Would you take a payment to ramp down your electricity use? Would it change anything if you were doing so to help power a local data center?

Google just signed a new deal to help pay for a virtual power plant (VPP) in the largest power grid in the US. The agreement is with Voltus, a leading VPP and distributed energy resources platform.

Voltus will set up the virtual power plant, grouping together devices like electric vehicles and smart thermostats. It’ll pay customers to participate, and the company will dial back power or use the stored energy during times when the grid is stressed. Google will foot the bill for setting it up, and the extra capacity generated by the project will help run its data centers in the region.

This is one of the most concrete examples so far of a tech giant using a VPP to help meet energy demand for data centers. But there are still some lingering questions about just how far this sort of program can go, and what the limits are.

Last year, it felt as if everyone was talking about data center flexibility. A high-profile study from Duke University found that if data centers agreed to decrease their energy demand for roughly 40 hours per year, a whole bunch of them (about 100 gigawatts’ worth) could come online without making new power plants or transmission equipment necessary.

The underlying reason is that our power grid is designed not for our average energy use, but for the absolute maximum: the brutally hot July evening when everyone is blasting their air conditioners, watching Love Island, and microwaving popcorn. If a data center is willing to refrain from pulling so much power during those high-stress times, the grid can happily support it the rest of the year.

One lingering question here is about incentives: How would you get data centers to agree to this? After all, they might not have a very flexible load, especially now that AI use is more widespread—training a model can easily be delayed or shifted, but customer demand is more immediate. Giving up computing capacity could mean losing revenue.

Regulation is one approach that could work here. One proposal in the US would allow new data centers to come online years sooner if they agree to lower demand when the grid is nearing its max.  And a new Texas law requires large users to switch to backup power or curtail their demand in emergency situations.

Another approach is for data center operators to pay for other people to be flexible.

Voltus announced a new program in September that allows data centers to finance flexibility on their local grid. The company calls it “Bring your own capacity.” Google is now the first named customer taking advantage of this program.

In the new agreement, Voltus will pay people who agree to participate in the virtual power plant. The plant will be part of PJM, the grid that covers much of the US East Coast. The company says it will be able to aggregate up to 100 megawatts of distributed energy resources each year. The plant should be operational in 2027, according to Voltus.

This isn’t Google’s first foray into flexibility; the company has agreements with utilities across the US to limit or shift its own energy demand, which can help free up grid capacity. As the company pointed out in a blog post earlier this year, though, there are limits on how flexible a data center can be, and not every facility will be able to ramp down its power demand.

“There is no one solution for expanding grid capacity and we’re continuing to explore all options, including the many avenues for load flexibility,” said Michael Terrell, Google’s global head of advanced energy, in an emailed statement in response to written questions.

Once again, I’m wondering about incentives here. These companies are asking homes and businesses to be flexible. Will they agree?

A recent study in California looked at local people’s willingness to participate in managed electric-vehicle charging. Essentially, the program pays people to give up control of when they charge their EVs. This is another way to help smooth out electricity demand and ease the burden on the grid.

The problem? Not many people signed up. With no economic incentive, only 1% of EV owners enrolled in managed charging. At $40 per month (about 15% of their power bill), only 4.6% did.

This is a different situation and a different region from the one in which Google is working with Voltus. (It’s worth noting that the companies aren’t sharing how much they plan to pay the participants, which will obviously be a big determinant in participation for this kind of project.) 

But this study shows that even with money on the table, people may not always jump at the chance to cede control of their electricity demand. And it certainly feels relevant that about 70% of Americans oppose AI data centers in their area, according to recent Gallup polling. 

Being flexible sounds like a great idea in theory, and these financed VPPs could provide an immediate route to meeting energy demand. But as we move from idea to implementation, it’ll be interesting to see whether trial runs work as intended.  

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Researchers say they’ve found a new way to extract lithium, a crucial metal used in the lithium-ion batteries that power electric vehicles and energy storage arrays. This new technique could be more environmentally friendly and cheaper than existing ones. 

The research was published today in Science, and a startup called Rock Zero is working to commercialize the process.

“At scale, we believe this will be the lowest-cost way of sourcing lithium in the world,” says Yet-Ming Chiang, one of the study authors, who is an MIT professor and a serial entrepreneur behind climate tech companies including Form Energy and Addis Energy.

The most economical way to get lithium currently is to extract it from brine, salty water that’s pulled the metal out of rock over the course of millennia. But this technique is geographically limited and currently requires vast tracts of land for massive evaporation pools. The more common tactic is hard-rock mining, where large bodies of ore are blasted apart, cooked at high temperatures, and processed using dangerous chemicals.

