International wind farm developers keen to invest in South Africa will now be able to make use of a large-scale wind map to identify areas for wind exploration. 

This came to light after the country’s Department of Energy (DoE) recently launched the Wind Atlas for South Africa (WASA) high-resolution wind resource map which covers all nine provinces of South Africa.

WASA is one of the projects of the South African Wind Energy Project (SAWEP), with the DoE as the executing partner. SAWEP is funded by the Global Environment Facility through the United Nations Development Programme country office providing support. The South African National Energy Development Institute (SANEDI), a state-funded energy research company reporting to the DoE, manages the SAWEP project.

The project came about following a review of wind energy resource studies (2003) that was undertaken by the then Department of Minerals and Energy as the accuracy of predicting wind energy with available wind atlases was very poor. For example, many of the weather measurement stations used in these studies are too close to buildings and other obstacles that obscure measuring the real wind resource. These weather measurement stations are also typically at lower heights, which results in extrapolation errors in predicting the wind resource at a typical megawatt (MW) wind turbine with hub height 70m and higher.

Based on the findings, the following recommendations put forward:

- Obtain a more accurate basis for determination of the wind resource at high potential regions in South Africa and establish a network of long-term, high-quality measurements in these high-potential regions. These measurements can be used as long-term references for feasibility studies of wind power projects as well;

- Erect masts that are at least 30 metres and far from obstacles (trees and buildings). The maintenance and data check of these measurements are also of major importance; and

- Ensure measuring sites are localized by wind energy experts using the present wind atlases in combination with the knowledge of the orographic enhancement of the wind across hilly terrain and/or digital description of the terrain and flow modeling programme.

In a nutshell, the map depicts the local surface wind climate (mean wind speed, mean wind power density) which a wind turbine or wind farm would operate in. It also provides statistics that enable predictions, such as annual energy production of a wind turbine and expected capacity factor, i.e. predicting the bankability of the project with physical wind measurements only to be undertaken for bankable projects to confirm the predictions, thereby saving time and money.

According to Andre Otto, WASA project manager at SANEDI, the map will level the playing field for both small and large scale investors as “it will help them to identify potential wind development areas and estimate potential income without costly and time-consuming wind measurements, which many small players cannot afford”.

The DoE’s acting director-general emphasised the importance of accurately determining the availability of wind.

“As we continue on our ambitious renewable energy path, wind energy remains an integral part of this goal. However, it would be difficult to plan thoroughly for the increased uptake of wind energy if one does not have certainty on wind resource availability.
“Therefore, the need for reliable, accurate and representative data on wind is critical. It is for this reason that the Department of Energy undertook to complete WASA,” he said.

The introduction of WASA is good news for international renewable energy companies, such as Italy’s Enel Green Power and Building Energy which bid for wind construction projects under South Africa’s Renewable Energy Independent Power Producer Procurement Programme (REIPPPP). Enel has already been awarded a total of five wind projects for 700 MW through the programme.
The REIPPPP, which aims to secure renewable energy from independent power producers, is part of the South African government’s Integrated Resource Plan which aims to double the country’s electricity capacity using a diverse mixture of energy sources such as coal, gas, nuclear and renewables. To date, the REIPPP has resulted in the procurement of 6.3 GW of new renewable energy capacity, with 3.9 GW already online.