Whether it’s to keep the lights on after a natural disaster or just to avoid peak energy rates, more people than ever are adding battery energy storage to their home solar systems. With some 45% of home solar customers saying yes to home batteries last year, the big question isn’t whether or not to get one – it’s what kind to get.
Two options stand out: lithium ion, and vanadium flow. Here’s the information you need to make the right choice.
Lithium-ion or “li-ion” batteries are the batteries you’re probably most familiar with. They’re used in most laptops, smartphones, and EVs – and for good reason!
That sort of market ubiquity and like-for-like competition among vendors and manufacturers has driven per kWh costs down continually. And those lower costs? They’re driving adoption in big solar markets like California, Texas, and Hawaii, where between 68 and 100% of residential solar quotes have home backup batteries “attached,” and Tesla – thanks to the slick new Powerwall 3 and its integrated solar inverter – is the most quoted brand.
Most quoted home solar batteries
Screencap; via EnergySage.
As good as they are, li-ion batteries aren’t perfect. Li-ion batteries degrade over time, losing capacity with use and needing to be replaced after 10-15 years. And, while the risk of a lithium battery fire is increasingly and exceedingly low, it’s also very real – leading to intense fires that are difficult to put out with conventional fire-fighting methods.
Vanadium flow batteries address both of those shortcomings, offering 20-30 years of usable service life without degradation and with little (or, depending on who you believe, zero) chance of the sort of “thermal runaway” that leads to li-ion battery fires.
The energy capacity (kWh) of a flow battery is determined by the volume of the electrolyte fluids in the tanks (bigger = more), while the power output (kW) depends on the size of the electrochemical cell stacks.
That is, of course, to say that a comparable vanadium flow battery will be significantly bigger and more complex than a li-ion solution. That added complexity, combined with the relative rarity of vanadium flow batteries on the market, mean that the same economies of scale and manufacturer/vendor competition haven’t acted to drive costs down in the same way that they have in the li-ion space.
Spec + price comparison
Battery
Usable Capacity (kWh)
Continuous Power Output (kW)
Round‑Trip Efficiency
Average Price per kWh*
Coupling
Tesla Powerwall 3
13.5
11.5
97–97.5%
$1,133
DC or AC
StorEn Vanadium Flow*
30
5
~75–80%
$500–$900
DC or AC
*Based on StorEn’s modular 30 kWh system. The company doesn’t post pricing (or I couldn’t find it), and the prices shown are based on Google and Reddit searches. Prices may vary by region, so click here to get localized pricing.
As you can see, there are pros and cons to both setups. The li-ion batteries are proven tech, but the Gen X-ers and Boomers out there will tell you: 10 years is not a long time, and the thought of replacing your batteries (or, more likely, your inverter) every ten years isn’t a pleasant one.
That said, the vanadium flow batteries I could find seem to “top out” at about 5 kW of continuous output – so if your AC draws more than 5 kW continuously (possible in a large Texas or Arizona home or barnodminium), the system won’t be able to power it.
The final conclusion, then, comes down to what you value as an individual. If you want maximum output to keep the lights on and ride out a power interruption like nothing happened with a decade of reliability baked in, a li-ion setup might work. If you’re primarily interested in keeping the food and medicines in your refrigerator fresh, think replacement is a hassle, and the thought of a one-in-a-million battery fire taking out the 90-point Lancia Aurelia B20 GT that lives in your garage keeps you up at night, the “absolutely will not burn” vanadium flow option might be a no-brainer.
You don’t need a home solar panel system to reap the benefits of home battery backup. But you’ll get the most out of your system when you pair them together — especially if your utility doesn’t pay you much for the excess electricity your solar panels generate and send to the grid.
If you’re considering going solar, it’s always a good idea to get quotes from a few installers. To make sure you find a trusted, reliable solar installer near you that offers competitive pricing, check out EnergySage, a free service that makes it easy for you to go solar. It has hundreds of pre-vetted solar installers competing for your business, ensuring you get high-quality solutions and save 20-30% compared to going it alone. Plus, it’s free to use, and you won’t get sales calls until you select an installer and share your phone number with them.
Your personalized solar quotes are easy to compare online and you’ll get access to unbiased Energy Advisors to help you every step of the way. Get started here.
FTC: We use income earning auto affiliate links.More.
