The most innovative companies for energy in 2025

The global energy transition has been on an extraordinary tear in recent years, one that even President Donald Trump, with his dismantling of U.S. climate policy, will struggle to reverse. Propelled by record levels of public and private investment, utility-scale solar and wind power accounted for close to 90% of all new energy build-outs in the first nine months of 2024, a nearly 30% surge over 2023.

Still, the low carbon, electrified future can’t come quickly enough. The surge in energy consumption by data centers, electric vehicles, and manufacturing is putting a strain on an already struggling electrical grid, and pushing up planet-warming pollution: Alongside all the clean energy, the amount of energy derived from oil and coal and natural gas are also hitting all-time highs. The heavy-duty chips used to train AI models and infer outputs are especially demanding: running and cooling the data centers they fill already uses as much electricity each year as Italy, which has the eighth-largest GDP in the world. With all these greenhouse gasses, we’re likely to need even more cooling: January to June of last year was the planet’s warmest six-month stretch in 175 years.

This year’s Most Innovative Companies in Energy are meeting the challenge with advances that stretch from microgrids to giant batteries to the fan motors that keep data centers and the rest of the economy humming along. By assembling giant battery systems, Powin is helping ease the transition to cleaner energy sources and optimizing grid performance, while Intersect Power is building up capacity before the grid even arrives, by working “behind the meter” to combine battery storage with solar farms and, soon, Google’s data centers. Others are cooking up new ways to store all that wind and solar energy: If Antora gets its way, those batteries could someday be giant blocks of carbon; if Form Energy does, they could also be big containers filled with water and iron. Meanwhile, Infinitum is removing iron, at least from the innards of the conventional motor; by replacing the heavy stuff with printed circuit board, it’s cutting motors’ energy by 20%. That could help lighten the load of data centers and all the other places that rely on fans and conveyors—a welcome reminder that even subtle innovations can have massive impacts. 

1. Budderfly

For helping resource-hungry businesses get more energy efficient at no upfront cost

Managing power consumption and squeezing out more efficiency gains are often cited as critical tasks for building a more sustainable, lower-carbon economy, but they can be an unsexy afterthought. Budderfly simplifies and automates the process for businesses that often can’t take on the investment themselves, providing energy efficiency upgrades and equipment installations (more efficient HVAC systems and refrigeration equipment; LED lighting; smart thermostats; solar panels, and a suite of sensors), with no upfront cost to the business. Customers then pay Budderfly up to 5% less than what they would have paid their electric company before the upgrades, while Budderfly keeps the rest of the resulting savings. 

By tapping its deep pool of usage data, analytics, and energy billing expertise, the Connecticut-based company is betting it can cut most clients’ energy bills by 30%. Last year, Budderfly said it reduced its customers collective energy consumption by 43% compared to the previous year, resulting in a total savings of over 219,1000 metric tons of CO2 emissions, comparable to the emissions from driving an average gasoline-powered vehicle more than 560,000,000 miles.

Helping cash-strapped businesses achieve energy savings isn’t a completely new idea, but Budderfly’s simplified contracts and cloud-based platform have made it easier to onboard small- and mid-sized commercial and nonindustrial facilities. And its rich pool of data has helped sharpen the company’s ability to pick likely efficiency “winners.” Last year, it expanded its portfolio to more than 7,000 facilities—including franchises like McDonald’s, Orangetheory, and Applebee’s—doubling its annual recurring revenue to more than $200 million.

And the company is leveraging the power of its growing customer network for even bigger rewards: after acquiring the distributed energy management unit of Sunverge Energy, Budderfly has begun gathering its business customers into virtual power plants, or VPPs, allowing it to better orchestrate and optimize localized energy use. The program, now being tested at 10 sites around the country, also promises a new revenue stream to customers who feed energy back into the grid. In June, the startup also expanded into water management, and has already added more than 400 water accounts. 

The company’s one-of-a-kind model—taking on costly energy upgrades for businesses that don’t have the capital and then sharing in the benefits—isn’t cheap. But even if the Trump administration cancels a potential monster loan from the Department of  Energy, the company has built a war chest. To continue its expansion into the government sector and beyond, in January, Budderfly secured $400 million in debt financing from Nuveen and Vantage Infrastructure, bringing its total financing to nearly $1 billion. 

All this from a company that only launched in 2016, at first by selling a device to help monitor electricity use. “There are 60 different things you could do to manage [resources] better,” says founder and CEO Al Subbloie. “But the customer simply wants an outcome. So I said, ‘I’ll shift my deliverable to that.” 

