Drivers of a handful of fuel-cell cars face a mini energy crisis in California. Right now, hydrogen stations around Los Angeles and San Francisco are in short supply of the fuel.

The news comes from Twitter user ‘Paulo NonVTEC Acoba’, who tweeted a photo of a warning to Toyota Mirai drivers. The warning was posted to the hydrogen fuel pump and noted slow hydrogen deliveries across the are and advised owners to top off frequently. Curiously, it also said Toyota is aware of the issue and dealerships will “comp you for a rental car.”

Green Car Reports reported on Friday that Toyota is indeed aware of the issue but the automaker made no mention of free rentals.

“While the station operator works to resolve this short-term issue, we are working with our Mirai (fuel-cell car) customers to help identify alternative fueling options, including as a temporary measure, opening our commercial hydrogen fueling station at the Port of Long Beach,” Toyota said in a statement.

SEE ALSO: Toyota Expands Hydrogen Fuel Cell Production in Japan

According to the report, the supply issue stems from chemical provider Air Products. The company said an “unexpected disruption” at several liquid hydrogen production and supply sites has stalled deliveries.

“We are addressing the matter as rapidly as we can and are hopeful to have the situation remedied and have restored regular hydrogen supply in the early days of August,” an Air Products statement said.

Only a handful of automakers sell fuel-cell powered cars currently: Toyota, Hyundai, and Honda. The group of owners is experiencing first-hand why alternative fuels are just that: an alternative to gasoline for the time being.

[Source: Green Car Reports]