Applying the Water-Energy Nexus for Water Supply—A Diagnostic Review on Energy Use for Water Provision in Africa

Pauline Macharia,Nzula Kitaka,Norbert Kreuzinger

doi:10.3390/w12092560

Abstract

This work explores the application of the Water-Energy Nexus concept for water supply in the African context, where its operationalization is quite limited compared to developed regions. Furthermore, water supply and demand drivers and their influence on energy use are examined. This study found that there is limited literature available on the operationalization of the concept, and energy use is not considered a key performance indicator by water regulators and utilities. Regionally, most of the studies were carried out in the northern and southern Africa, where energy demand for water supply through desalination is high. An analysis of water supply and demand drivers show diminishing quantities of available freshwater, and increased anthropogenic pollutant loads in some areas are projected. Consequently, utilities will likely consider alternative energy-intensive water supply options. Increased population growth with the highest global urban growth rate is projected, with about 60% of the total population in Africa as urban dwellers by 2050. This implies huge growth in water demand that calls for investment in technology, infrastructure, and improved understanding of energy use and optimization, as the largest controllable input within utilities boundaries. However, it requires a data-driven understanding of the operational drivers for water supply and incorporation of energy assessment metrics to inform water-energy policies and to exploit the nexus opportunities.

Highlights

Water and energy resources are intricately connected in their production and consumption [1,2,3].On a global scale, water and energy are placed as Goals Six (6) and Seven (7) in the 2015 launchedUnited Nations Sustainable Development Goals (SDGs), with targets 6.1 and 7.1 emphasizing increased universal access to water and energy, respectively, while 6.4 and 7.3 focus on improving water efficiency and energy efficiency [4]
Compilations of best practices for energy use in municipal supply are available at least for Kenya, South Africa, and Zambia; energy use for the drinking water supply itself is not considered among the key performance indicators for water utilities
There are still very few studies on the application of the concept in the region and energy data is quite difficult to obtain through open calls, given that many water services regulators do not consider energy use as a key performance indicator

Summary

Introduction

Water and energy resources are intricately connected in their production and consumption [1,2,3].On a global scale, water and energy are placed as Goals Six (6) and Seven (7) in the 2015 launchedUnited Nations Sustainable Development Goals (SDGs), with targets 6.1 and 7.1 emphasizing increased universal access to water and energy, respectively, while 6.4 and 7.3 focus on improving water efficiency and energy efficiency [4]. Global efforts to address the role of water and energy resources in a coordinated manner through research and policy for sustainable development have increased steadily with the application of the Water-Energy Nexus framework [5,6]. This close intrinsic interconnection between production, consumption, and management of water and energy resources commonly referred to as the Water-Energy Nexus was discussed in the Bonn 2011. This is to enhance the understanding of the role of energy in water supply and energy saving potentials through technical assessments [10,11] and synergistic water and energy policy formulation [5,12]

Results

Discussion

Conclusion