Earlier this year, Lyft launched a new feature called “Green Mode”, which allows riders to request an electric or hybrid vehicle for their trip. The company is now partnering with Portland General Electric to offer up free charging for drivers in the Portland, Oregon metro area.

Starting on July 1st, drivers in the Portland area will be eligible to charge their vehicles free of charge at a variety of locations in the area. According to its website, PGE says that it has 3 “Electric Avenue” locations in the city that are currently active, with two additional ones set to open “mid-2019. It also says that it will add two more by 2020. Each “electric avenue contains four chargers — four DC fast chargers and two level two chargers. Drivers can purchase Level 2 charging ($3 for two hours) or DC fast charging ($5 for two hours), or an unlimited membership for $25 a month.

What’s not immediately clear is whether or not Lyft will introduce a similar perk to other cities in which the feature is available — we’ve asked them for comment, and will update if we hear back.

Lyft initially launched Green Mode feature in Seattle, and it said at the time that it’s rolling it out to other cities across the United States over the course of this year. At the time, Lyft didn’t say how it planned to incentivize EV and hybrid drivers to sign up for the service or to switch vehicles, but free charging could certainly be a good perk for drivers.