Tesla is opening up Powerwall home battery sales, nearly two years after limiting them because its supply was “too low.”

Tesla announced its backup battery tech long ago, in 2015, explicitly intending for the product to work in tandem with solar panels. Yet up until 2021, the automaker also allowed folks to buy the big batteries separately. Eventually, Elon Musk clarified that supply issues were to blame for the restrictions, and the executive teased in 2022 that “ordering a Powerwall by itself should be possible” by the end of the year.

Some months apparently behind schedule, this is now happening — with caveats.

Tesla said this week that it’s now selling Powerwalls separately “in select US markets.” The company hasn’t put out an official list of these markets (as far as we can tell), but Tesla’s website offers a way for prospective shoppers to check if they live in an approved spot.

For example: I typed in my Los Angeles address, and Tesla’s site responded: “We’re assessing where to service next. Reserve your Powerwall to help us expand into your area.” However, the standalone device is available in other areas, such as Austin, Texas.

Tesla relocated to Austin in 2021. A year later, it launched an invite-only electric plan in parts of the state where retail choice is available, including Houston and Dallas. As we wrote in December, the plan is called Tesla Electric and it’s exclusively available to Powerwall users.

Tesla recently told investors that it intends to expand its electric plan to other markets, but the company hasn’t said where it will go next.

You might wonder, “Why would someone buy a Powerwall without solar panels? The stand-alone device could appeal to folks who aren’t in an ideal spot for sun, or for those who don’t want to pay for solar and a home battery all at once. As we observed at CES 2023, lots of companies seem to believe that demand for backup batteries and generators is on the rise — and surely extreme weather events linked to climate change could be driving interest.