1976 · Solar-Charged Calculator · Work 949 of 1,871
The wooden sill of an office window in Osaka on a clear December morning, a flat pocket calculator eleven centimetres long lying face down in a shaft of low sunlight, its back of cream-white plastic with two rectangular windows, in each eight small grey-blue solar cell fields in two rows of four catching the light, a plain smooth cream area between them and two small screws, beside it its open case of brown grained leather with two cut-out windows for the cells, a white porcelain cup of green tea, half-raised slatted blinds casting thin stripes of shadow across the sill, the city soft and bright beyond the glass.
What it was used for
Sharp introduced the EL-8026 solar pocket calculator in 1976. According to Tedium the solar cells sat on the back, were large, and served to charge the built-in battery: "the solar cells were large, located on the back, and designed to recharge the battery". Sharp's own corporate blog describes the device as the world's first solar-powered calculator and says it allowed use without worrying about battery life.
What was new
Who came first depends on the definition. Tedium calls the 1976 EL-8026 the first solar calculator and, in the same text, calls the Teal Photon, whose advertisement appeared in Popular Science in August 1978, the machine "widely believed to be the first calculator that did not need a charger". In the Sharp the current passed through a rechargeable cell; in the Teal it came straight from the light. The barb: the cell on the back did not power the calculator but recharged its battery - the battery stayed in the machine.
What the sources leave open: The "world's first solar calculator" claim comes from Sharp's own blog. Tedium (Ernie Smith, 9 August 2017) supports it but places the Teal Photon beside it. Neither source gives the EL-8026's price, production figures or dimensions; vintagecalculators.com and datamath.org could not be retrieved in this run for technical reasons.