Rising data center electricity use risks blackouts during winter storms

The explosive growth of data centers could threaten the stability of the electrical grid this winter, according to an industry overseer.

Across North America, demand for electricity this winter is expected to be 2.5% higher than last year for a total of 20 gigawatts, the North American Electric Reliability Corporation (NERC) said in a report released this week. In recent years, winter demand grew by 1% or less. 

Data centers are driving a significant chunk of that growth, especially in the mid-Atlantic, U.S. West, and U.S. Southeast, “areas where a lot of data center development is occurring,” Mark Olson, NERC manager of reliability assessments, told E&E News.

The report specifically calls out data center expansion in Texas, saying that it is “contributing to continued risk of supply shortfalls.” That stat might be particularly worrisome to Texans, who nearly five years ago suffered through massive power outages during an intense cold snap. 

At the time, natural gas power plants tripped offline as wellheads froze, slashing the supply of natural gas. Meanwhile, demand for the fossil fuel soared as residential and commercial customers tried to keep homes and offices warm. (The governor publicly blamed wind turbines, despite knowing that they were only a small part of the problem.)

This year, NERC said the situation in Texas isn’t likely to be as dire as it was in February 2021, in part because so many batteries have been added to the state’s grid. Those batteries can step in to provide electricity if gas-fired power plants can’t deliver as intended. Plus, they can react more quickly to smaller perturbations than so-called “peaker” power plants, most of which run on natural gas and require minutes to spin up.

Still, Texas isn’t entirely in the clear. 

Most of the batteries deployed in Texas can deliver electricity for a few hours at a time. That’s suitable in circumstances where demand tends to peak for a short time, like in the evening when people return from work. 

But as NERC notes, data centers tend draw electricity consistently throughout the day. If a prolonged cold snap hits the state, keeping those batteries sufficiently charged to deliver power to all customers — data centers included — will become more challenging, NERC said. 

If this winter passes without a significant storm, then NERC anticipates no problems with any region’s electrical grid. But over the last five years, there have been four severe storms, the organization said, which could force grid operators to import electricity, ask large customers to curtail their use, or as a last resort institute rolling blackouts.