ) Built Environment , says that lighting only consumes about 11 % of the energy used in a residential environment . “ Through conscientious design of the lighting systems , the lighting load can be reduced by more than half ,” he says .
He suggests that fluorescent tubes should be used where possible as they use roughly a quarter of the power that incandescent bulbs require to produce the same amount of light .
“ Because the fluorescent tubes are more energy efficient than the incandescent bulbs , they also produce significantly less heat which means that a smaller heating , ventilation and air conditioning ( HVAC ) system is required and less energy is required from the HVAC system to maintain a comfortable temperature and working environment . A variety of fluorescent tubes are available and care should be taken that the most appropriate fluorescent tubes are installed for the given application ,” he advises .
Light-emitting diode ( LED ) lighting can be used throughout the home to save on electricity . LEDs consume less power and thus last longer .
“ LED is easier to recycle because they are made with a Restriction of Hazardous Substances ( RoHS ) substance that makes it easier to dispose . With LEDs you are consuming less power on the grid ,” says Fazil Ogle , MD of OPS360 .
Normal energy savers uses 11kW , while LEDs uses 5kW . Investing in solar and other means gives you a saving of about 2.5 less kW . “ A typical three-bedroomed home that just runs off solar with LED will cost about R30 000 to
R55 000 depending on how you use it . If you don ’ t use LEDs , it may cost around R80 000 to R120 000 .”
GOING GREEN ON A BIG SCALE
“ On a macro scale , town planning plays an important role in making a community as opposed to another standard housing project ,” says Naicker .
Some ways that this can be done is with the inclusion of recreational spaces . These can reduce stress and encourage communal growth . Storm water management across the site reduces the risk of flooding and the water can be collected and used within the recreational spaces or in times of drought .
“ Communal recycling facilities and waste management can stimulate job creation and reduce waste going to already stretched landfill sites . Solar powered street lights save on electrical supply and make streets safer ,” he says . Locating housing projects close to public transport nodes and efficient movement networks within the communities makes commuting easier and safer .
Matt Jackson from the Johannesburg Development Agency ( JDA ) says that transit-oriented development ( TOD ) coupled with affordable housing are bankable . “ Simply put , TOD is a city development approach which intensifies and diversifies land use along public transit routes and stations precinct ,” he says . He says that the Yeoville suburb in Johannesburg is an area that is doing this well .
In Cape Town , Michael Alton describes a growing trend of heat pump installations .
“ The introduction of lower capacity integrated heat pumps ( 150l ) by HydraTherm ( compared with competitive brands that use 200l and 300l tanks ), is technology that is starting to gain traction in the affordable housing sector in Cape Town . An integrated heat pump is a solution in which the tank ( geyser ) and heat pump are combined into one unit ,” he says .
A heat pump is an energy-efficient water heater that removes free heat energy from the surrounding air and transfers this to the water in your geyser .
Affordable , low capacity domestic heat pumps ( 3.8kW or less ) can be combined with an affordable geyser ( 100l or 150l ) to create an efficient means of heating water . “ This will save the occupants of the home 70 % of the water heating costs of a traditional geyser element ,” states Alton .
22
NOVEMBER - DECEMBER 2017
AFFORDABLE
SA HOUSING