Read more about Budderfly, honored as No. 25 on Fast Company’s list of the World’s 50 Most Innovative Companies of 2025.

2. Infinitum

For upgrading the electric motors in data centers and elsewhere to be smaller, quieter, and more efficient

The explosion of AI has sent data center power demand surging, with 30% to 40% of that energy going to motors for cooling equipment. Here and elsewhere, most motors deliver more horsepower—and thus use more energy—than are actually needed, so Infinitum redesigned the motor to be dramatically more efficient, by replacing the heavy iron and copper core of the conventional electromagnetic motor with printed circuit boards, and adding a variable frequency drive that allows users to adjust the power supply as needed.

The latest generation of its Aircore EC system—unveiled in 2024 for use in data centers, HVAC equipment, pumps, and industrial applications—is sized according to need, tailored to exact horsepower, torque, speed, and voltage requirements, and built with 60% less copper and none of the heavy iron used in most motors. A new lower voltage option eliminates the need for a step-down transformer, improving energy efficiency and reducing equipment complexity. And with easily replaceable parts, a modular design helps further lighten the motors’ environmental footprint.

The result, says Infinitum, is a motor that is upwards of 20% more efficient, in addition to being smaller, lighter, and quieter than conventional systems. More than just data centers stand to benefit: Electric motors are among the hungriest energy consumers on the planet, accounting for about 70% of the electricity used by industrial businesses, and up to 40% of all electricity use worldwide.

For now, the energy-intensive AI boom is helping drive growth. In 2024, Infinitum doubled its data center deployments and ramped up its revenue by 91% over the previous year. After raising an additional $35 million in a Series E funding round, in November it won a $34 million grant from the Department of Energy to begin work on a new, more efficient factory in Rockdale, Texas. By the end of the year, Infinitum says its existing plants in Mexico will be able to produce 200,000 motors, with efficiencies equivalent to keeping the electricity from 40,000 homes annually off the grid.

Read more about Infinitum, honored as No. 19 on Fast Company’s list of the World’s 50 Most Innovative Companies of 2025.

3. Anthro Energy

For building lighter, safer, longer-lasting and super-durable lithium-ion electrolytes

Most lithium-ion batteries are made using a highly flammable liquid electrolyte, which can be a problem if the battery fails or overheats. But Anthro Energy’s “advanced” electrolyte material isn’t like other kinds: Made with a patented, bendable polymer, it’s not flammable, and it provides a mechanical strength that prevents short circuit incidents while helping the battery achieve improved cycle life.

In 2024, just three years after spinning out of Stanford University, the company marked its first commercial implementation, announced a flurry of safety and performance advances, and watched its electrolyte breeze through rigorous U.S. Army tests, including the kind of forceful penetration, impact, overheating, and overcharging that easily results in fires in conventional batteries. While manufacturing costs are still higher than traditional electrolytes, Anthro’s semi-solid substance can be conveniently injected into existing battery designs, lowering barriers to scalability. (Its newest electrolyte formula, called Anthro Proteus, changes into a solid inside the battery during formation.) Already, Anthro says it counts “household name” electronics firms among its customers, as well as the Department of Defense, which is using its batteries for vehicles and other applications.

Now equipped with $20 million in Series A financing and $18.4 million in tax credits, Anthro is planning to build a large-scale factory inside an existing manufacturing site in Louisville, Kentucky. The company envisions that the 25 GWh facility will produce 12,000 metric tons of advanced electrolytes each year, create 114 full-time jobs, and serve as the first large-scale advanced electrolyte production facility on U.S. soil.

4. Form Energy

For using little more than rust to build giant, safe batteries that keep the grid running smoothly

Integrating renewable energy sources like solar and wind into the power grid is dependent on long-duration battery storage. Form Energy’s shipping container-sized solution harnesses iron, water, air and rust, in a process that can store energy for days or even weeks, at a lower cost and with greater safety than more conventional batteries. Each battery is a 40-foot container filled with cells that include a plate of iron submerged in water with dissolved salts. As the battery discharges, it pulls in oxygen and the iron starts to rust. When it charges, the oxygen is released from the iron, returning it to an unrusted state.

The systems have yet to be deployed at utility scale, but the company has managed to rack up more commercial orders than most long-duration energy storage startups, with 14 GWh of projects in the pipeline. In July, just a year after first breaking ground, Form completed construction of its first large manufacturing plant, a 550,000-square-foot facility inside a former steel mill in West Virginia. And with Minnesota’s Great River Energy, it’s planning to switch on its first deployment in Cambridge, Minnesota, in late 2025. 

