Span raises $90M to make smart panels the gateway to home electrification

Tesla alum’s startup sets sights on expanding markets for orchestrating solar, batteries, EVs and electric appliances.

Span smart electrical panel mounted on the wall of a home
Span plans to use $90 million in VC funding to expand beyond smart electrical panels to new devices and services, CEO Arch Rao says. (Span)
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The future of home energy lies in getting solar panels, backup batteries, electric vehicle chargers and all-electric heaters and appliances working together smoothly to balance the grid. 

San Francisco–based startup Span wants to provide the master control platform to make that happen, starting with its smart electrical panels. 

On Tuesday, Span closed a $90 million Series B fundraising round to fuel that business plan. The new round, which brings Span’s total funding to $134 million, was led by Fifth Wall and Wellington Management, and joined by Angeleno Group, Robert Downey Jr.’s FootPrint Coalition, Van Jones’ Obsidian Investment Partners, A/O PropTech and previous board investors. 

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In a Tuesday interview, Span CEO Arch Rao, the former head of products at Tesla, highlighted Span’s plan to expand beyond its core product of digitally controllable electrical panels that allow homeowners to track and control power flows between individual electrical circuits. This kind of whole-home balancing is becoming an increasingly important tool to facilitate the installation of solar, batteries, EVs and electric appliances in homes and maximize their value. 

The first such expansion came last year in the form of Span’s EV charger, which it rolled out in partnership with leading U.S. residential solar installer Sunrun. That charger is designed to operate as an integral part of a home’s electricity system, from scheduling charging when grid power is less costly to curtailing other household appliances to allow fast charging when needed. 

In the coming months, Span will be announcing new products and partnerships, as well as enabling more sophisticated interactions between its circuit-level monitoring and control systems and the devices that make up electric-powered homes, according to Rao. 

Over the last two to three years, we were at the tip of the spear, advancing a fairly new technology infrastructure against incumbents that hadn’t innovated much,” Rao said. Now we’ve demonstrated value to homeowners, as well as our channel partners like the Sunruns of the world.” 

The business case for smart electrical panels

Span began shipping its first smart electrical panels in the summer of 2020 and now has installations in homes in 36 states and Puerto Rico. While Rao wouldn’t disclose how many smart panels the company has sold, he said the volume has grown by an order of magnitude” over the past 12 months. 

Span’s first devices cost about $5,000, and its latest scaled-down model costs about $3,500. That’s quite a bit more than the traditional analog circuit panels that are installed in every grid-connected home and building.

But the expanded functionality of Span’s panel can eliminate the need for several additional pieces of equipment commonly needed in homes that are adding solar panels, batteries or EV chargers, such as automated transfer switches and isolation transformers. 

Span’s ability to monitor and manage individual circuits via smartphone app also gives homeowners much more insight into and control over how their homes are using energy, something that vendors of solar systems, batteries, EV chargers and smart appliances are eager to promote. 

This same circuit-by-circuit control also obviates the need to hard-wire dedicated loads for homes that want to conserve and manage battery backup power during blackouts, which is a major reason why a growing number of homeowners are adding batteries to their rooftop solar systems in outage-prone markets such as California. 

These features have helped Span secure partnerships with regional solar installers including Hawaii’s RevoluSun, Texas-based Good Faith Energy and New York–based SUNation — not to mention its Sunrun partnership — and with battery manufacturers including LG Chem, Tesla and SolarEdge, Rao said. 

Span has also been expanding its work with electrical contractors, which is a key piece of electrification at scale,” he added. The U.S. has more than 70,000 electrical contracting firms, with widely varying levels of experience and training on installing solar, batteries, EV chargers, and electric heating and cooking. Helping familiarize contractors with these new technologies is an important step to solve for installations at high volumes,” he said. 

An expanding market for building electrification 

Rao highlighted another feature of Span’s technology that’s just beginning to be explored by homeowners, electrical contractors and utilities: its ability to configure household energy loads in ways that avoid overwhelming the capacity of a home’s existing wiring and power grid connections. 

This will help avoid expensive and time-consuming panel and utility service upgrades, which are a major barrier to rapidly replacing fossil fuel–fired furnaces, boilers, stoves and clothes dryers with all-electric models. Electrifying these appliances is a vital step in cutting carbon emissions quickly enough to mitigate the worst impacts of climate change, according to multiple studies.

We can enable homes [to increase electricity usage] without upgrading the service because we’re managing loads at the service point,” Rao said. Span has partnerships with Vermont utility Green Mountain Power and California community choice aggregator Silicon Valley Clean Energy to test how its panels can be used to avoid utility service upgrades, and it has several more pilots underway with utilities it hasn’t yet disclosed, he said. 

Another pathway to market lies in embedding Span technology in new buildings, Rao added. New investor Fifth Wall, which is backed by some of the country’s largest homebuilding companies, offers Span a path to electrify new homes — multifamily as well as single-family,” he said. 

As cars go electric, and heating and cooking move away from natural gas, we anticipate the amount of electricity flowing through homes will quadruple. This means that several billion breaker panels will need to be upgraded over the next 20 years,” Greg Smithies, partner and co-lead of climatetech at Fifth Wall, said in a Tuesday email. That’s a massive opportunity for Span.” 

Apartments, condominiums and other multifamily housing units have been a particularly challenging market for solar, batteries, EV chargers and broader electrification efforts. Span is working on engineering our products for modularity” to meet the needs of those properties, Rao said, though he wouldn’t provide more details. 

Span isn’t the only company using digital tech to modernize home electrical systems. Schneider Electric, a global residential and commercial electrical equipment provider, launched its Square D Energy Center last year, and rival Eaton makes smart circuit breakers that can be embedded in existing electrical panels. Startups such as Lumin and Koben make digital panels and subpanels that offer similar functionality. 

Rao acknowledged that there will be different products that coexist” in the growing market for helping buildings electrify. That’s why Span is developing software that can allow the company’s platform to communicate with downstream appliances” within homes, he said. 

We’re just scratching the surface of what’s possible here,” Rao said. We want to be the product and technology leader for home electrification for some time to come.” 

Jeff St. John is director of news and special projects at Canary Media.