What the gigawatt gap is

What follows is what the bodies that measure, and one company's own release, report. Each figure stands with the body that gives it and what it counts, and this page does not choose between them.

How much power data centers use

For the United States, Lawrence Berkeley National Laboratory wrote a report for the Department of Energy in December 2024, designed, it says, to meet a "Congressional request." It estimates that U.S. data centers used 176 TWh of electricity in 2023, 4.4% of all the electricity the country used. That figure comes from what the report calls a "bottom-up" energy use model, which calculates total electricity use from an installed base of data center equipment. The report also says that "the lack of data availability significantly limits the analysis in this report."

For 2028 the report gives a range, not a number. Its scenarios vary the number of GPUs shipped each year, how much and how often AI hardware in the installed base is used, and the type and efficiency of cooling systems, and they run from roughly 325 TWh to 580 TWh, or 6.7% to 12.0% of the electricity the country is forecast to use that year. Assuming an average capacity utilization rate of 50%, the report says that range of scenarios would translate to a total power demand for data centers of between 74 GW and 132 GW.

Ireland's figure is metered. Its Central Statistics Office reports that metered electricity consumption by data centers rose to 7,663 GWh in 2025, up 10% in a single year. Their share of all the metered electricity consumed in Ireland rose to 23% in 2025, from 5% in 2015.

Australia's market operator, AEMO, says that in 2025-26 data centers across the National Electricity Market "are estimated to consume around 5 TWh," 2.8% of operational consumption on that market. Under its Step Change scenario, their consumption is forecast to reach around 15 TWh by 2029-30. By 2035-36 the same scenario forecasts around 34 TWh, "before growth starts to taper off." A note under AEMO's own chart adds: "Since this forecast was finalised, AEMO is aware of greater interest in Queensland than is represented in these 2026 ESOO forecasts."

Connection queues

Another kind of figure counts what is in a connection queue. The Electric Reliability Council of Texas, ERCOT, says that as of mid-2026, large users totaling more than 438,000 MW of proposed demand had entered its connection queue, and that nearly 90% of those requests were from data centers. "To put that in perspective," it adds, its all-time peak demand record is 85,508 MW, set on August 10, 2023. Further on, it says that "ERCOT understands that not all connection requests result in built projects."

In Great Britain, the energy regulator Ofgem reports that contracted demand in the connection queue increased from 41 GW in November 2024 to 125 GW in June 2025, and that around 73 GW of it is data centers, across approximately 315 projects. "For a sense of scale," it adds, peak demand in Great Britain in 2025 was 45 GW.

Its consultation of July 2026 sets out proposed reforms, and the part it calls Curate "focuses on reducing speculative, non-viable projects in the queue and ensuring viable projects are able to progress as quickly as possible to connection." Projects in the queue that are "speculative, non-viable and unlikely ever to connect," it says, "create material harm to consumers."

In Australia, AEMO reports that the total proposed connection capacity of data center projects on the National Electricity Market, across all development stages, increased from 38 GW to 67 GW in its 2026 assessment. Approximately 36% of the known projects on its 2025 list have since been canceled. Its data center forecasts, it says, applied "probability weightings to project pipelines to reflect the estimated likelihood of projects progressing to connection and operation."

Connections and machines

Lawrence Berkeley National Laboratory also reports on the power plants and storage seeking transmission interconnection in the United States. Roughly 2,061 GW was actively seeking interconnection at the end of 2025: 1,312 GW of generation and 749 GW of storage. The report sets that beside the total installed capacity of the U.S. power plant fleet, 1,374 GW, and says on the same page that "This is not an assessment of resource adequacy," that comparisons of queue capacity to installed capacity or peak load "should also consider generators' contributions to resource adequacy," and that "It is highly unlikely that all of this capacity will be built."

About 13% of the capacity that requested interconnection from 2000 to 2020 had reached commercial operations by the end of 2025, the report says. The median project built in 2025 took 61 months from the interconnection request to commercial operations, against 36 months in 2015 and 22 months in 2008. These trends, it says, "raise concerns for meeting growing electricity demand and meeting resource adequacy requirements." Its note on that median says a valid in-service date was available for only 73% of all operational projects.

ERCOT's explainer says its staff found that the historical method of studying connection requests one at a time needed to change. The addition of each new large project, it says, "affected and could potentially invalidate studies for projects that were farther along in the connection process," and the problem "triggered costly restudies that delayed completion timelines." Its staff began working on "a system-wide batch process that studies all eligible applicants together."

Then there are the machines. GE Vernova, which makes gas turbines, reports that its Gas Power equipment backlog and slot reservation agreements grew to 116 GW in the second quarter of 2026. In the same quarter, it says, its gas equipment backlog grew to 53 GW and its slot reservation agreements to 63 GW. Its chief executive, quoted in the release, says the company now expects "to have at least 125 GW of gas equipment under contract by year-end 2026," and that "To meet this demand" it remains on track to deliver 20 GW of annual gas turbine output in the third quarter of 2026, with 24 GW in 2028, both of them the company's plans for its output.

The release gives no share of these gas figures for data centers. It names data center orders in a sentence on "continued demand growth in Electrification, with data center orders reaching over $5 billion year-to-date." Its release says that its forward-looking statements are "inherently uncertain."

Some of the figures, with their kinds

Here are some of the figures above again, each with its kind.

• Measured at the meter. Ireland's Central Statistics Office: data centers' share of metered electricity consumption in 2025, 23%.
• Estimated from a model of installed equipment. Lawrence Berkeley National Laboratory: U.S. data center electricity use in 2023, 176 TWh.
• Forecast. Lawrence Berkeley National Laboratory: U.S. data center electricity use in 2028, roughly 325 TWh to 580 TWh, a range of scenarios.
• Demand in a connection queue. ERCOT: proposed demand of large users in its queue in Texas, mid-2026, more than 438,000 MW.
• Demand in a connection queue. Ofgem: data centers in contracted demand in Great Britain's queue, June 2025, around 73 GW.
• Proposed projects. AEMO: proposed connection capacity of data center projects on the National Electricity Market in its 2026 assessment, 67 GW.
• Power plants and storage in connection queues. Lawrence Berkeley National Laboratory: capacity actively seeking interconnection in the United States at the end of 2025, roughly 2,061 GW.
• The company's own count. GE Vernova: its Gas Power equipment backlog and slot reservation agreements in the second quarter of 2026, 116 GW.

How much of each queue will be built, and by when?