Many people know that the solar cell was invented at Bell Labs, helped along by the men who created the silicon semiconductors that underpin electronics. But a far less well-known story today is the nearly simultaneous creation of what were known as “atomic batteries” by Bell Labs’ arch-rival, RCA, in 1954. As described in John Perlin’s From Space to Earth, the battery was made from silicon like a solar cell but, “it used photons emitted from strontium-90, one of hte deadliest residues of radioactive waste, to force the flow of electrons and positive charges” that drove the electricity.
RCA’s founder and president, David Sarnoff showed off the battery at a press event at Radio City, tapping out “Atoms for Peace” on an old-school telegraph powered by the battery in a darkened room. The press ate up the presentation, with The New York Times saying, “even now it ought to be possible to make a tiny wrist watch which would be driven by electrons and which would run for twenty years.” Waldemar Kaempffert, the reporter on the scene, even hinted that radioactive waste “will have important industrial uses, now that a way has been found to generate a current with strontium-90.”
If it was safe (ahem), this member of the press agrees: Atomic gadgets are cool — and this one had found a way to transform radioactive decay directly into electric current using a silicon cell. Why not power your watch with nuclear waste?
Well, it turns out that atomic batteries are weak sauce. The RCA “atomic cell” only delivered one-millionth of a watt. Bell’s Solar Battery — the earliest remotely efficient solar cell — presented in April of 1954, “delivered fifty million times more more power than the RCA device,” Electrical World noted.
Perlin also reveals that the silicon cell powered by strontium-90 would have worked just as well, if not better, if it had just been exposed to light. The strontium-90 was hardly doing much at all, but it was useful for the Cold War aim of the United States: promoting the peaceful uses of nuclear energy — Atoms for Peace, as seen in the video — so we could build weapons without seeming like overbearing goons. The strontium-powered cell allowed the naturally futuristic minds of the public to imagine that radioactive waste would eventually be put to good use, not just end up a big mess. The director of RCA Laboratories grasped that, telling his scientists, “Who cares about solar energy? Look, what we really have is this radioactive waste converter.”
Still, five years later, we find Time writing up the SNAP III, a later “atomic gadget”:
On President Eisenhower’s desk stood a domed metal gadget about half the size of a derby hat. Current flowing from it spun a small propeller. Named SNAP III (for System for Nuclear Auxiliary Power), the little gadget is an atomic battery small and light enough to go into a satellite and keep its instruments and radio voice going at least ten times as long as any chemical battery that the Russians or the U.S. have yet employed.
The Snap III produced a measly 2.7 watts. Of course, the batteries were terrible, so they made the cell look decent. A better comparison would have been solar cells. Both batteries and solar cells were put into the Vanguard I satellite. The batteries lasted 19 days, the solar cells made it seven years. That’s 134 better performance, and a hell of a lot better than the 10x improvement offered by the SNAP III. Yet there’s no mention of solar cells in the Time article.
Not that the lack of press hurt photovoltatic development for space applications. Solar cells ultimately proved far more economical for satellites and continue to power modern day communications satellites.
