Chill wind blows clean away
The government has been looking at measures to reduce South Africa’s dependence on fossil fuels and to have renewable energy account for a greater percentage of the electricity generated.
The Eastern Cape and Western Cape have been earmarked as ideal locations for wind farms.
Wind energy is in line with government’s plan to lower its carbon emissions.
Two wind farms in the Western
Cape—Klipheuwel and Darling. Klipheuwel is serving as pilot project for Eskom to determine the feasibility of wind farms to provide electricity for the country.
The Darling wind farm, which has an annual output of 13MW, was the first independent wind-power generator connected to the grid. It signed a power-wheeling agreement with Eskom to fulfil a 20-year power purchase agreement with the Cape Town municipality. Several companies, such as Macquarie, Innowind, Investec, Mainstream and ENE, have expressed interest in developing wind farms with generating capacity of up to 1GW a year.
G7 Renewable Energies has said it will develop five new wind farms—at Lamberts Bay, Klawer,
Roggeveld, Witberg and Richtersveld—in the next two years, although this is unlikely. Feasibility studies to determine the suitability of areas or sites for wind farms take a long time and have high input costs.
Wind speed has to be measured at different heights as well as the average amount of wind a
year. The areas must also be close to existing transmission lines and substations for easy integration into the Eskom network.
Currently the lead times to import turbines are lengthy and the development of the farm itself is a drawn-out process. Although wind power is generally environmentally friendly it poses a
number of environmental drawbacks. Noise pollution is a major concern and the windmills pose a danger to birds.
Decreasing bird numbers have been known to result in an increase in insects, which brings its own set of problems. These hazards require environmental impact assessments to be done, which result in further delays in implementation.
One of the challenges of wind farms is the initial capital outlay. For a wind farm to generate 200MW, approximately 100 turbines will have to be erected, each roughly 30m high and no less than 500m apart. Other infrastructure includes power cables and roads, which require routine maintenance.
Companies are looking at developing wind farms up to five times this size, rendering start-up capital at billions of rands. Although Eskom’s installed generation capacity is standing at 40GW, the current National Integrated Resource Plan (NIRP) allows for only 200MW of renewable energy a year. It is hoped that this allocation will be increased in the new IRP2010, which is unlikely until it becomes more financially viable for Eskom to purchase more.
The difficulty for independent power producers (IPPs) is that the National Energy Regulator of South Africa (Nersa) has issued its renewable energy feed-in tariff (Refit) for wind at R1.20 a kWh. But Eskom is the sole buyer of renewable energy and it can generate power from coal at 60c a kWh and, without the steep tariff increases it has been pushing for, it is near impossible for Eskom to afford to buy wind energy.
It appears to be wary of signing any power purchase agreements that will bind it to an unaffordable rate for an extended period. Because of this, IPPs cannot obtain external funding from agencies such as the World Bank and the Development Bank of Southern Africa. Paul Runge, managing director of Africa Project Access, works with donor finance institutions and other funders: “Funders are straining at the leash to fund wind-power projects.
It has become part of government planning throughout Africa but the problem is that the countries need to organise their own regulatory framework before anyone will invest.” Evolution One Fund is a South African fund manager that focuses particularly on renewable, sustainable and environmentally friendly energy. “There is no shortage of funding available,” says Runge. “The difficulties lie in identifying the viable projects. Funders want to know who will ultimately be purchasing the energy.”
It is projected that the price of wind power will drop significantly over the next few years as the major producers of wind turbines, including China (which produces 40MW of wind energy annually and is growing its installed capacity to 100GW a year) and Germany, start to sell their surplus produce at significantly reduced prices. It is also possible that turbines could be made more cheaply locally.
IPPs could sell energy to other buyers, such as municipalities, but the price would have to be negotiated—the R1.20 a kWh has been set for Eskom only. The wind-generated power would have to be transmitted through Eskom’s lines, which means a power-wheeling agreement would have to be signed, which would also increase costs.
Currently wind power is far from sustainable in South Africa. Being sold to Eskom at R1.20 a kWh, it would cost the consumer about R1.50 a kWh, almost double that of the cost of coal-produced energy. Until input costs drop to either on par with or below those of fossil fuels, it is unlikely that wind power will be a major source of energy for ordinary South Africans. And although wind power generation is included in the national planning process, it is by no means a short-term solution to the needs of the country.
Energy-wise solutions for stadiums
ABB’s energy-efficient solutions are found in most of the Fifa World Cup stadiums. For the two main stadiums, Soccer City and Green Point, ABB delivered and installed 26 vacuum-cast, coil, dry-type transformers to ensure a reliable and efficient power supply. Fourteen dry-type transformers in the 630kVA (kilovolt amperes) to 1 000kVA range were supplied to Soccer City and 12 1 200 kVA dry-type transformers to Green Point.
The supply included 12kV AIS UniGear type switchgear to the stadium and ABB GIS ZX1.2 indoor MV switchgear for the Mouille Point substation that supplies power to the stadium. Because safety was crucial, ABB’s vacuum-cast transformers, which are self-extinguishing and suitable for indoor and outdoor use, were ideal for the application.
In addition ABB is using its technology to maintain Cape Town’s power grid. Sophie Roch-Bernhard, the local business unit manager for substations at ABB South Africa, says the switchgear is part of a three-year agreement with Cape Town, including medium-voltage switchgear, Scada and power products for nine substations.
ABB South Africa installed 78 LV variable-speed drives ranging up to 55kW for heating, ventilation and cooling at Green Point stadium. The drives help control air quality and movement in fire-escape tunnels. At Nelson Mandela stadium, ABB installed 86 drives, the largest being 37kW in size.
The company also supplied drives for Mbombela, Moses Mabhida, Soccer City, Royal Bafokeng, Peter Mokaba and Pietermaritzburg stadiums. For the Gautrain ABB supplied traction solutions, substations, traction transformers and traction motors to power the line and trainsets.