Mercedes-Benz maker Daimler is evidently planning for a future where luxury cars refuel in their own garages. The German automaker is announcing a partnership with Vivint Solar, an American solar panel installer, to sell residential solar panels with modular, stationary storage batteries.

The venture is a product of Mercedes-Benz Energy, a new subsidiary created in 2016 to move into the residential energy storage market. The company builds 2.5kWh lithium-ion batteries in Germany, which can be interconnected to create a system as large as 20kWh.

David Bywater, CEO of Vivint Solar, said in a statement that the price of the system would vary. “A fully installed 2.5kWh battery system, when paired with a solar energy system will cost about $5,000,” he said. But a 20kWh system will only cost about $13,000 fully installed. “Some installations may cost more or less depending on customer needs/special requests."

A “fully installed” system includes the battery, an inverter, professional installation, permitting, and a consultation with Vivint Solar to design the system.

Of course, the economics of batteries are complicated and depend highly on the region you live in and your electricity provider. For now, a battery-connected solar system from Mercedes-Benz Energy and Vivint Solar will only be available to US customers in California.

“Once the required permitting is secured by Vivint Solar, the physical installation of the entire system, including the solar panels and the battery, typically takes one to two days,” Bywater's statement noted. The batteries are covered under a 10-year warranty.

Daimler has been testing out battery projects for a few years. It has produced residential batteries in Germany and started an interesting project in late 2015 reusing old electric car batteries for grid-tied storage. In addition to electric cars, Mercedes-Benz has announced plans for an electric heavy-duty truck as well as wireless charging technology.

The move also comes just a week after Tesla announced pricing on its own solar roof—a system that uses solar tiles to produce electricity. Tesla’s Powerwall battery, which can be integrated with the solar roof, was one of the first residential energy storage products on the market in the US. Companies like Sonnen were installing residential batteries outside the US before that, but Tesla's move prompted the company to sell batteries stateside.

Correction: Spokesperson Mandi West relayed a statement from CEO David Bywater to Ars, so quotes have been updated to be attributed to him.

Listing image by Mercedes-Benz/Vivint