OpenAI on Thursday said it is launching a Stargate-branded AI data center in Norway, marking its first foray into Europe with such a project.
British firm Nscale will design and build the site as part of a 50-50 joint venture with Norwegian energy infrastructure firm Aker.
OpenAI will be a so-called “off-taker” in the project, meaning it will effectively buy capacity from the data center.
“Part of the purpose of this project is to partner with OpenAI and leverage European sovereign compute to release additional services and features to the European continent,” Josh Payne, CEO of Nscale, told CNBC in an interview on Thursday.
The site aims to deliver 100,000 NVIDIA graphics processing units (GPU) by the end of 2026, “with the intention to expand significantly in the years ahead,” OpenAI said in a press release. The companies said the data center will run entirely on renewable power and have 230 megawatts of capacity, making it one of the biggest in Europe.
Nvidia’s GPUs have become the de facto choice of chips for data centers because of their ability to handle large AI workloads.
For the Norway project, Nscale and Aker have each committed around $1 billion to the initial 20MW phase of the project. The site will be located in Kvandal, just outside Narvik in northern Norway. The companies said the region is characterized by “abundant hydropower, low local electricity demand, and limited transmission capacity.”
Payne declined to comment on how Nscale would fund this project or the financial benefits of the project to the company. The CEO said there were no plans for additional Stargate data centers but that Nscale has its own “robust European expansion plan.”
OpenAI has looked to take this initiative globally. In June, the company and its partners announced plans to build a Stargate campus in the UAE.
Europe has meanwhile been pushing the concept of “sovereign AI,” requiring data centers and AI workloads to be located and processed on European soil.
Payne said Europe has two “problems” — the first is that it does not have enough computing capacity, and the second it is “very fragmented.”
“What the continent needs is large AI infrastructure projects deploying compute [power]. The ecosystem can consume from the project to build AI products, to generate productivity growth and economic benefit,” Payne said.
In a trip to Europe this year, Nvidia CEO Jensen Huang urged the continent to build more AI infrastructure. French AI company Mistral announced plans to use Nvidia’s GPUs in a new data center planned for France.
The brand logo of the mineral oil and natural gas company Shell plc can be seen at a filling station of the company in Nuremberg (Bavaria) on July 25, 2025.
Britain’s Shell on Thursday reported better-than-expected second-quarter profit and maintained the pace of its shareholder returns, despite the impact of lower global oil and gas prices.
The energy giant posted adjusted earnings of $4.26 billion for the three months through June, beating analyst expectations of $3.87 billion, according to an LSEG-compiled consensus.
A separate, company-provided analyst forecast had expected Shell’s second-quarter profit to come in at $3.74 billion.
Shell reported adjusted earnings of $6.29 billion over the same period last year and $5.58 billion in the first three months of 2025.
The results come shortly after the London-listed firm flagged weaker trading results at its integrated gas division and losses at its chemicals and products arm.
Shell also announced another $3.5 billion in share buybacks over the next three months, keeping the pace of its shareholder returns. It marks the 15th consecutive quarter of at least $3 billion in buybacks.
“The backdrop of the macro has been challenging, and what I would say is we continue on the momentum that we have in transforming Shell,” CEO Wael Sawan told CNBC’s “Squawk Box Europe” on Thursday.
“On all measures, [I’m] pleased with that performance. And on the trading side, indeed, despite difficult macro, pleased with how the team has performed,” Sawan said.
Shares of Shell were up 2.5% at around 9 a.m. London time (4 a.m. ET).
Value creation
In March, Shell announced plans to prioritize shareholder returns, ramp up the cost of savings and double down on its liquified natural gas (LNG) push. The strategic update was designed to bolster its commitment to value creation, while maintaining focus on “performance, discipline and simplification.”
The plan appears to have been well received by investors. Shell’s share price has outperformed many of its European and U.S. rivals so far this year, notching gains of 8%. By comparison, Britain’s BP is up 3%, France’s TotalEnergies is down 2% and Exxon Mobil is up 4% over the same period.
Notably, Shell recently dismissed speculation about a possible takeover bid for BP, saying in late June that it had “no intention” of making an offer for its struggling domestic rival.
