Stuck in years-long lines for grid connections and new turbines, some AI data centers are making their own electricity with converted jet engines, the New York Times reported Tuesday.

The engines, pulled from retired aircraft and rebuilt to burn natural gas, aren’t anyone’s idea of a permanent power plant. But they’re another sign of how far power supply has fallen behind the AI buildout.

For companies stuck in those lines, the main draw of converted jet engines is how quickly the engines can be up and running. “It’s all about getting power as fast as possible,” Rystad Energy analyst Audun Martinsen told the Times. With jet-powered units, “they can have a data center running in 24 months,” he said.

Hooking up 100 megawatts to the grid in Northern Virginia, by comparison, takes about seven years, according to the International Energy Agency. Most power capacity is expected to come on by 2031, an executive at Mitsubishi Power, one of the world’s top makers of power generation equipment, told Bloomberg last week.

In some cases, these delays are already costing some data center operators business. Last month, Microsoft pulled out as the anchor customer for Nscale’s data center in Loughton, England, after the local utility said it couldn’t deliver enough power until the early to mid-2030s.