Growth spurt of data centres could threaten SA’s electricity and water supply

There are roughly 12,000 data centres scattered around the world, quietly hoovering up huge volumes of electricity, water and mineral resources.

These data centres are the engine rooms of the global IT revolution — cavernous warehouses that house powerful computer servers and networking equipment that store and process the digital data torrent flowing through a multitude of banks, company offices, websites, email and social media platforms.

So far, they only consume around 1.5% of electricity at a global level. But the demand is growing rapidly across the world — an issue that has special relevance for a country still in recovery mode from the social and economic nightmare of load shedding (as well as frequent municipal water supply failures in Johannesburg, Durban and other areas).

In a recent report titled Energy and AI, the International Energy Agency (IEA) forecasts that data centres are likely to consume more than 4.4% of global electricity supply within the next decade.

That may not sound like a big deal — but viewing global-scale statistics in isolation dilutes the true impacts at a country, city or local dorpie level.

Look at Ireland, for example, where data centres already suck up 21% of that country’s metered electricity supplies (a five-fold increase over just eight years).

There are also six states in the US where data centres use more than 10% of the electricity supply, with Virginia leading at 25%. In Singapore, more than 7% of national electricity supplies are consumed by data centres.

One of the main reasons for this rapid increase in data centre power and water consumption is the global deployment of AI, which includes applications such as ChatGPT. The IEA says AI-focused data centres are getting much bigger to accommodate increasingly larger models and the growing public demand for AI services.

Whereas the power drawn from a conventional data centre may be around 10-25 megawatts (MW), the larger AI-focused data centres can draw 100MW or more. One example is The Citadel, a hyperscale facility in Nevada, US, that has been designed to draw up to 650MW of power — equivalent to more than 40% of Durban’s current electricity demand.

An even bigger 2,000MW centre (aptly named Colossus) is under construction in Memphis, Tennessee, by Elon Musk’s xAI group.

The IEA notes that large data centres can consume as much electricity as 100,000 households.

“The largest currently under construction could consume as much as two million households,” says the IEA.

Little surprise then that some very senior power utility executives in the US and elsewhere are worried about meeting surging demand.

In December 2025, Exelon Corporation chief executive Calvin Butler warned that the US energy system warning lights were flashing and could no longer be ignored.

“It’s like you’re driving your car, the ‘check engine’ light is on, and you just don’t want to take it into the shop,” he told Fortune magazine. “I’m telling you on that hottest day or that coldest day, you might have a supply crunch, and people are going to suffer. I’m telling you, you have to fix it now.”

Currently, the largest data centres are in the US, Europe and China, but demand is also rising fast in the developing world. India’s total installed data centre capacity has doubled in only four years, now consuming electricity volumes equivalent to 6.5 million Indian households.

What about South Africa?

Though power consumption from South African-based data centres appears to be relatively low in comparison to the developed world, Eskom and several municipalities have refused to provide Daily Maverick with electricity consumption statistics by local data centres, asserting that the disclosure of such information is prohibited in terms of the Protection of Personal Information Act or that statistics are not available.

Nevertheless, five Teraco data centres in Johannesburg alone have a combined IT power load of more than 130MW (greater than the municipal power demand of a small city such as Mbombela or Kimberley).

Similar concerns about a potential South African resource crunch were raised in a recent opinion piece published by the National Science and Technology Forum. In the opinion piece, Legal Resources Centre attorney and candidate attorney Aaron Tifflin notes that the latest digital revolution may come with hidden costs.

“All the personal data we generate — every click, message and photo — is stored not in some abstract cloud, but in physical facilities. Despite its fluffy-sounding name, the cloud is not floating somewhere in the sky. It refers to a network of remote servers and infrastructure, maintained by tech giants, that allows data to be accessed over the internet.

“These cloud services are underpinned by physical data centres, which are massive facilities that house the servers, chips and networking equipment required to store and process digital information.”

And as data centres expand, the electrical demand and other environmental trade-offs remain ill-explored, says Tifflin.

“As the country positions itself as a player in the global AI economy, we must ask: at what cost? Technological advancement must go hand-in-hand with transparency, accountability, and responsible stewardship of our natural resources.” DM

As we will see in the Part 2 of this series, local data centres are poised for another major growth spurt.