No matter how close the electric takeover of the auto industry seems, there’s always the occasional reminder that the future isn’t as perfect or as within reach as we imagine. Take this -based , which only made it a lap and a half at full power recently before getting too hot.

Despite production Model S cars having a reputation for , that “full power” part is key, and a spokesperson from Electric GT told Jalopnik in an email that several factors contributed to this racing version’s quick return to the pits for some air.

Electric GT is a series for electric production race cars that’s been approved by the FIA, which governs dozens of international racing series including Formula One. The series uses a with , and announced Monday that it wants to expand with more manufacturers and more powerful cars .

Racer and former Top Gear presenter Tiff Needell at Circuit de Barcelona-Catalunya, and said it’s about half a ton lighter than the street version. A spokesperson for Electric GT told Jalopnik that the car Needell was in is the race-going car, not a prototype.

But Needell’s run didn’t last long, because battery overheating sent the car back to the pits after a lap and a half.

Needell noticed a drop in power on the car and pulled it into the pits soon after, saying the heat was “having its effect” just a lap and a half in. Leaf blowers were shoved into the car soon after to bring the temperature down. Needell didn’t say how significant the power drop was while driving, but that he was pulling in since other people had ride alongs scheduled in it after he got out.

A lap at Circuit de Barcelona-Catalunya is just under 2.9 miles, meaning the car probably lasted around 4.5 miles at full power before Needell noticed the power drop. When the series announced its earlier this year, it said rounds would consist of two races, each at just over 37 miles long. (Formula E will in New York City this weekend, with a car swap during each and with this car has.)

While the production Model S is a great track car for about a lap before it , too, the series spokesperson told Jalopnik there was more to it than routine overheating. The spokesperson said this was the first full day of testing at race speeds, and the car had been out all day in the heat before Needell got in.

The engineers also later found sensor issues that let the battery get hotter than it should have, the spokesperson told Jalopnik.

“The team spotted an accidental disconnection of one of the outdoor temperature sensors from the air conditioning system, which caused the air conditioning system to not send cold air to the battery and other systems when needed,” the spokesperson said. “There is always a limit if the power is used indiscriminately, but the resistance threshold is much higher if the air conditioning system had worked correctly. The team has now fixed that.”

The spokesperson also said the technical team confirmed that the car will be able to run the race distances, but at a more manageable pace—around 470 HP will be what the cars can maintain throughout the race, with the full 778 HP available for things like overtaking. The spokesperson said each driver will have “full control” over when they decide to use the car’s full power, and that it’ll be “part of the strategy and part of the show.”

We’ll get to see how that show plays out soon enough, since the for the international series is scheduled to start in November.