Every six seconds, in a factory on the outskirts of Stockholm, a top-secret printer produces sheets worth thousands of euros each. These sheets contain 108 miniature solar cells destined for everyday gadgets—such as keyboards and headphones—that will revolutionize our interaction with technology. According to their creator, these innovations will even prompt us to reconsider our relationship with light.

Sweden might seem like an unlikely hub for a solar revolution, especially given its long, dark winters. However, this was a driving factor for Exeger co-founder Giovanni Fili, who sought to develop photovoltaic cells that could harvest energy from more than just sunlight. His company’s groundbreaking technology can generate electricity from virtually any light source, including candlelight and even moonlight, albeit slowly.

“Like algae at the ocean’s depths where it’s nearly pitch black, we can efficiently utilize very few photons,” Fili explains to The Independent. His T-shirt proclaims his company’s technology as “world-changing,” addressing the global energy demand while tackling significant environmental challenges.

Indoor solar panels have existed for decades, with solar-powered calculators debuting in the 1970s. However, the amorphous silicon cells used were too low-powered, fragile, and rigid for broader applications. A pivotal discovery in 1988 involving dye-sensitized solar cells (DSSC) by UC Berkeley scientists led to high-efficiency, semi-flexible, and semi-transparent cells, paving the way for commercial development.

Over 20 years later, Fili and fellow Exeger co-founder Henrik Lindström developed a new electrode material with 1,000 times better conductivity, forming the basis of their Powerfoyle cells. These cells, now produced at a commercial scale, eliminate the need for the traditional glass-covered panels’ silver conductors and are not sensitive to partial shading, enhancing their efficiency.

Powerfoyle cells are revolutionary due to their skin-like material, which can seamlessly integrate into a wide range of products while remaining waterproof, dustproof, and shockproof. “It works in any light condition, is more durable than any other solar cell in the world, is easy to manufacture, and can imitate any surface—leather, carbon fiber, wood, brushed steel. It’s also beautiful,” Fili says. “We can integrate into products already selling in billions of units per year.”

Exeger’s Stockholm facility, the largest of its kind in Europe, can produce 2.5 million square meters of solar cells annually. At its opening in 2021, Fili predicted that Exeger’s technology would “touch the lives of a billion people by 2030.”

Powerfoyle cells are already incorporated into seven products, including headphones, wireless speakers, and bike helmets, with six more announced. Companies like Adidas, Philips, and 3M are customers, and Exeger is rumored to be in talks with Logitech and Apple.

A Battery-Free Future

Exeger is among several startups commercializing indoor solar panels, drawn by the allure of clean, endless power. US-based Ambient Photonics entered the field inspired by the potential of smart homes and the goal of eliminating disposable batteries.

“The deployment scale of smart electronics has been limited by battery life and the use of traditional batteries, which require continuous charging, stagnate product design, and have negative environmental consequences,” says Bates Marshall, co-founder and CEO of Ambient Photonics. TV remotes alone contribute to 3.1 billion disposable batteries being discarded annually. Samsung aims to replace alkaline batteries with photovoltaic energy, potentially reducing greenhouse gas emissions by 6,000 tons per year.

“Every advancement in our product’s power density brings us closer to significantly reducing, if not eliminating, the need for disposable batteries,” Marshall adds.

Ambient Photonics’ DSSCs have been integrated into remote controls, though current technology limits them to indoor applications due to heat and light constraints. Exeger’s versatile and durable Powerfoyle cells, however, can potentially power a broader range of devices, significantly boosting battery life for energy-intensive gadgets like laptops and smartphones. They are also exploring a solar-powered tablet cover that might eliminate the need for frequent charging.

“Our grandchildren will laugh that we used cables,” Fili predicts.

Users of Powerfoyle products have become more aware of their light environment. “We are making people light conscious because light is power,” Fili notes.

Driven by the belief that Powerfoyle is an era-defining technology, Exeger has commercialized it at an unprecedented scale. Fili’s vision of a world powered by ubiquitous, flexible solar cells is ambitious, with Forbes likening his impact to that of Jeff Bezos, Bill Gates, and Elon Musk.

The technology behind Exeger’s solar cells remains a closely guarded secret. The specific use of the thousands of Powerfoyles produced each minute is also undisclosed, though their elongated shape suggests a common everyday product, possibly a keyboard. “This is really, really huge,” Fili says. “We’ve just secured a contract with the world’s largest supplier of keyboards and mice and partnered with some of the biggest companies on the planet. This technology is going to take over the world.”