Free parking for electric vehicles at state airports in Hawaii is set to expire at the end of the month, according to state transportation officials.

The Hawaii Department of Transportation is reminding EV owners that the perks, which also include free parking at most state and county parking lots and meters due to the law enacted in 2012 is scheduled to sunset on June 30.

Starting July 1, HDOT says EV owners will be charged a fee for all of the above.

Act 168 offered EV owners special electric vehicle license plates, which gave them numerous perks, including the free parking as well as use of the High Occupancy Vehicle lanes with a single driver, to provide incentives for the purchase of the cars.

The upcoming expiration of perks comes as the number of registered passenger EVs in the state continues to grow, at least according to the monthly energy report from the state Department of Business, Economic Development and Tourism.

According to DBEDT’s May report, the number of passenger EVs in the state grew to 12,140, an increase of 2,856 vehicles, or 30.8%, from the same month last year, and an increase of 152 vehicles, or 1.3%, from April.

The state Highways Division said it is working to continue to offer EV vehicle owners the use of HOV lanes beyond June 30 because the Federal Highway Administration supports it.