Asked about the prospect of acquisitions and whether the current state of play means bigger is better for oil companies, Sawan replied: “I don’t buy bigger is better. I think you have to drive it from a value perspective.”
Shell’s CEO said scale is not of concern for the world’s largest trader of liquified natural gas (LNG).
“It is how do we leverage that scale by focusing on the areas where we have competitive strengths and the areas where can create value,” he addd.
‘You can be sure of Shell’
Shell on Thursday said that it achieved structural cost reductions of $800 million through the first six months of 2025, bringing cumulative reductions since 2022 to $3.9 billion. Earlier in the year, the company set a cost reduction target of $5-7 billion by the end of 2028.
The company’s net debt, meanwhile, came in at $43.2 billion at the end of the second quarter, up from $41.5 billion on a quarterly basis.
Shell’s Sawan repeated his comments from earlier in the year when asked about the prospect of the company moving its listing from London to New York, saying it is not a live discussion.
Customers pump gas into their vehicles at a Shell station on April 10, 2025 in Miami, Florida.
Joe Raedle | Getty Images
“Part of the reason is actually we have been outperforming. We have been able to just stick to our own story, just deliver on what we say we’re going to do. At Capital Markets Day we used the old tag line: ‘You can be sure of Shell,'” Sawan said.
“On the back of that, we feel more and more confident that our message is getting through to those pools of capital that want to invest in this differentiated investment thesis that we have,” he added.
It’s a big day for upstart electric semi truck manufacturer Windrose. The company has lined up what could be a landmark, $60 million deal and announced plans to being shipping its innovative HDEV trucks to South America.
ChinaTrucks is reporting that Windrose has lined up a deal to supply several hundred of its long-range, battery-powered heavy-duty trucks to US-based, zero emissions logistics company Nevoya that, once finalized, will represent the startup’s largest North American order to date. The agreement, which is reportedly valued at more than 430 million yuan (approximately $60 million, as I type this), has initial deliveries of the Windrose R700 BEV semi planned by the end of 2025, with full deployment expected by the end of 2026.
The company used its own electric trucks to complete the logistics process between warehouses and ports in both Shanghai and Los Angeles, achieving what it’s calling a fully zero-emission transport loop. Windrose CEO Wen Han posted the knock-down kits arriving at the Port of Long Beach a few days ago, and it appears that these could be the first of hundreds of electric semi trucks destined for deployment at Nevoya.
Advertisement – scroll for more content
Expansion plans
Windrose R700 electric semi truck; via Windrose.
At the same time, Windrose announced expansion into its 5th continent, thanks to a partnership with Chilean logistics firm Trailerlogistics Sudamerica.
Chile has a goal of reaching 100% zero-emission sales of freight transport and intercity buses by 2045. This aligns with its broader National Electromobility Strategy, which targets carbon neutrality by 2050. Chile is ranked as the 5th largest economy in Latin America by nominal GDP and 46th in the world (just above Finland and Portugal). Further, Chile has the highest per-capita GDP in Latin America. In 2024, there were 14,267 trucks sold in Chile, according to National Automotive Association of Chile.
For their part, Trailerlogistics Sudamerica seems excited by the prospect of electrifying their fleet with Windrose. “I am completely convinced Chile is the perfect market to start with Windrose in South America,” says Hernan Searle Ferrari, the company’s founder and CEO. “Apart from having totally open trade agreements with all international markets, Chile boast world-class highways and a unique geography; from the desert in the north, all the way south down to Antarctica, covering a total of 4000km. This will allow us to continue developing the dominance of our long-haul EV technology in all terrains.”
The first Windrose trucks will arrive in Chile to begin route testing with Trailerlogistics later this year, with a stated goal of deploying up to 100 trucks by the end of 2026.
If you’re considering going solar, it’s always a good idea to get quotes from a few installers. To make sure you find a trusted, reliable solar installer near you that offers competitive pricing, check out EnergySage, a free service that makes it easy for you to go solar. It has hundreds of pre-vetted solar installers competing for your business, ensuring you get high-quality solutions and save 20-30% compared to going it alone. Plus, it’s free to use, and you won’t get sales calls until you select an installer and share your phone number with them.
Your personalized solar quotes are easy to compare online and you’ll get access to unbiased Energy Advisors to help you every step of the way. Get started here.
FTC: We use income earning auto affiliate links.More.