With the upcoming wildfire season in California and Covid-19 stay-at-home requirements, many people are looking into ways to power their home when utility power goes out. Battery backup systems coupled with rooftop solar are an ideal solution to keeping the lights on during these blackouts. Although these battery backup systems are affordable, quiet and clean — there are limits to the amount of power they can provide.
We all have had experiences with the limited energy capacity of batteries — neither our phones nor EVs seem to run as long as we would like. Moreover, we know that battery-powered devices cannot provide as much power (sometimes referred to as in more technical terms as “oomph”) as devices that have cords plugged into the wall. These limitations are based on both the energy capacity in the battery (measured in kwh), as well as the power delivery capacity of the battery (measured in watts).
Large appliances in homes presents the biggest challenge to powering a whole house with battery power. Power requirements for a central AC, electric oven/stove, pool pumps or EV chargers can be over 5,000 watts each. If these appliances were to be powered by a battery backup system with a 10 kwh or 13.5 kwh battery, that battery would be discharged completely within a few hours — leaving no more energy for more essential items such as refrigerators, lighting and computers. Of course, a determined DIY homeowner could turn off the circuit breakers to these appliances when the power goes out. But this approach does not work if the blackout occurs at night or when no one is home.
To solve this problem, Span has developed a “smart” electrical panel that provides detailed control and monitoring over every single electric circuit in your house. Arch Rao, CEO of Span, is our guest on this week’s Energy Show. Prior to founding Span, Arch was head of products at Tesla Energy, working on their PowerWall, and previously he was at the Westly Group and Stanford University. Please join me as Arch explains how Span makes home energy connected and intuitive with a smart electrical panel.