Tesla Powerwall: What you need to know (Updated)

Tesla Powerwall: What you need to know

Tesla’s Powerwall—a rechargeable Lithium Ion energy storage device intended for residential energy storage—was first announced in 2015. Only one year later, in 2016, an upgrade known as the Tesla Powerwall 2 was announced. Tesla has installed over 200,000 Powerwall units worldwide including sending hundreds of battery packs to Puerto Rico during the extended power outage caused by Hurricane Maria in 2017.


Above: Two Tesla Powerwalls and an HPWC (Image: Teslarati via Dennis Pascual)

The Powerwall has an energy capacity of 13.5kWh with a peak power output of 7kW with continuous output of 5kW. Wall mounted, the Powerwall unit is 45.3” H x 29.6” W x 5.75” D (115cm x 75.3cm x 14.7cm) and weights 251 lbs (114kg). The Powerwall has a sleek, polished surface and simple, geometric design that fits into the design of any building.

From an environmental standpoint, the Powerwall is a stationary power supply designed to reduce your carbon footprint and your reliance on the grid. By using a rooftop solar panel, the Powerwall stores solar energy for all-day use, whether the sun is shining or not. This sleek piece of technology can turn any building into a personalized power plant.



Above: The Tesla Store in Boca Raton, FL hosted a fantastic Powerwall event this past weekend and had all-new Tesla Energy graphics and a demo unit mounted on one of the store's walls (Images: Author)

When the Tesla Powerwall 2 was first announced, Business Insider released an article explaining how the rechargeable battery works:

“Panasonic makes the cells for the Powerwall, while Tesla builds the battery module and pack... [and] the Powerwall can store electricity generated by solar panels and draw electricity from the utility grid when rates are low to store for later use. It also provides homeowners with backup power in the event of an outage. All Powerwall installations must done by a trained electrician."

The article also mentions that the Powerwall is modular, which means it’s flexible. You can install up to nine batteries side-by-side to store more power.

Although Powerwall can be used in homes that do not have solar arrays for energy input, the greatest cost savings are achieved when Powerwall is used with solar. Powerwall return-on-investment (ROI) is calculated by dividing the cost of the Powerwall plus installation by yearly savings. Yearly savings are calculated by subtracting the costs to charge Powerwall (differs depending on whether the Powerwall is charged from the grid or from Solar) from peak utility power requirements.



Above: Tesla Powerwall 2.0 can power the house when the sun goes down (or during a power outage) while the energy from solar panels can be stored during the day into the home battery (Images: TeslaSolarCity)


Above: Tesla Powerwall 2.0 (Image: Business Insider*)

Current pricing for Powerwall 2 is $6,500 per unit with installation costs ranging from $2,500 to $4,500 (approximate). With ongoing software updates, Tesla plans to make additional improvements for Powerwall owners. In May, 2021, Tesla released an update to the Powerwall to better integrate it with their Tesla Energy Plan and Virtual Power Plant, plus they are working with electric utility companies so they can take advantage of the Powerwall as well. The first major update to the Powerwall 2, known as the Powerwall +, has a higher power capacity. It went into production in November 2020, and had its first images and specs revealed in April 2021. The updated version of Powerwall is said to provide approximately 14kW peak power with 10kW of continuous power.