Volkswagen built its Arizona Proving Grounds for hot-weather testing of new cars. Now the automaker is subjecting charging stations to the Arizona heat as well.

A 50-space charging site was recently added to the Maricopa, Arizona, facility, VW said in a press release Wednesday. This will allow for charging electric cars in temperatures up to 120 degrees Fahrenheit, the automaker said.

The site includes 25 DC fast-charging stations with variable power outputs ranging from 50 kw to 350 kw, as well as 10 Level 2 AC charging stations.

The stations include plugs from three major markets: United States (CCS1), Europe (CCS2), and China (GB-T). VW also used a mix of charging equipment from different global brands to maximize testing variability. Pads for wireless inductive charging will be added in the future, VW said.

Built at a cost of $9 million, the charging site includes 16 parking spaces with awnings, which can be deployed to simulate parking in the shade. Tests are monitored from an onsite building to protect workers from the Arizona heat, and the site has a battery monitoring system to detect potential overheating.

Charging stations at Volkswagen Arizona Proving Grounds

The site was built in partnership with Electrify America, the VW affiliate created as part of the automaker's diesel-emissions cheating settlement to build charging infrastructure. Work was completed in February 2020, but certification was just completed this month, VW said.

Automakers have conducted some cold-weather charging tests, but hot weather presents a separate set of issues.

Early Nissan Leaf owners found that the car's air-cooled battery was ill-equipped for Arizona temperatures—in the same climate where VW's proving ground is located.