Why do we need Energy? Why do we need Water? Why do we need Food? and How these three basic needs are related to the Earth’s Natural Capital Resources. For Africa where its population will peak to reach about 40% of the world population by the end of this century including housing the youngest population on planet Earth, it is IMPERATIVE to know how this wicked “Water-Energy-Food-Natural Resources” Nexus will be managed. With the huge and growing global pressure on Africa’s mineral/natural resources and with the other given needs in mind, how can we define Africa’s Livelihood on the bases of achieving the UN-SDGs?
The new dams in Africa have the potential to meet increased energy (electricity) demands. At the same time, there are strong coupling between climate and the “water, energy and food” in Africa. Also strong links with the global needs for Africa’s natural resources. On the large-scale and long-terms spatio-temporal changes, locations of the planned dams could put the security of electricity supply at risk for large parts of Africa. As the majority of planned dams are located in river basins with upstream and downstream regions that rely on similar patterns of rainfall and hence be vulnerable all together to drought and dry years. Also, subject to other extreme climate and weather threats caused by major changes in rainfall pattern such as uncontrolled flooding. These vulnerabilities could lead to electricity supply being disrupted. This is why it’s important to factor climate variability and change into dam design and management, and diversify the electricity production, to avoid over reliance on hydropower.
Hydropower relies on the flow of water to drive turbines for electricity generation. It uses natural changes in elevation or artificial storage in reservoirs to take advantage of the water level difference. Drought or successive dry years can result in not having enough water to drive the generating turbines and thus cause shortage of electricity. In countries like the US and in parts of western Europe hydropower is complimented by other power sources. This means that in times of drought other sources of power can balance the shortfall. But in countries where the energy mix is or will be dominated by hydropower as in e.g. Africa specially the sub-Saharan African countries. Without alternative power sources, the impacts of climate can cause fluctuations in hydropower and thus can disrupt electricity supply. Supply might need to be turned off either to ration dwindling water resources or because demand simply can’t be met. For example, the Nile and Zambezi, where multiple dams are planned on the same river channels and lie in the same rainfall clusters. This means that dry years will affect storage in all the dams, lessen their ability to refill fully and could create a significant challenge for the supply of hydropower. There are already examples of this happening (http://theconversation.com/new-dams-in-africa-could-add-risk-to-power-supplies-down-the-line-89789). In December 2017, for example, Malawi’s state owned electricity company saw power output plummeting after a severe drought. Malawi relies almost entirely on hydropower and during the 2015–16 El Niño event, Malawi, Tanzania, Zambia and Zimbabwe all experienced electricity outages due in part to reduced rainfall. Climate risks must be built into planning, this is particularly true in many of Africa’s river basins because they are highly sensitive to changes in rainfall. The increasing importance of hydropower and the potential for increasing levels of rainfall variability under climate change, underscore the need to incorporate climate risks into infrastructure planning in Africa.
There is no question the planned increase in hydroelectricity generation in Africa presents both significant opportunities and also challenges. It will assist the economic development of the continent, as greater electrification will drive industrialisation and support the creation of more secondary and tertiary industries. All these come with several socio-economic opportunities. Also, increase in water storage capacity will assist the agro-industry, by reducing its reliance on rainfed agriculture. However, an over reliance on dams could threaten food, water and energy security during times of drought, and would present challenges to a wide-range of communities that rely on the natural flow of water in rivers. Also, the boom of industrial and household activities around centralized power-stations and artificial water reservoirs can cause local and regional degradation in air and water qualities if strict rules and regulations for emissions and/or injections of pollutants are not properly put in place. These emerging threats and challenges need to be assessed with the water-energy-food nexus and life-quality in mind. If African countries seek to harness the wide benefits that their rivers provide, they must also learn from previous mistakes, minimise and mitigate the negative effects of the ongoing dam building.
The number of challenges that Africa presents in terms of energy-water-food nexus and life-quality are significant. As such nexus has also several feedback impacts on eco-system services and bio-diversity. Furthermore, the lack of adequate management of available water resources is contributing to an existing and accelerating water crisis in the African continent. Changes in climatic patterns are also expected to have impacts on crop yields, which in combination with population growth will lead to severe additional stress on water resources that otherwise would have to be dedicated to increase agricultural productivity. Under these scenarios, future water needs from the growing African energy sector may play a key role when combined with changes in water availablity and the future increasing demands from agriculture. A proper analysis of the water requirements of the African energy sector is important for an effective future planning and management of water, energy and food resources in Africa.
This said, an important and interesting issue is the impacts of water needs for energy use and production on the natural water cycle on local and regional scales in Africa, also probably on the global scale because of evaporation from an increasing number of artificial reservoirs behind the planned hydropower dams in the arid and semi-arid regions in Africa.
At this stage we give only one example on the ongoing plans in Ethiopia for hydropower production. However, sustain-earth.com will continue in detailing the what, why and how issues in the “water-energy-food nexus” in Africa. Follow the story here (https://youtu.be/NbKoXlYUNY0).