In 1954, Bell Labs scientists Daryl Chapin, Calvin Fuller and Gerald Pearson unveiled a solar battery that helped advance solar-powered technology

On April 25, 1954, a small group of scientists at Murray Hill, New Jersey, unveiled their newest creation: a modest windmill powered by a flashlight. There was no fanfare, venture capital, or keynote speech, just a brief demonstration of what Bell Telephone Laboratories dubbed a “solar battery,” a device that would go on to power handheld calculators and the solar panels aboard NASA’s Mars rovers.

A fix for dial tones, not for climate change

According to a 2024 review paper titled “The 70th anniversary of the Bell Telephone Laboratories ‘Solar Battery’ discovery,” published in the journal Solar Compass to mark the invention’s 70th anniversary, the device was created by engineer Daryl Chapin, chemist Calvin Fuller, and physicist Gerald Pearson. The issue the device solved was not climate-related; it was simply about the cost of maintaining telephone equipment for the Bell System. Chapin had been experimenting with selenium but switched to using silicon. Fuller, however, worked out how to spread boron throughout silicon wafers to create the p-n junction needed for photons to release electrons efficiently. The result was a solar cell that converted around 6% of solar energy into usable electricity, a low figure by modern standards but still six times more efficient than prior technologies, per Chapin’s profile on the National Inventors Hall of Fame. The New York Times reported on the invention the following day, describing it as the start of “the harnessing of the almost limitless energy of the sun for uses of civilization.” It was an ambitious claim for a newspaper to make, and it proved accurate.


From a 32-watt panel to a 250-gigawatt grid

This initial solar module produced only about 32 watts of power, roughly enough to light a couple of household bulbs, not nearly enough to run a hairdryer, and was installed on a telephone pole in Americus, Georgia. For the next couple of decades, solar remained a niche technology. It could be used in satellites and calculators but was just too expensive. The United States is now experiencing the fastest growth in solar power on record.

In 2026, developers are on track to add 86 gigawatts of new utility-scale generation capacity to the United States grid, the U.S. Energy Information Administration’s February 2026 capacity report shows. This is the highest amount ever recorded, with solar accounting for 51% of the total: a figure that would have seemed like science fiction to Chapin, Fuller, and Pearson, who were working on cells only a few centimetres wide.

What you could be annoyed about

It is worth noting that the technology, which could have begun to scale during the Eisenhower era, remained a niche application throughout much of the 20th century. Fossil fuels were still cheap, and there were few incentives for using solar. As a result, the silicon solar cell sat largely unused for roughly 50 years before its full potential was realized.

None of this is meant to diminish the achievement of Chapin, Fuller, and Pearson, who accomplished exactly what they set out to do. It simply shows that inventions can take a long time to be implemented. The solar battery was not a failure in 1954, its promise simply went unrealized for decades. From pocket calculators to the solar panels powering NASA’s Mars rovers, the technology that began with a toy windmill and a flashlight in New Jersey has since become central to how the United States generates electricity.