The Zambezi River Basin is well known for its diversity in energy resources: renewable, non-renewable and new energy technologies. Renewable energy sources include biomass, hydropower and ethanol. Non-renewable includes thermal power, coal, petroleum and natural gas. New energy technologies are solar and wind. Renewable energy can be used repeatedly, given appropriate management and conservation. Non-renewable energy has a fixed supply, which will eventually be exhausted.

RENEWABLE ENERGY

Biomass
About 74 percent of the total energy requirements of the eight Zambezi River Basin countries comes from biomass; fuelwood, charcoal, and plant residues. Biomass is used for domestic purposes (cooking and lighting) and in agriculture for curing tobacco (especially in Malawi, Mozambique, Tanzania and Zimbabwe). It is also used for brick manufacturing; lime production; fish smoking; and coffee and tea-drying. While the amounts of biomass energy derived from the basin by each country are not readily available, information on fuelwood consumption compiled for six of the basin countries by the SADC Forestry Sector Coordination Unit in 1997 indicates that all of them derive most of their energy needs from biomass

Hydropower generation
Electricity power generation which is as a non-consumptive water use, involves directing water to turn turbines, thereby producing electricity. The estimated hydropower potential of the ZambeziRiver is 20,000 megawatts (MW) of which about 4,620MW has been developed. Of the 4,620MW available, about five percent is in Malawi, 45 percent in Mozambique, 36 percent in Zambia and 14 percent in Zimbabwe. A summary of some hydropower developments is shown in box 1.

The Cahora Bassa hydropower plant, with an existing installation capacity of 2,075MW, is the largest in SADC, followed by the Inga in the Democratic Republic of Congo, with 1,771MW. Under current arrangements, Zimbabwe can import up to 400MW per month and the remainder is consumed by both South Africa and Mozambique.

Potential hydropower plants with a total installation capacity of 12,892 MW have also been identified in the basin as follows: nine in Angola; seven in Malawi; 12 in Mozambique, including the giants, Cahora Bassa II, Mepanda Uncua and Chemba which have installation capacities exceeding 1,600MW each; 10 in Zambia, including the giants, Batoka (1,600MW), Devil’s (1,240MW) and Mupata (1,000MW) gorges; and four in Zimbabwe, also including Batoka, Devil’s and Mupata gorges.

Ethanol
Malawi is the only country utilising the basin’s resources to produce ethanol, which is used to blend petrol. Ethanol is produced from sugar molasses at Dwangwa Estate Plant on the lakeshore. However, other basin countries, for example, Zimbabwe, produce ethanol outside the basin.

ENVIRONMENTAL IMPACTS OF RENEWABLE ENERGY

Deforestation, leading to soil erosion and ultimately land degradation and siltation, is the main problem associated with biomass energy utilisation in the basin. As such, more environmentally friendly energy alternatives such as hydropower (at micro level), wind and solar should be promoted, especially for the rural communities.

There is also need to make existing technologies more energy efficient. Examples are the tsotso stove and the recently redesigned brickmaking kiln which can lead to huge savings in woodfuel.

Wood fires contain many poisonous chemicals, and can be a locally significant source of air pollution. However, virtually all the basin countries are involved in programmes aimed at reducing heavy dependence on woodfuel, particularly in rural areas. Afforestation and environmentalawareness programmes are also being undertaken within basin countries by the governments, NGOs, donors, the private sector and the public to ensure sustainable use of woodfuel.

Damming rivers for hydropower plants has widespread negative environmental impacts. These include the displacement of people and animals; burial of heritage sites, plants and animals; depletion of wetland habitats and aquatic life; increases in water-borne diseases; sedimentation, siltation and siltation-induced flooding; and loss of irrigation water downstream. Lake Kariba alone displaced over 58,000 people about 40 years ago while the Cahora Bassa in Mozambique forced the relocation of about 25,000 some 25 years back. The animals and plants were not spared either. In addition, buried biomass and flood debris decompose, emitting methane, one of the greenhouse gases (GHGs) associated with global warming. Molasses, from ethanol production, threaten the environment in that it is sometimes disposed of into watercourse systems.

To minimise the negative impacts, legislation binding developers to undertake Environmental Impact Assessments (EIAs) before embarking on such environmentally sensitive development projects are inevitable. In addition, remedial measures outlined in EIA reports must be fulfilled. Although the basin countries have made great strides towards establishing national EIA laws, the benefits of conducting EIAs are not being fully realised.

NON-RENEWABLE ENERGY

Thermal power generation
Thermal power is electricity produced by burning fossil-fuels, including coal, coal-bed methane, natural gas and diesel to produce steam to turn turbines. However, it is coal that is mostly utilised by the basin countries in thermal power production. As such, once coal is exhausted, the thermal plant seizes to produce electricity. The major thermal plants are located in Zambia and Zimbabwe.

Coal
Virtually all known, exploitable coal reserves for: Malawi (three million tonnes); Mozambique (2,422 million); Zambia (69 million); and Zimbabwe (1,187 million) are found in the Zambezi Basin (1988 estimates). Angola and Namibia do not have known coal deposits. Coal reserves within the basin are utilised mostly for thermal power generation, domestic uses such as cooking and heating; industrial uses such as smelting and making chemicals; and commercial uses such as tobacco curing and railway traction. Coke oven gas is also produced from coal-burning and is used in industry, and of late, has replaced diesel as a start-up in thermal power generation plants.

Petroleum and natural gas
Although there are no petroleum plants in the basin, indications are that the thick extensive sedimentary rocks in the basin have a potential for petroleum deposits and natural gas. This has led to extensive exploration by oil companies in Malawi, Mozambique and Zimbabwe.

