The once-tiny residential battery market is attracting dozens of new entrants, including recognizable consumer brands like Anker, Duracell and Energizer.
For years, the residential energy storage market was a sleepy place dominated by one big name. Now, more companies are rushing to sell these products than ever before, and some of the new contenders are brands people have actually heard of.
The iconic copper and black Duracell colors now grace a solar-battery product. The perpetually active bunny mascot from Energizer similarly wants to keep your house powered through blackouts with clean energy. Anker, a dominant force in chargers and power packs for personal electronics, has harnessed its engineering and consumer design experience to produce the Solix X-1 solar-battery system, joining a lineup of portable battery packs already on the market.
All this new competition is crucial for turning rooftop solar into a more valuable clean-energy resource. Home solar on its own produces clean energy when the sun shines. Rooftop solar hooked up to batteries empowers households to ride through grid outages unscathed, but it also lets them share clean energy with the grid at hours of peak demand. Networks of home batteries add up to meaningful capacity: They’re already keeping the lights on in Hawaii after a major coal plant retirement and saving Vermonters millions of dollars in grid costs each year.
The Department of Energy wants to supercharge the development of these networks of customer-controlled energy devices, also known as virtual power plants. A “commercial-liftoff” report published by DOE last week details how supersizing these aggregations can reduce the need for fossil-fueled “peaker” plants and save money on grid decarbonization by leveraging stuff people are buying for themselves anyway. But for this decentralized vision to succeed, customers need a ready supply of products that they actually want to buy.
Consumer preference is tricky to predict, but the supply, at least, has arrived. In Las Vegas last week at the 40,000-attendee clean-energy trade show RE+, a stroll around the gargantuan two-story expo hall revealed what could be called a Cambrian explosion of residential battery species, if it weren’t imperative to avoid careless references to explosions when discussing lithium-ion batteries.
“It catches the eye to see how many storage options were being showcased at RE+ this year,” said Spencer Fields, director of insights at online solar and storage marketplace EnergySage.
Too many vendors to count are hawking family-sized battery storage products. The vast majority of those new entrants have little to distinguish themselves at this point — they’re anonymous brands selling equally anonymous boxes that do exactly the same thing. Home-storage vendors haven’t learned the lessons of Las Vegas, which entrances even sharp-minded cleantech analysts with its kaleidoscopic colors and sounds.
Nevertheless, these battery packs now enjoy a decade of lucrative tax credits from the Inflation Reduction Act. Seemingly nonstop climate-driven disasters this year have made backup power more visibly valuable than ever before, and new rules in California, the largest home solar and storage market in the country, made batteries essential to selling rooftop solar. Manufacturers from outside the traditional solar industry have noticed.
Democratization of residential energy storage
Tesla didn’t invent battery storage for homes, but Elon Musk popularized the concept when he launched the first Powerwall in 2015. Tesla then dominated the early years of the fledgling U.S. residential storage market, especially when its second-generation product, unveiled in late 2016, had increased storage capacity and dropped the price relative to competitors. Tesla promised a built-in inverter at the time but has taken a while to get around to it: The company made headlines last week for promising the exact same thing in the forthcoming Powerwall 3.
Mercedes-Benz tried to follow Tesla from automotive batteries into home energy, then quickly gave up. Other early adopters kept plugging away, building their home battery brands for American households: German startup sonnen, Tetris-purveyer Henk Rogers’ Blue Planet Energy, South Korean battery juggernaut LG. But an early market where most customers clamored for a single brand left something to be desired: Whenever Tesla fell behind in shipments, which happened regularly as the company prioritized electric-vehicle production, the delays rippled throughout solar-battery installer networks.
For several years now, though, the home storage market has been steadily diversifying.
EnergySage regularly analyzes consumer preferences based on the solar and storage quotes that installers generate on its comparison platform. When its storage marketplace launched in the summer of 2020, Tesla still led in terms of the number of times its batteries were quoted, followed closely by LG Chem. But at the end of that year, the Korean company recalled some of its home storage systems due to fire concerns, dampening enthusiasm for the product.
Subsequently, leading solar microinverter manufacturer Enphase took market share with its modular battery offering.