Energy
UK energy storage startup takes on Tesla Powerwall 2 in home battery market
Tesla, Inc.’s CEO Elon Musk has made his company’s mission to help the world to transition away from reliance on fossil fuels and toward the embrace of sustainable energy sources. Now a U.K. energy-storage startup called Powervault is now in competition with Tesla, Inc. to outfit homes with affordable backup battery power across the pond.
Why is solar power and storage the key to the world’s energy independence?
Solar photovoltaic (PV) power generation is at the heart of a transformation that will revolutionize the world’s electricity systems, letting consumers produce power for their own needs and feed surplus energy into the grid. Solar power is becoming ubiquitous: from large-scale utilities to micro-grids; from billion-dollar corporate HQs to rural rooftops; and from urban sprawl areas to small islands and isolated communities. We see solar next to airports, along highways, in fields, powering road signs, even at local small businesses like breweries.
- Brewing company integrates Tesla Powerpack and solar with beer-making
- North Carolina creates state’s first microgrid laboratory, using Tesla Powerpacks
Energy storage is an essential link needed to make intermittent solar energy reliable. Batteries installed inside homes can store excess energy produced by panels during peak hours of operation. When combined with smart meters and digital technologies, batteries can help utilities regulate the grid by providing power reserves which can be tapped and transmitted on demand.
As prices have dropped, solar PV generation uptake by households and local communities has increased dramatically. In 2015, around 30% of solar PV capacity installed worldwide involved systems of of less than 100 kW. This is gradually changing the face of power system ownership. Two companies — U.K.’s Powervault and the U.S. Tesla — are helping consumers to make the shift to solar installations combined with battery energy storage and a chance at energy independence.
Powervault
Founded in 2012 with money from the U.K. government and private investors, Powervault has made a mission of reducing the cost of batteries in order to make them affordable to more homes. Powervault stores electricity in a home using either Lithium-ion Phosphate cells or Lead Acid batteries.
Powervault’s Lead Acid version is for customers who want a product with a low up-front cost and the prospect of upgrading to Lithium-ion technology when their Lead Acid batteries reach the end of their useful life in three to seven years. With Lithium-ion technology forecast to fall dramatically in cost over the next five years, customers can benefit from a low-cost Powervault using Lead Acid batteries now, then replace its batteries later. A Powervault lead battery that can store 3 kWh of power sells for 2,500 pounds ($3,117) a unit, or, about $1,039 for each kWh of electricity stored. That price is about 12 percent cheaper than the $1,175/kWh average price in the industry, according to Bloomberg New Energy Finance.
Photo: Powervault
Powervault’s Lithium-ion Phosphate cells can store 2kWh – 6kWh of usable (AC) energy. Powervault’s Lithium-ion version is for customers who want a product with battery technology that is long-lasting and efficient; the Lithium-ion Phosphate cells are estimated to have a lifetime of eleven to thirteen years and can cycle more than once per day.
Depending on the battery technology and storage capacity a homeowner requires, the dimensions of the Powervault unit vary. The standard G200 unit accommodates all available battery capacities and technologies; the slim-line, G200-S unit , available starting in March, 2017 will only accommodate 2kWh or 4kWh of Lithium-ion Phosphate cells.
The company anticipates prices for Powervault’s batteries, which can cover about half an average British home’s daily power consumption, will be even cheaper going forward. Powervault is planning to expand internationally in the next few years with an initial focus on Europe, according to Powervault’s Managing Director Joe Warren, who said some units have already been sold in Spain. “We’ve been very careful to design them to be universally compatible. We want them to be easy to install and use everywhere in the world.”
Tesla Powerwall 2
Powerwall 2 stories are becoming commonplace, in which a consumer captures energy during daylight off-peak hours with SolarCity photovoltaic solar panels stored in a Powerwall home battery unit. When energy rates are higher during evening hours, the consumer powers the home with energy stored captured earlier in the day.
Artists rendition of a Red Founders Series Tesla Powerwall 2.0 hand signed by Elon Musk
Powerwall uses an internal inverter to convert DC energy to the AC energy required for a home or small business. A liquid thermal control system regulates Powerwall’s internal temperature to maximize battery performance in any climate. The most affordable home battery in terms of cost per kWh, the company argues that the Powerwall economically meets the daily energy needs of most homes. With usable capacity of 13.5 kWh, the Powerwall system has a 100% depth of discharge and 7kW peak / 5kW continuous power. Floor or wall mounted, indoor or outdoor, the Powerwall has a ten year warranty and is scalable up to nine Powerwalls. Its operating temperature ranges from -4° to 122°F / -20°C to 50°C. The system is certified to meet North American and international standards.
