Tesla gave some Florida vehicles a range bump so owners could escape Hurricane Irma

Florida highways were gridlocked on Friday as close to 6 million drivers headed north to escape Hurricane Irma.

It was a taxing experience for drivers in traditional gas-powered vehicles who experienced hours-long lines at gas stations. But it was also a stressful experience for electric-car owners who were worried about running out of juice before making the escape.

Tesla was able to assist some customers in the storm's path.

Tesla previously sold Model S and Model X vehicles with a 75-kWh battery pack, but gave owners the option to only purchase 60kWh or 70kWh of energy. That way, owners could buy a cheaper vehicle, but pay for the extra range at a later date. Like all vehicle upgrades, Tesla can push through the range bump via a software update.

One customer asked Tesla for access to the software upgrade so he could evacuate easier, a Tesla spokesperson confirmed to Business Insider. Now all Tesla owners in the hurricane's path can get the update for free until September 16, provided they have the base Model S and Model X.

The update releases an extra 30 to 40 miles of range, Electrek reported. It can cost between $4,500 to $9,000, depending on the vehicle model.

It was a nice gesture from Tesla that also highlights the biggest issue with electric cars. Most vehicles have yet to achieve a range that people are comfortable with, a problem that faces greater scrutiny in emergency situations.

Tesla no longers sells the base Model S and Model X vehicles, so future buyers have to settle on a range they're comfortable with and pay accordingly going forward.

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