Every six seconds, a top-secret printer in a factory on the northern outskirts of Stockholm produces sheets worth thousands of euros each. Each one contains 108 miniature solar cells that will soon find their way into everyday gadgets – from keyboards to headphones – fundamentally changing the way we interact with technology. According to their creator, they will even force us to reconsider our relationship with light.
Sweden may seem an unlikely location for a solar revolution, but the lack of light during the winter months was one of the reasons for Giovanni Fili, co-founder of Exeger, to look beyond the sun as the sole energy source for a photovoltaic cell. His company’s groundbreaking technology can harvest electricity from virtually any light source, from direct sunlight to candlelight. It can even generate a charge from moonlight, although it would be a while before it would be of much use.
“Just like the algae at the bottom of the ocean, where it is almost pitch black, we can use very few photons efficiently,” says Fili. The independent. The T-shirt he wears describes his company’s technology as “world-changing,” capable of simultaneously addressing global energy needs and some of our planet’s biggest environmental challenges.
Indoor solar panels have been around for decades. Solar-powered calculators were first introduced in the 1970s, but the limitations of the amorphous silicon cells they rely on make them too low-powered, too fragile and too rigid to be integrated into other products.
The latest innovation stems from a 1988 discovery involving dye-sensitized solar cells (DSSC). A pair of scientists at UC Berkeley in California invented a cheap, high-efficiency cell that was both semi-flexible and semi-transparent, providing a path to commercial development of the technology.
Just over twenty years later, Fili and Exeger co-founder Henrik Lindström came up with a new electrode material that offered a thousand times better conductivity. The breakthrough formed the basis of their Powerfoyle cells which are now produced on a commercial scale.
Exeger’s Powerfoyle solar cells are a radical departure from traditional glass-covered panels, eliminating the silver lines you see on them that serve as conductors. They are also not sensitive to partial shade, which drastically reduces the efficiency of photovoltaic panels.
The patented skin-like material can even transform into virtually any material, allowing seamless integration into a wide range of products while remaining water, dust and shock resistant.
“It works in all lighting conditions, 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 is also beautiful,” says Fili. “This way we can integrate into products that are already sold in billions of units per year.”
Exeger’s factory in Stockholm has the capacity to produce 2.5 million square meters of solar cells annually, making it the largest factory of its kind in Europe. Speaking at the plant’s opening in 2021, Fili predicted that Exeger’s technology “will impact the lives of a billion people by 2030”
The Powerfoyle solar cells have already made their way into seven off-the-shelf products – including headphones, wireless speakers and a bicycle helmet – while a further six have been announced. Customers include Adidas, Phillips and 3M, while they are also rumored to be in talks with LogiTech and Apple.
A battery-free future
Exeger is one of many startups pioneering the commercialization of indoor solar panels, with the promise of clean, endless power attracting researchers and entrepreneurs alike.
US-based Ambient Photonics was drawn into the space by the ‘magical’ potential of the smart home, as well as the hope that it would be possible to eliminate the need for disposable batteries.
“The scale at which smart electronics can be deployed is limited by battery life and the use of traditional batteries, which require continuous charging, stagnate product design and have negative environmental impacts,” said Bates Marshall, co-founder and CEO of Environmental photonics, narrated The independent.
Television remote controls alone are responsible for throwing away 3.1 billion disposable batteries every year Samsung estimates. The Korean electronics giant has made the switch from alkaline batteries to photovoltaics a priority to achieve its sustainability goals, claiming it could reduce greenhouse gas emissions by around 6,000 tonnes per year.
“Every advance in the power density of our product brings us closer to a future where the need for disposable batteries is significantly reduced, if not completely overcome,” says Marshall.
Ambient Photonics’ DSSCs have so far been integrated into remote controls, although limitations on the amount of heat and light they can be exposed to mean the technology is currently limited to indoor applications.
The versatility and durability of Exerger’s Powerfoyle means its only limitations are power-intensive devices such as laptops and smartphones – although they could significantly increase battery life by 50-100 percent. Exeger is also exploring a solar-powered tablet case that could provide enough power for infrequent users so they never need to charge.
“Our grandchildren will laugh because we had cables,” says Fili.
One trend Fili has noticed is that users of Powerfoyle products have become much more aware of their surroundings and the presence of light in their lives. “We make people light aware,” he says, “because light is power.”
Fili is driven by the belief that the Powerfoyle is an era-defining technology. Exeger is the first to commercialize the technology on this scale, although it is still relatively nascent as Fili considers everyone on the planet a potential user. Others seem to have confidence in his claims Forbes He compares him to figures such as Jeff Bezos, Bill Gates and Elon Musk.
The technology behind Exeger’s solar cells, like the printers that produce them, is a closely guarded secret. Even the purpose of the thousands of Powerfoyles currently being printed every minute at the Stockholm factory is not yet widely known. (Their elongated shape strongly suggests that they will be used in a product that most of us use every day – a product on which this article is being typed.)
“This is really huge,” says Fili. “We just signed a contract with the world’s largest supplier of keyboards and mice, and have already partnered with some of the largest companies and brands in the world. This technology is going to take over the world.”