According to Tucson, the Life and Times of An American City (pages 108-110, opens a new window) by C.L. Sonnichsen, both electricity and gaslights appeared in 1882. However, the attempt to provide Tucson with electricity in 1882 failed within two years. Al Johnson, owner of an ice plant, attempted to provide the town with electricity via a ‘steam-driven, direct-current Edison bipolar unit.’ Johnson was not able to turn a profit and the company failed. The first successful electric company was organized in 1895.
Offering a somewhat different timeline, an August 1988 issue of Arizona Highways article says: "Tucson became the first Arizona city blessed with artificial lighting—not from electricity but from manufactured gas—in the spring of 1882. Three years later however the Old Pueblo's 600 residents were cast into the dark when the gas company failed and was sold at a sheriff's sale. The city lights did not come on again until 1892, this time thanks to electricity generated by steam turbine."
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