Water and energy are interdependent resources; they rely on and inform each other, which necessitates integrated planning, particularly in the face of climate change. For Eskom, South Africa’s largest energy utility, water security is paramount to its energy operations.

Gabi Mkhatshwa, senior manager for climate change and sustainable development for Eskom, notes, “Eskom is a strategic water user, which grants the entity 99.5% assurance of supply. Eskom utilises approximately 3% of South Africa’s freshwater sources, primarily sourced from the Integrated Vaal River System. We use 270 000 000 m3 per annum for our operations. For us, water is as important as coal; without it, we cannot generate electricity.”

Water is a primary resource used in the generation of electricity. Eskom’s coal base load power stations are located inland, and use raw fresh water for:

• Cooling: Cooling the generation units.
• Steam generation: The coal burned evaporates water that turns the steam turbine, generating electricity.
• Ashing: Managing burnt coal requires mixing the ash with water and storing it.
• Washing and,
• Air emission and abatement: Water used to reduce emissions

Mkhatshwa adds, “Wet cooling represents a substantial portion of our water use, and while inland we are reliant on freshwater assurance, at stations like Koeberg, seawater is used, Water quality is crucial for Eskom, and mitigating environmental impacts is just as crucial for us.

Water agreement

Eskom’s long-term water security is assured through various water supply agreements, a bulk water license, and augmentation projects.

• Eskom’s agreement with Rand Water is pivotal, and the existing agreement has been extended to April 2038.
• The Vaal River Eastern Sub-Systems agreement lasts until April 2026, but there are negotiations in place for a new agreement of 11 years.
• The Komati Water Scheme expires in March 2034.
• Eskom’s bulk water abstraction license for the Integrated Vaal River System has been submitted to the Department of Water and Sanitation (DWS) for renewal by June 30th, 2025.
• Eskom’s Mokolo River System bulk water abstraction license was renewed by DWS and expires in 2051.

Water supply assurance and the various licenses do not mean that Eskom can misuse this water; the energy utility has internal mandates that govern water efficiency that predate the current climate-focused resilience.

“In 1989, Eskom used 1.9 litres (ℓ) per kilowatt (kW) sent out; we have improved our water efficiency to 1.47 ℓ per kW sent out, and we have an internal target of 1.38 ℓ per kW sent out. Technological solutions, effective water management policies and procedures have improved our efficiency, specifically dry cooling and ashing systems that do not heavily rely on water,” says Mkhatshwa.

Despite the improvements, Eskom still faces several obstacles regarding its water use. Eskom’s water management strategies and plans are not implemented consistently Mkhatshwa adds, “An example is the Zero Effluent Liquid Discharge plan, while it is in place, we have minimal water reuse and recycling.”

Climate change and energy transition

The impact of emissions from coal power on the environment has led South Africa to pursue a diversification of its energy mix, primarily led through the Just Energy Transition (JET).

“The diversification of the country’s energy mix away from coal primarily will significantly reduce Eskom’s water footprint over the next 10-15 years,” says Mkhatshwa.

Water supply assets are integral to South Africa’s water security, and DWS, Eskom and Sasol have launched a joint task team to manage bulk infrastructure assets to preserve and build the water security needed for continued operation.

Mkhatshwa says, “South Africa must deal with years of poorly managed municipal infrastructure, water losses, and insufficient storage, as this affects us as Eskom and as every South African. Climate change is now an additional worry as the droughts and extreme weather events threaten not only the supply of water but also infrastructure, we need as a country.”

The asymmetric and disproportionate effects of climate change mean that South Africa warms at twice the global average rate. An already water-scarce country, climate change threatens to:

• Decrease the average precipitation
• Increase the frequency and intensity of floods
• Increase heat waves
• Increase and prolong droughts.

Mkhatshwa adds, “As well as these national concerns, there are regional and local climate risks we face. Areas prone to wind will see increases in wind speed, which impact on our infrastructure, and along the eastern coast, there is an aggravated risk of stronger and more frequent tropical storms. This is not to say this going to happen in future, this is happening now, and we are feeling the impacts.”

Climate risk mitigation and strategy

Eskom’s approach to climate change involves three steps:

1. Understand the risks as comprehensively as possible and ensure that the measures put in place are achievable. This is detailed in Eskom’s climate change policy, strategy, and adaptation procedure, which are adopted across the entity.
2. Ensure that these guiding documents are understood by all employees, and how their operational processes are impacted by climate and how the strategy shapes new practices and goals.
3. Review the strategy and procedures by monitoring operations, and how they adapt or fall short. Monitoring and evaluation of implementation is critical in informing progress and necessary adjustments responding to the constantly evolving climate space.

“The hard work is ensuring the data and information we get is credible and valuable. We speak directly to employees, stay on top of trends, look at other case studies, and ensure that the policy we craft is not only adequate but also context-specific and workable. If the challenging work is done at this step, it becomes easier to implement and monitor our solutions,” says Mkhatshwa.

Eskom’s adaptation journey

Initially Eskom’s strategy was informed by mitigating climate change, but as time went on, Eskom adopted a systematic approach incorporating adaptation they realised that they had to shift their focus to dealing with the current reality of climate change instead of some future prospect.

Mkhatshwa adds, “By looking at active risks we could monitor and adapt in shorter time periods, and work towards long-term goals. In 2015, we worked with the Council for Scientific and Industrial Research (CSIR) to properly understand our risks, vulnerabilities, and the actual impacts of climate change on our operations. While we have been looking at this for a while, we are still in the infancy of our climate risk strategies, and there is a lot of work still needed for us to comfortably say we are mature in our resilience.”

Eskom’s progression since 2010 can be broken down as follows:

• 2010-2015: Eskom’s first climate Change adaptation strategy adopted.
• 2015-2018: Research partnership with the CSIR, focusing on modelling climate change projections up until the year 2100. An integrated risks and resilience Management procedure for adaption to climate change planning was developed and communicated.
• 2019: Initiated phased development of the divisional adaptation plans.
• 2020-2023: Additional modelling research on climate extremes was carried out by the CSIR. Related operational risk assessments were initiated and reviewed. Further research on the impact of climate change on catchments and dams is needed.
• 2025 and beyond: Drive the implementation of processes of divisional adaptation plans and adaptation related projects. Monitor and refine the metrics and continually review risks. Continuing research and further academic partnerships.

Mkhatshwa adds, “Eskom’s strategy involves continual updates and improvements. This is also coupled with broad stakeholder engagement and continuous communication of updates and strategies internally. Climate change’s impact can only be mitigated if we work together and ensure that our policies and actions reflect the realities we face.”