We still rely heavily on coal to generate electricity, but with an ageing fleet of coal-fired power plants we should perhaps start to tap into our abundant offshore wind energy resources to help address future electricity shortages.
“If we were to install wind turbines at different depths off the KwaZulu-Natal and Western Cape coast, they could potentially supply approximately 15% and 800% of South Africa’s annual electricity demand,” say Gordon Rae and Dr Gareth Erfort from the Department of Mechanical and Mechatronic Engineering at Stellenbosch University.
They used geographic information system methods to do the first comprehensive assessment of South Africa’s offshore wind energy resources and to identify the most suitable regions for the development of wind farms. Their assessment included marine protected areas sourced from the World Database of Protected Areas, which is the most comprehensive data-base on terrestrial and marine protected areas. The researchers say they included marine protected areas in the study to create what they call “no-go zones”. “It was important to include these no-go zones as they illustrated to us what portion of the exclusive economic zone would be inaccessible to offshore wind energy from an environmental perspective.”
The findings of their study were published recently in the Journal of Energy in southern Africa.
The researchers say their assessment showed that the most suitable regions for the development of offshore wind energy are Richards Bay (within the 10 km coastline buffer & approximately 15 km offshore south of Richard Bay), Durban (within the 10 km buffer & approximately 25 km offshore of KwaDukuza) and Struisbaai (within the 10 km buffer zone & approximately 15 km offshore).
“Our study revealed that South Africa has an annual offshore wind energy production potential of 44,52 terawatt hours (TWh) of electricity if wind turbines were to be installed in shallow waters (depths of less than 50 m) and 2 387,08 TWh with wind turbines in deeper waters (depths less than 1 000 m).
According to Eskom, a typical South African household uses about 30 kilowatt hours (KWh) per day or 10 950 KWh per year, which means that 44,52 TWh could technically power approximately four million average households annually. Similarly, 2 387,08 TWh could power roughly 218 million average households per year.The full article is for subscribed members only. To view the full article please subscribe. It’s FREE!Log In Register