Last year Form also won $147 million in funding from the Department of Energy to deploy a giant battery system in a former paper mill in Maine. When completed in 2028, it will be the largest battery installation on Earth, capable of discharging 85 megawatts of power for up to 11 hours in a particularly strained part of New England’s grid. Recently, the company notched $405 million in a Series F funding round, including investments from Bill Gates’ Breakthrough Energy Ventures and Energy Impact Partners. Another investor, GE Vernova, said it would partner with Form to boost its manufacturing and supply chain operations.

5. ULC Technologies

For using robots to help utilities quickly fix underground electric and gas lines

Upgrading the grid for reliability and resilience will be critical for the future economy, but all those cables also mean a lot of hands-on work in hazardous conditions. ULC built a robot designed to automate the splicing and termination of medium voltage cables, enhancing the power grid while significantly improving utility worker safety. Developed through a collaboration with Con Edison, the machine aims to automate cable end preparation: It’s capable of stripping, shorting, and cutting the cable from outside the manhole with no human intervention. This reduces worker exposure to high voltages and improves the accuracy and safety of thousands of cable splices performed every year.

After a medium voltage feeder cable outage last February, Con Edison asked ULC to field trial the bot for the first time in an emergency scenario. The machine completed the world’s first fully remote medium voltage cable end preparation with no human intervention, taking approximately 30 minutes for each phase of the cable.

The Hauppauge, N.Y.-based company already has deep experience in sub-surface robotics: Since it was first used in 2010, its signature robot CISBOT (Cast Iron Sealing Bot) has become an unparalleled tool for remote gas line maintenance. Many cast iron mains in the U.S. and the UK were laid during the Victorian era, and the switch to natural gas in the 1970s has accelerated erosion of the sealants that protect their joints. Once inside a pipe, CISBOT snakes hundreds of feet in either direction and performs sealing remotely, enabling utilities to extend the lifespan of their pipes by 50 years while avoiding dangerous human work and extensive digging. New versions of the robot trialed in 2024 bring the technology to smaller and medium-diameter gas mains. At the same time, its Drawdown Compressor Technology helps repair crews reduce emissions by extracting natural gas from the pipeline that would otherwise be released into the atmosphere and re-introduce it back into the active gas network. 

Last year ULC signed new contracts with two large utilities in New Jersey, where regulations have mandated faster leak repairs, and continued to expand its multi-city fleet of CISBOTs, with over 60,000 joint remediations and counting. In 2024, ULC also received recognition from the U.S. Air Force’s innovation arm for a completely different kind of robot concept: a machine, developed in partnership with materials startup Group IQ, that’s designed for another kind of dangerous job: rapidly repairing bombed airfields.

6. Antora Energy

For storing electricity from renewables in the form of white-hot heat

Wind and solar are too often stranded from the storage that can make them as cheap and reliable as coal. Antora’s shipping-container-sized thermal batteries, made of three-foot blocks of carbon, store electricity from renewables in the form of white hot heat, which can be converted to electricity or simply used as heat for industrial processes. That option is critical: Most heavy industries depend on high temperatures that renewables and many types of long duration storage can’t provide.

In 2024, the six-year-old company began production at its first dedicated factory near its headquarters in Sunnyvale, California, and demonstrated breakthrough heat-to-electric conversion efficiency for its thermophotovoltaic cells (similar to the technology solar panels use to generate electricity). It also reached the highest temperature that had been demonstrated for thermal batteries at full scale, storing energy above 1,800°C.

The company’s investors include heavyweights like Laurene Powell Jobs’ Emerson Collective, the Nature Conservancy, and Bill Gates’ Breakthrough Energy Ventures, most recently through a $170 million Series B funding round, among the biggest climate tech deals in 2024. Last year Antora also earned a $14.5 million award from the U.S. Department of Energy’s ARPA-E to unlock commercial-scale manufacturing, and forged partnerships with Con Edison, Shell, and Summit Materials.

7. Vertiv

For taming the energy demands of hyperscale AI data centers

Many of the environmental costs of AI relate to just keeping those complex chips from overheating: cooling still accounts for roughly 40% of data centers’ massive and steadily growing electricity consumption, Vertiv, a master in precision air conditioning, has been trying to meet that demand with new approaches to cooling and power management, including CoolPhase Flex, an architecture launched in 2024 that integrates liquid cooling with air-based technologies in a single package.

