Power Generation

Traditional sources of power generation such as coal, are water-intensive, while hydro-power allows the water to be re-used downstream. However, most large scale hydroelectric projects require the building of dams which alters the flow significantly and large areas of land are flooded, including wildlife habitat and vegetation causing significant environmental impacts. Small scale hydro projects, such as run-of-river, divert only a portion of a river without any flooding or need for reservoirs, therefore, the environmental impacts are lower in comparison.

The source of electricity in each riparian country in 2006 according to World Bank World Development Indicators is as follows (World Bank 2010):

• Botswana - 99 % coal
• Mozambique - 99 % hydropower
• South Africa - 93 % coal, 5 % nuclear, 2 % hydropower
• Zimbabwe - 43 % coal, 57 % hydropower

Botswana and South Africa are heavily coal dependent for their electricity needs, while Mozambique is solely reliant on hydropower and Zimbabwe is equally split between coal and hydropower on a country-wide basis.

Water Demand: Conventional Power

In 2000 it was estimated that 18 % of water usage was in the mining and energy sector in Botswana (Swatuk and Rahm 2004). This consisted of one coal fired power plant and about half a dozen mines. It is estimated by 2010 that the water demand of the energy and mining sector increase to 22 % in Botswana (Swatuk and Rahm 2004). One planned power project, Mmamabula, is in the Limpopo River basin. This project involves the development of coal fields and associated power stations and has a power generating capacity of 2 500 MW (ADB 2008).

As noted in Water Use & Allocation, water use for power generation in the basin is only reported in South Africa, accounting for approximately 7 % of water demand (LBPTC 2010). Within the Crocodile (West) and Marico WMA there are two municipal power stations in Pretoria and one near Kempton Park (DWAF2003c). Some of the largest thermal power generating stations in the world are located in the Olifants WMA in the industrial centres of Witbank and Middelburg and near Phalaborwa. Power production is significant in the Limpopo WMA due to the Matimba power station at Lephalale which is the largest directed dry-cooled power station in the world. No power generating station is located in the Luvuvhu and Letaba WMA.

Aquatic ecosystems in the Waterberg area of South Africa (within the sub-catchments of Mokolo and Lephalala) may be adversely affected by proposed coal-fired power stations proposed in the area (Shirley 2009). Increased atmospheric deposition could exert significant pressure on the existing ecosystems within the Limpopo River basin.

Although, there is a planned coal fired power plant in the Tete province of Mozambique (northwest of the Limpopo River basin), there are no known power developments in the Limpopo River basin (CMEN 2010).

No known power plants are present in the Zimbabwe portion of the Limpopo River basin.

Water Demand: Renewable Power

In Botswana, from 2004 to 2008 there was policy reform in place to achieve energy self sufficiency and manage efficiency and access. The government's strategy included promoting the policy of renewable energy by using solar for power generation and water heating where economically feasible (ADB 2008).

Although, the largest hydrolelectric scheme in Southern Africa is in Mozambique (Cahora Bassa dam on the Zambezi River), there are no known sources of renewable energy power generation in the Mozambique portion of the Limpopo River basin.

South Africa has a large potential with renewable resources to harness this energy to meet energy demands in the future (DME 2003). In 2003, the Department of Minerals and Energy (DME) published a White Paper on Renewable Energy Policy, which set a target of 10 000 GWh for renewable energy contribution to final energy consumption by 2013. This target is to be produced mainly from biomass, wind, solar, small scale hydro and non-grid technologies such as biofuels and solar water heating (DME 2003). As noted on the figure below, good to excellent hydro power potential in South Africa is centred in the southeast, while the potential in the Limpopo River basin has limited areas on the east side of the basin with poor to acceptable potential (DME et al. 2001).

At the northern edge of Zimbabwe, bordering with Zambia, outside of Limpopo River basin, Zimbabwe has signed an agreement with China's Sinohydro to expand its Kariba hydro plant (Daily Nation 2010). No known hydroelectric power plants are present in the Zimbabwe portion of the Limpopo River basin.

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