The researchers’ new method uses a weak acid to dissolve typically nonreactive silicate minerals. That frees not only the lithium but also other useful materials, including alumina and silica.

The origin story for this research, and the resulting company, came from another startup founded by Chiang, Sublime Systems, which makes cement using electrochemistry.

The team was trying to find a source of highly reactive silica in order to form stronger cement. One way to make reactive materials, which can bond easily with other materials, is to take a nonreactive material, dissolve it, and then allow it to become solid in a more reactive form. It’s not impossible to dissolve silicates, but the best-known way is to use hydrofluoric acid, an extremely dangerous chemical. Other fluorine-containing chemicals are candidates too, but some will produce hydrofluoric acid as a side product during reactions. 

Chiang drew inspiration from a previous home renovation project involving glass, which is made of silica. “I was remodeling a shower in Framingham, Massachusetts, about 25 years ago,” he says. “So when we started this project, I remembered that glass etching cream and thought, ‘What’s in that?’” 

The glass etching cream he remembered, which can be found on shelves at any craft or home improvement store, uses ammonium fluoride, a weak acid. And the MIT researchers discovered that in the right conditions, it can effectively dissolve silicate minerals without producing hydrofluoric acid in the process.

This chemistry could be useful for any silicate minerals—and there are a lot of them. But spodumene, the mineral that’s often mined for lithium, became a prime first target. (Chiang says a suggestion from Doug Wicks, one of the company’s advisors and a former ARPA-E official, pointed the team in spodumene’s direction.)

Today, a key step in processing spodumene ore is to roast it in a kiln at super-high temperatures. This causes a phase transformation, essentially puffing up the material and making the lithium more accessible.

By avoiding the need to reach these temperatures, you could save on energy costs and potentially reduce carbon emissions as well, says Camden Hunt, one of the authors of the study and the CEO and cofounder of Rock Zero.

Avoiding the kiln could also unlock the ability to use some ores that can’t be roasted properly, Hunt adds. Ore that contains too much iron won’t go through the phase change correctly, instead melting and turning into a glassy material.

The new process relies on simple stirred plastic tanks and takes place at temperatures up to about 95 °C (200 °F). The ammonium fluoride dissolves the silicates, which in earlier experiments allowed nearly all of the lithium inside the spodumene ore to be extracted within a couple of days. The researchers have since cut this time to under 12 hours, says Benjamin Mowbray, first author of the study and the CTO and cofounder of Rock Zero.  

The products (after some additional steps to clean them up) are lithium carbonate, which can be used to make batteries; alumina, which can go into a smelter to make aluminum; and cementitious silica, which can be added into concrete. And the acid can be reused in the same loop.

Chiang calls this “nose-to-tail” mining—using every part of the ore provided, like eating every part of a butchered animal.

The researchers are currently working to scale and optimize the process. The tanks in the lab in Cambridge, Massachusetts can handle three kilograms of spodumene concentrate in each batch. 

They have also estimated the cost of this process once fully scaled up. Assuming that the ammonium fluoride can be recycled at a high level, they should be able to extract lithium for less than $6,000 per metric ton. (They’ve identified a potential cheap industrial source of the acid as well, as an alternative to recycling it.) 

The total cost is projected to be lower than that of other processes used to extract lithium from hard-rock ore today, and it could be competitive with brine.

The team has designed a pilot plant and is looking for space to build it. The plan is to have construction done by the end of 2026 and start operating the facility in 2027. Talks are underway with potential partners in the mining industry.

One difficulty for new players in lithium extraction is the volatility of the market: Prices have seen huge swings in recent years, from a peak in 2022 to lows in late 2024 and a slow climb starting in early 2026. 

Rising prices might benefit new players like Rock Zero, but there are many projects that could come online if prices continue to rise, and that could bring the market right back down, says Simon Jowitt, chair of exploration geology at the University of Nevada, Reno. “People are waiting to see what happens with the lithium price,” he says. “It’s a crowded market, and there’s some big players out there.”

And even though batteries are driving up demand for lithium, the market is still relatively small, Jowitt adds: “That means it’s going to be volatile.” New lithium extraction technologies like Rock Zero’s will have to compete with methods used by existing giants, and there’s also the potential that technological alternatives, like sodium-ion batteries that don’t need lithium, could make the market more difficult to navigate, Jowitt says. He also thinks some of the company’s economic estimates could be optimistic.

