Kariba Dam on the Zambezi River between Zambia and Zimbabwe. Opened in 1959 its capacity is 1626MW. Picture from Wikipedia.

With 100,000 dams in the United States on almost every available site, producing 102,867 MW of electricity or 6% of total US electricity generation, the US is saturated with dams. There is now a strong movement in the US to remove dams. Africa, three times the size of the US with about 3 times more people, has only 35,339 MW of hydropower generation, but that amount accounts for 22% of Africa’s power production. More important is the fact that less than 10% of Africa’s hydropower potential has been tapped. Sub-Saharan Africa, where most of the major rivers in Africa are, already has plans to more than double its hydro production by 2030.

Hydropower has great attractions for Africa. First like coal, nuclear, and geothermal, hydropower is a base load power. Except for South Africa, which is highly dependent on coal and its two nuclear power plants (see my article on South Africa here), there are no other nuclear power plants in Africa and very few coal plants. Along with geothermal power in Kenya, hydropower is the main source of base load power in Africa. Moreover while hydropower cannot be turned on or off as quickly as gas/diesel peaker plants or electric batteries, the amount of energy being produced can be varied according to need much more easily than with coal or nuclear power plants. This is a major plus for African countries which have very low consumption of electricity. Dams also provide flood control, recreational activities on their lakes, and the possibility of irrigation. These uses are often complimentary but sometimes in competition.

Chart of the capacities of major existing and planned hydroelectric plants in Africa. The large grey circles are the capacity of planned hydroelectric plants, while the blue circles are existing capacity. The size of the circle indicates the magnitude of the capacity. The red lines are proposed regional power interconnections that will be needed for all this proposed electricity to be moved to the consuming nations. Note that this includes connections to Europe and the Middle East. Chart by Pinterest

Here is a list of the major dams built or under construction in sub-Saharan Africa. As can be seen in the large grey circles in the map above, the Congo River, the Blue Nile River, and the Zambezi River are the major large rivers with hydroelectric potential.

1. The Inga III dam in the Democratic Republic of the Congo (DRC) is under construction on the Congo River. It will have an output of 4,800MW. This is more electricity than the DRC needs. South Africa has an agreement to receive 2,400MW of the output. Details have not been agreed upon and so it is not clear if the price will be acceptable to South Africa. There is also a planned Inga IV dam (see article on this here) at the same site with a humongous output of almost 40,000MW making it two times the size of the Three Rivers Gorge dam in China, currently the largest in the world. The estimated $80 billion cost may be insurmountable. Who is going to use all this energy which is more than the current total hydropower output now of the whole continent?

2. Grand Ethiopian Renaissance Dam on the Blue Nile in Ethiopia with a planned 6,450MW of capacity is under construction. When completely in 2022 (?) it will be it the largest dam in Africa. It is 66% complete and supposed to begin producing some electricity next year. It will take 5 to 15 years to fill the reservoir behind the dam. See my article last week (here) on this dam. Since this output is much more than Ethiopia needs, much of it will need to be exported, but to whom and at what price?

3. The Stiegler’s Gorge Dam on the Rufigi River in Selous Game Reserve, Tanzania (see my report here) has just begun construction. Its capacity will be 2,115 MW.

4. The Aswan High Dam in southern Egypt on the Nile River which opened in 1971 has a capacity of 2,100 MW.

5. The Cahora Bassa Dam in Mozambique on the Zambezi River has a capacity of 2,075 megawatts and completed in 1974. The major part of the electricity produced is exported to South Africa.

6. The Gibe III Dam in Ethiopia has a capacity of 1,870 MW. Construction began in 2007 and was completed in 2016. My next week’s report will discuss the possibility that this dam will dry up Lake Turkana in Kenya.

7. The Kariba Dam also on the Zambezi River built in 1959 with a capacity of 1,626 megawatts delivers electricity to both Zambia and Zimbabwe. Each country has its own power station on the north and south banks of the river.

8. The Inga I and II Dams in the Democratic Republic of Congo (DRC) on the Congo River consists of two dams, Inga I (with a capacity of 351 MW) and Inga II (1,424 MW). They were commissioned in 1972 and 1982 respectively. The two dams were operating at only 50 percent of capacity because they had not been properly maintained.

There are negatives to hydropower in Africa. First although the water, like wind and sun, is free, the upfront costs of building a large dam is a major hurdle, needing substantial financing from the World Bank, the Chinese, or other sources. Usually there are delays in funding, cost overruns, and long years needed for construction.

There are also negative environmental downsides so that every major dam is opposed by environmental organizations – they usually lose. For an exception, read my report (here) on the cancelation of the Ndevu Gorge Dam in Zambia. Except for the Inga dams which use run-of-the-river electric generation, a dam needs a large lake behind it to impound the water to give a steady flow to the generators. This usually leads to negative environmental issues including the lack of water downstream from the dam. Since many dams also impound water for irrigation, the consequences can be dire – think of the Colorado River in the US which now never reaches the ocean.

People are displaced from the reservoir behind the dams. While they are supposed to be compensated, the amounts are usually low and sometimes the payments never reach them. Usually the displaced people have had no or little input into the decisions that are life important for them.

For a country that significantly depends on hydropower, another problem is drought. If there is insufficient rainfall and, with climate change this is going to happen more frequently, the power production is reduced and load shedding (planned, regular blackouts) are implemented to the detriment of users. After the recent drought in southern central Africa, this is currently happening in Zimbabwe and Zambia at the Kariba Dam. It may have to stop producing any electricity at all. 

Many of these large dams under construction or recently completed are producing much more electricity than can possibly be used in the country where the dam is sited. Each country seems to think that, even considering the expense of building high-voltage transmission lines, it can sell its surplus electricity to neighboring countries.

With the falling cost of wind, solar, and storage, is all this new hydropower in Africa necessary? I realized a long time ago that when a mega-project begins, it is almost impossible to stop its momentum. The dams I have mentioned above and others that are already under construction will more than likely be completed. Will they become “white elephants”? In some cases, yes.

Except in North Africa, wind, solar, and storage in Africa is still considerably more expensive than elsewhere in the world. The Lake Turkana wind farm in Kenya, the largest wind farm presently in Africa, is selling its electricity at 8 cents per kwh to Kenya Power. The Garissa Solar Power Station, also in Kenya, is selling its output at 5.5 cents per kwh. Old hydro dams are selling their output at 3 cents per kwh, but I have my doubts that these new projects can sell their electricity at that price. Then as wind, solar, and storage prices decline further, large hydropower will become more uneconomical.

A further advantage will be that many smaller wind and solar projects can be built quickly, with modest fiscal needs, in locations closer to where the energy will be used. In the long run, there will no longer be a need for large dams to be built in Africa. Yet those dams that are being constructed now will in most cases be completed. Let us hope that in the future large dams, including the massive Inga IV dam, will no longer be financed and built.


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David Zarembka

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Reports from Kenya: www.davidzarembka.com

Email: davidzarembka@gmail.com