Orders are also growing across the U.S. and Africa for its DynaFlex BESS, a new battery energy storage system designed to let data centers replace their backup diesel generators and seamlessly switch between different types of renewable power, including a hydrogen fuel cell option. It also launched a prefabricated modular data center system, designed to reduce the time to deploy AI infrastructure by as much as 50%. It’s an 80-year-old company, with a history that dates back to the invention of the computer-room cooling systems by Ralph Liebert, who sold IBM its first cooling in 1965. But lately, its data center expertise has helped its stock price soar more than tenfold in the last two years, as the cold realities of blistering AI demand began to set in.

8. Intersect Power

For combining batteries, renewables, and lots of cash to green the grid faster

In Intersect Power’s home state of Texas, where severe storms have cut power and left hundreds dead over the past decade, upgrades to the grid can’t come soon enough. Rather than waiting for transmission infrastructure to come to its massive solar-plus-storage facilities, the startup is focused on co-locating with customers, be they data centers, factories, or green fuel plants. That model allows the company to raise funding faster and build more quickly. In 2024, armed with $837 million in financing, it deployed three nearly 1 GWh battery-solar plants at lightning speed, assembling its battery energy storage systems with the help of one of the largest ever orders of Tesla’s utility-scale 3.9 MWh Megapacks.

Then, in November, it announced a landmark deal: a decade-long partnership with Google to build a set of energy parks where AI data centers will flourish alongside an estimated $20 billion in renewable energy and energy storage. Another round of funding—$800 million, led by Google and TPG—will help Intersect get started on the first park, which is set to open in 2027.

For the nine-year-old startup, working “behind the meter” is a speedy response to the sluggishness of grid connections and upgrades, and to a market that still doesn’t incentivize new battery storage. Originally a flipper of clean energy projects, now it operates its own sites, raising money through equity and loan financing priced according to the market, rather than with the less risky, long-term power purchase agreements that typically finance grid-scale projects. Over the next three years Intersect now expects to triple the size of its total portfolio.

9. Powin

For scaling up giant battery packs to the size of coal-fired power plants

Oregon-based Powin helps utilities integrate renewables into the grid with the help of its giant battery systems, built with a suite of sensors and software designed to manage performance and power down to the cell level. To make the green transition a little easier, in 2024, it released the Powin Pod, a compact battery system that holds 5MWh in a 20-foot container. The form factor allows utilities and developers to store up to 50% more energy in the same footprint, while on-board software allows administrators to track and predict cell temperature, voltage, performance, and other factors to ensure optimal operation.

After helping power the 2024 Super Bowl (with 564 batteries at NV Energy’s Arrow Canyon solar farm in Moapa, Nevada), in July the company unveiled its latest giant storage project, at a former Michigan coal plant. Set to become the largest stand-alone energy storage site in the Great Lakes region when it opens in 2026, the Trenton Channel Power Plant will store 220 MW, or enough to power about 40,000 homes for a day. 

This year Powin anticipates the launch of Australia’s Waratah Super Battery project, set to be one of the world’s largest battery systems. In October, Powin secured $200 million in debt financing from KKR to help advance its innovation and expansion in the U.S., Europe, and Australia. It also announced a partnership with BHE Renewables to deliver what would be one of the country’s largest solar and storage microgrids, in Ravenswood, West Virginia, which will provide renewable energy to manufacture titanium for the global aerospace industry. Powin is set to begin initial deliveries to the site this year, with plans to reach full capacity in 2027.

10. 24M Technologies

For solving range anxiety (and battery fires)

The MIT spinout 24M has been developing a battery designed to be safer, cheaper, cleaner, and longer-lasting. That’s because it uses a semi-solid lithium metal as an electrolyte, rather than lithium-ion, which gives the battery more energy density and requires fewer materials, along with sensors and a unique separator that helps prevent the aberrations that cause shorts and fires. A new electrolyte addition, Eternalyte, enables what 24M calls a “1,000 mile battery,” while a process the company calls LiForever makes 98% of a battery’s material recyclable.

The Cambridge, Massachusetts-based company builds its own cells and licenses its technology to other battery companies and automakers, including a large unnamed manufacturer that began taking delivery of its separator-equipped 1,000-mile cells in late 2024. (One likely candidate is Volkswagen, which acquired a 25% stake in 24M in 2022.) Japanese electronics giant Kyocera, which was the first 24M partner to commercialize the startup’s SemiSolid electrode manufacturing process, also announced plans to double production of the cells for use in its residential energy storage system. In September, the startup opened a new factory in Thailand, where it began producing cells for an Indian automaker, and closed another financing round totaling $87 million, valuing the company at $1.3 billion.

Explore the full 2025 list of Fast Company’s Most Innovative Companies, 609 organizations that are reshaping industries and culture. We’ve selected the companies making the biggest impact across 58 categories, including advertising, applied AI, biotech, retail, sustainability, and more.