ENVIRONMENTAL IMPACTS OF NON-RENEWABLE ENERGY

Coal-mining and use impact on the environment in various ways: fine dust, gases and smoke pollute the air while the excavated spoils piled up in dumps are unsightly. Open-cast coal mines such as the Maamba in Zambia and Wankie in Zimbabwe experience problems of spontaneous combustion. This, coupled with coal burning in thermal power plants, lead to air pollution from sulphur dioxide. The gas significantly affects asthmatic patients, resulting in severe coughing and corresponding effects. The public in Kitwe and Mufulira in Zambia has in the past complained of breathing problems due to sulphur dioxide pollution.

When acidic gases such as sulphur dioxide combine with rain, the result is ‘acid’ rain. Acid rain damages plants and soils. It even corrodes vehicles and steel roofing. Coal mining in the basin countries contributes thousands of tonnes of sulphates to the atmosphere annually.

Brack water, which is extremely rich in natural sulphates derived from the sulphur and alkaline metals in the coal layers, sometimes flows into streams. Mine dumps too, are washed away into watercourses during storms, leading to waste pollution from sediments and dissolved harmful substances. In areas of extensive domestic use ofcoal, morning smoke greatly reduces visibility, increasing the chances of road traffic accidents. Coal-fired power stations also consume large quantities of water needed in the cooling process.

NEW TECHNOLOGIES

Solar cells are used to tap light from the sun which is converted into electricity. This technology (commonly used for lighting, and low-voltage electrical appliances such as radios and television sets) has been welcomed by rural communities throughout the basin and beyond. In Zimbabwe, alone, about 10,000 solar panels have been installed mainly through the Global Environment Facility (GEF) Solar Project. In Botswana, solar energy is also widely used, including for water desalinisation.

Windmill pumps are utilised by rural commercial farmers to pump water for livestock-watering and to a limited extent, supplementing irrigation water. A pilot project in Manicaland Province, Zimbabwe, by Regional Environment Organisation (ZERO) has shown that it is possible to generate electricity even at low wind speeds using specially designed turbines.

The greatest threat to the environment is the disposal of solar panels and batteries that may lead to pollution, particularly from battery acids.

THE POWER BEHIND COOPERATION

Today, sustainability in energy needs goes beyond the basin countries. Platforms for SADC cooperation in energy have been set through the 1982 and 1992 policy documents entitled "Towards an Energy Policy for Southern Africa" which were translated into the SADC Protocol on Energy signed by all member states in 1996.

Electricity has been shared between the DRC and Zambia as early as the mid-1950s. Today, the Kariba power plant is jointly operated by Zambia and Zimbabwe through the Zambezi River Authority (ZRA) established in 1987 , succeeding the Central Africa Power Corporation. The erection of a 340-km long, 220 kilovolts (kV) transmission line between Bulawayo (Zimbabwe) and Francistown (Botswana) is facilitating the export of electricity, mainly hydropower from Zambia to Botswana. Recently, the ZRA signed a contract with ESKOM (South African Power company) for the production and sale ofhydropower energy. A similar deal has been concluded with Mozambique, including a tripartite agreement between Mozambique, Portugal and South Africa for the rehabilitation of Cahora Bassa infrastructure. Zimbabwe has just begun importing about 400MW of power monthly from Cahora Bassa through the Songo-Bindura-Dema 420kV interconnector while negotiations for 30 percent stake in the Cahora Bassa Hydropower station were ongoing in May 1998.

Probably, the most notable achievement is the establishment of the Southern African Power Pool (SAPP) in 1993 which was signed by all SADC countries in 1995. The SAPP aims at providing electricity to all SADC countries in an environmentally sound manner and also focuses at drawing hydropower from the Inga Hydropower plant which has a potential of generating up to 100,000MW using the natural flow of the Congo River to turn turbines.

MORE INFORMATION CAN BE OBTAINED FROM:

SADC Energy Sector, Technical and Administrative Unit, CP 2876 or 16502, Luanda, ANGOLA Tel: 244-2-45288/43003	Ministry of Energy and Petroleum, P.O. Box 1279, Luanda, ANGOLA Tel: 244-2-345288 Fax: 343003 Telex: 4090 TUANG AN
Botswana Technology Centre (BTC) Private Bag 0082, Gaborone BOTSWANA Tel: 267-314161 Fax: 374677 Telex: 2929 TECEN BD	Ministry of Energy and Mining, Private Bag 309, Lilongwe 3 MALAWI Tel: 265-781255 Ministry of Industry and Energy, 25 de Setembro Avenue, Maputo, MOZAMBIQUE
Ministry of Mines and Energy, Private Bag 13297, Windhoek, NAMIBIA Tel: 061-226571	Ministry of Water, Energy and Minerals, P.O. Box 9153, Dar-es-Salaam, TANZANIA Tel: 255-51-49113 Telex: 57402
Department of Energy, Box 3055, Lusaka, ZAMBIA Tel: 260-1-292165 Fax: 252339 Telex: MPTC ZA 41680	Zambezi River Authority, P.O. Box 30233, Lusaka ZAMBIA Tel: 260-1-228401 Fax: 227498
Department of Energy, P.O. Box 7758 Causeway,Harare ZIMBABWE Tel: 263-4-791760-9 Fax: 721967 Email: doezim@harare.iafrica.com	Zimbabwe Electricity Supply Authority (ZESA), P.O. Box 377, Harare, ZIMBABWE Tel: 263-4-793033-9