For its part, Rock Zero’s team hopes not only to scale this technology for lithium, but to use it for other minerals in the future. As Mowbray says, “The Earth’s crust is made of silicates.”

This year, there’s been a wave of notable energy companies going public via IPO in the US.

The solar and battery company Solv Energy went public in February, to the tune of $6 billion. X-energy, which is building small modular nuclear reactors, did the same in April, and its stocks surged on its first day of trading to hit a $11.5 billion market cap. Most recently, the geothermal company Fervo Energy went public in mid-May, and its market cap is now about $12.4 billion.

Those are all success stories in the IPO world. And it certainly doesn’t feel like a coincidence that all these companies are racing to provide electricity in an era of rising demand (partly due to data centers). Let’s take a look at how these firms are doing, what this moment says about the grid, and what’s coming next. 

Let’s start with Fervo Energy, a company we’ve covered a lot over the years that’s working to develop enhanced geothermal energy. (We included it on our 2025 list of Climate Tech Companies to Watch.) While conventional geothermal requires finding specific spots with hot rock, water, and fractures to support a power plant, Fervo essentially uses fracking techniques to create the necessary conditions.

The company was founded in 2017, and it raised about $1.5 billion from investors over the years before its IPO.

Fervo’s first commercial project, Cape Station in Utah, is expected to have a capacity of about 500 megawatts. The first unit is set to start generating power for customers by October and the next two units by January 2027.

The new funding from the IPO could help the company scale. Fervo currently has over 600 megawatts’ worth of binding power purchase agreements. And it has leases for land that could together generate more than 40 gigawatts of electricity. (As of 2024, the entire US geothermal fleet had a capacity of just 4 gigawatts.)

The company also has an eye on cutting construction and drilling costs—its Cape Station plant is expected to cost about $7 per kilowatt, which is cheaper than new nuclear power plants but over twice the expense of building a new natural-gas plant in the US. 

X-energy also aims to provide reliable clean power: it’s part of the wave of next-generation nuclear companies working on small modular reactors. The company is building high-temperature gas-cooled reactors, which flow helium over self-contained pebbles of nuclear fuel. These reactors will each generate 80 megawatts of electricity, less than one-tenth the output of larger ones like Unit 4 at Plant Vogtle in Georgia, the most recent addition to the commercial nuclear fleet in the US.  

X-energy also saw its IPO go well, and prices surged in trading after the initial offering. One interesting tidbit here—the company had previously planned to go public in 2023 but decided against it because of difficult market conditions.

The company is still years away from demonstrating its technology in a commercial project. 

You may recall a story I wrote last year about its effort to build nuclear reactors at the site of a Dow Chemical plant in Texas. The company recently received a key environmental approval for that project, though it’s still waiting for the final green light from the Nuclear Regulatory Commission to start construction.

Finally, Solv Energy builds solar and energy storage projects, mostly for utilities and independent power producers. Solar and batteries are some of the cheapest and easiest technologies to add to the grid, so this one could get a lot of capacity online, quickly. The company already has 21 gigawatts’ worth of projects operational across 35 states.

Many companies in the energy sector are pinning their hopes on the rapid growth in data center construction and operation. The AI boom has transformed the energy landscape, pushing electricity demand higher in a country where it’s been relatively flat for the last decade or so. Solv Energy mentioned data centers over a dozen times in documents filed with the Securities and Exchange Commission before its IPO. 

And Fervo and X-energy are particularly connected to the tech giants driving AI. Google has been a longtime investor in Fervo and also pioneered what it calls its clean transition tariff with the company. Amazon is a client of X-energy as well as an investor; it reportedly owns close to 20% of the company.

Fervo and X-energy are also in industries that occupy a political sweet spot. President Trump and his administration have gone after wind power and other renewables, cutting off existing support and slowing approvals for new projects. Meanwhile, geothermal and particularly nuclear power have kept favor with the federal government and enjoyed continued tax credits and grant funding.

If a few big leaders cash through these IPOs, it could help investors feel more confident about supporting the energy sector, even if that money is concentrated in later-stage ventures like these rather than earlier-stage companies. 

We could see other firms, particularly in nuclear and geothermal, attempt a similar route in the year ahead.

A key thing to watch here will be whether Fervo and X-energy in particular can succeed in scaling up and deploying their technology. If either of these companies stumbles or misses a timeline, it could have ripple effects for those hoping to follow in these very lucrative footsteps. 

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.