The Cleveland, Ohio Cedar Avenue substation was constructed in 1917, and was the first automatic substation completed for the Cleveland Railway Company. It was across the street from the Cedar Avenue power plant, which was then at the time the largest non-condensing direct-current plant in the United States, and was operated non-condensing because the exhaust steam was sold to a salt company adjacent at a price that made it difficult for the central station companies in Cleveland to compete with the Cleveland Railway’s power house on a per-kilowatt-hour output.
It was later decided that the cost to upgrade the Cedar Avenue power plant was prohibitively expensive. The production value at the Cedar Avenue facility was $1,265,565, and this, deducting the salvage of machinery and equipment estimated at $115,565, could be paid off at a rate of $20,000 per month. The cost of outsourcing electric production to the Cleveland Electric Illuminating Company was less than 6 mills per kilowatt. The cost of energy production in the Cedar Avenue plant was about one cent per kilowatt.
The new Cedar Avenue substation featured eight rotaries, each 1,500-kw in capacity with 60-cycle 514-RPM Westinghouse machines. With the installation, the railway company boasted 20 rotaries of 1,500-kilowatt capacity each and two 1,000-kilowatt-capacity, with controlling apparatus sourced from General Electric. The transformers were air-cooled Westinghouse 550-kilovolt-ampere., 11,000/410-volt single-phase units installed without shells.
The devision to use smaller capacity rotaries instead of four 3,000-kilowatt units came down to redundancy. If a serious overload was achieved and one of the units was subsequently disabled, an ever greater strain may have been imposed on the remaining units, A load of only 1,500-kilowatt, however, spread over seven units would overload each unit just slightly. There was determined to be little efficiency loss.
The exterior was finished with press brick in the front, with cut stone trim, with an interior and side walls of shale brick laid in cement motar. The interior also featured a tile finish. The roof was concrete supported on steel girders. After the exterior was finished, the interior electrical equipment, switchboards and so forth were installed in just five weeks.
On June 15, 1948, the Cedar Avenue streetcar line was replaced with a trackless trolley, which was then replaced with buses on April 12, 1963.