Updated: Jun 13, 2022
A Span Smart Panel is designed to integrate home energy upgrades like storage, solar panels, and electric vehicle charging. If you're planning to install home batteries, having a Span panel will help you size your storage system correctly.
Arch Rao, former head of engineering at Tesla Energy, is the CEO of a company called Span, which he founded in 2018. His company produces one product: a smart electrical panel that brings intelligence to the power generation and consumption of your entire home.
Electrical panels haven’t changed fundamentally since the 1960s, when circuit breakers began replacing fuses. They are “dumb” tech because they are really designed purely for safety. If a circuit is overloaded, it’s the breaker’s job to shut it down. But there’s a ton of information in the power flowing back and forth through those wires, and Span gives consumers the ability to capture—and control—all of it.
As you might expect, upgrading your home’s electrical panel is not exactly a DIY affair. A certified installer from the Solar Revolution can typically upgrade your current electrical box in approximately one day.
Inside the panel the usual columns of plastic breaker switches fill the space, and each circuit can still be turned on or off manually. The real intelligence is in the Span mobile app.
The primary screen within the app shows where power is coming from (solar, battery, or grid), and where it’s going (to the home, back to the battery, or back to the grid), all in real time. From there, it’s easy to drill down and get insights into (almost) every circuit, detailing each circuit’s current power draw and, over time, how much power each circuit is eating up.
But information like this is only the start. Span is also designed to give you an incredible amount of control over how your battery is used, letting you categorize each circuit among three priority levels:
Must have, Nice to have, and Not essential.
If the power goes out, the Not essential circuits go dark, the Nice to haves run until the battery hits 50 percent capacity, and the Must haves stay on until the battery’s dead.
If you are considering a solar-battery combo for your home, you’ll probably find Span surprisingly hard to live without.