One 14 kWh Powerwall battery costs $5,500, with installation and supporting hardware adding $1,500, or a total estimate $7,000. U.S. installations are beginning in February, 2017, according to company data.
There’s no doubt Elon Musk sees solar as the future for electricity generation, just as he views electric cars as the future of transportation. “The primary means of energy generation is going to solar,” he said in 2015 prior to the merger with SolarCity, in which the issue of utility-based versus independent energy generation still seemed futuristic. “It will at least be a plurality, and probably be a slight majority in the long term.”
The forecast for solar in the U.K. and U.S.
The London-based Powervault company is targeting sales of 50,000 units a year by 2020, up from about 1,000 this year. Powervault is entering the home storage market just as Tesla is readying its Nevada-based Gigafactory for Model 3 production. Musk expects the plant will double the global production of lithium-ion batteries next year, so that, by 2018, the Gigafactory will reach full capacity and produce more lithium ion batteries annually than were produced worldwide in 2013.
Solar PV deployment at the consumer level alongside battery storage is putting pressure on network operators and the way national electricity systems are traditionally managed and governed. This is brought about by new developments in electricity storage, electric, vehicles and smart appliances. Solar PV already accounts for about 2% of global electricity in 2016, but could reach as much as 13% by 2030. In order for this to happen, solar PV capacity additions must double in 14 years, with Tesla leading the way and companies like Powervault joining the march.
Interested in solar? Get a solar cost estimate and find out how much a solar system would cost for your home or business.
Tesla has started to perform earthworks engineering on the roughly 3,000-acre site in Fort Bend County, Texas, advancing the massive $10 billion Project Crystal Sun plan to build a vertically integrated solar manufacturing complex.
Flyover drone footage from S.E. Robinson, Jr. released this morning shows the location under development. Tesla has crews on site performing large clearings, but you can also see equipment staging areas, the use of an existing homestead, and active leveling across a substantial portion of the property.
Tesla has started construction on Project Crystal Sun, its $10B vertically integrated solar factory near Houston, Texas.
The plant will make everything from silicon ingots and wafers to finished cells and panels, with operations targeted for Q1 2029.
@SERobinsonJr with a great flyover of the facility:
— TESLARATI (@Teslarati) November 9, 2026
Public filings first submitted in July under Texas’s Jobs, Energy, Technology and Innovation Act describe a plant that would manufacture the full solar chain: everything from silicon ingots, wafers, coated cells, and finished modules.
Tesla projects 9,712 permanent jobs by 2033, ramping from roughly 1,900 positions in the first year of operations, plus a peak of about 1,147 construction jobs. Construction is targeted for 2026–2028, with commercial production beginning in the first quarter of 2029. An accompanying economic analysis estimates the project could add roughly $107 billion to Texas GDP over several decades.
Local incentives have cleared major hurdles. Lamar Consolidated Independent School District unanimously approved school-tax limitations in September, and Fort Bend County commissioners approved a package of abatements and related agreements in late October that could extend equipment tax breaks for as long as 35 years.
Tesla had previously indicated it was evaluating a competing out-of-state location.
The effort fits broader statements by Musk that Tesla and SpaceX are each working toward 100 gigawatts of annual U.S. solar manufacturing capacity. If built as described, Project Crystal Sun would stand as one of the largest domestic attempts to create a fully integrated solar supply chain on American soil.
While Tesla has not issued a formal groundbreaking announcement, the visible site preparation and high-profile social media activity represent a concrete step forward for a project that has moved from confidential filings to active earthworks in a matter of months.
Energy
Taiwan power firm bets big on Tesla Megapacks as AI data center thirst grows
Taiwan’s Apollo Power orders 260 Tesla Megapacks, betting AI data centers will need more electricity.
A Taiwanese power company has ordered 260 Tesla Megapack 2XL units, roughly 1GWh of storage, betting that electricity rather than chips will decide how fast AI data centers come online. Apollo Power signed the contract with Tesla’s Taiwan energy arm on October 8, according to the company’s filing with the Taiwan stock exchange.
The filing says the units are meant for behind the meter storage and resilient grid projects, with delivery in batches from the end of 2027 and sites operating in 2028. Apollo and Tesla did not disclose a price, citing a confidentiality agreement. Apollo plans to pay for the equipment through a cash capital increase and bank financing, and it noted the purchase is not revenue and does not mean it holds firm orders from its partners.
Biggo reported that only about 33 units are under signed customer contracts, with roughly 150 more in negotiation. The same report put total project investment near NT$130 billion, but that figure includes installation work, with the equipment itself making up about 40 to 50 percent. In other words, a large share of this order is Apollo reserving supply ahead of demand. Apollo’s chairman told local media global large storage supply is tight, which is why the company locked in the units early, according to Yahoo Taiwan Finance.
Apollo also launched an AI data center and grid resilience alliance with Phison, Gigabyte and Shihlin Electric. The pitch rests on a pilot at Phison’s Zhunan plant, where Apollo and Tesla Energy Taiwan installed grid forming Megapack 2XLs in June. Tesla Energy Taiwan general manager Sun Hsiao-Han said the project went from demo to 1GWh in four months, and that Tesla Energy has deployed more than 50GWh worldwide.
Taiwan’s cabinet has approved amendments that would require large energy users to install their own generation and storage, which gives enterprise storage a regulatory tailwind.
The deal fits a pattern Teslarati has tracked. Tesla’s Megablock targets 1GWh commissioned in 20 business days, a pitch aimed squarely at fast moving data center builds. Megapacks already back xAI’s Colossus in Memphis and a 400MW AI campus in Brazil. Sun Media adds that Megapack 2XL was named among the first products in Nvidia’s DSX Ready qualification for battery storage in AI factories.
Deliveries are more than a year away, so the real test is how much of that 260 unit order turns into signed customer contracts.
Energy
Tesla Model 3 and Model Y can now do what only Cybertruck could
Tesla Model 3 and Model Y can power your home with Powerwall 3 during outages.
Tesla has turned its two top sellers into backup batteries for the house.
Tesla Energy announced on Tuesday that Powershare Home Backup is now available for new Model 3 and Model Y vehicles paired with a Powerwall 3, saying the car can “extend your home backup by over 2 days.” Minutes later, Tesla’s main account quoted the post with a broader pitch: “With Powerwall 3, every Tesla can now serve as your home’s backup battery.”
Until this week, the Cybertruck was the only Tesla that could send power back into a home, and that capability only began working alongside Powerwall 3 last month, after years of ambitious targets.
Tesla’s updated Powershare page says every Model 3 and Model Y ordered in the U.S. or Puerto Rico on or after October 1, 2026 can use the feature. Some, but not all, earlier cars also qualify. Owners can check on the touchscreen under Software, then Additional Vehicle Information, where a capable car shows “Powershare Support: Enabled.” As Electrek reported, bidirectional power on the two cars runs through an inverter Tesla calls PCS2 Lite, and the company has not said when that part entered production on each trim.
The home side is simpler. A house that already has a Powerwall 3 and either a Wall Connector 3 or Universal Wall Connector needs no additional equipment, and Tesla says compatibility is enabled through a software update. When the grid drops, the Powerwall and the car work together, with up to 11.52 kW of continuous power available. Tesla’s “over two days” estimate assumes a home using 30 kWh per day and a car starting at a 90 percent charge. Standard trims are rated for up to two days, while the Cybertruck adds more than three.
There are limits. Powerwall 2 and Powerwall+ support is listed as “coming soon.” Model S and Model X are not included, and Grid Support, the program that lets Cybertruck owners in Texas send power back to the grid during demand spikes for bill credits, is not available for Model 3 or Model Y.
The rollout also lines up with something Elon Musk said more than three years ago. At Tesla’s March 2023 Investor Day, Musk said, “I don’t think very many people are going to want to use bidirectional charging, unless you have a Powerwall.” Tesla has now shipped the feature for its volume cars with exactly that requirement attached.
The Powerwall pairing was the hard part on Cybertruck. Tesla told owners in December 2025 that Powershare with Powerwall had been pushed to mid 2026, and lead engineer Wes Morrill explained that two devices capable of forming a home’s grid have to negotiate which one leads during an outage, across multiple generations of hardware. With that work done for the truck, Tesla was able to extend it to the Model 3 and Model Y within a month.
Ford and GM have offered home backup from their EVs for several years, but both require a separate inverter and backup hardware. Tesla’s version leans on equipment many Powerwall 3 owners already have on the wall. Powershare for the two cars also ships as part of software update 2026.38.3, the same release that began delivering Halloween Mode on Tuesday.
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