Publication: The Electrical Journal
Chicago, IL, United States
Transmission of Five Thousand Horse Power Over Fifteen Miles — Completion of a Great Commercial Achievement.
SACRAMENTO DRAWS THE EYES OF THE WORLD.
The Sacramento-Folsom transmission plant is practically completed, and will be giving light and power service in the City of Sacramento by June 22nd. This installation will go very far toward settling the question of transmission of energy by electricity, over long distances which we have been waiting for so long.
The distance between Folsom, on the American River, to Sacramento, over the route proposed, is about fifteen miles. The generators used, operate at 800 volts, to step up transformers at 11,000 volts. Under this pressure the current is conveyed over the route to the Sacramento plant where it is retransformed down to 125, 220, 500, 1,000 and 2.000 volts as may be required. The first machine sot in operation is a 1,000 horse power. General Electric, three phase alternating current generator, weighing thirty tons. When the plant is completed, there will be three other machines of the same character and size.
The plant is a model of civil, mechanical and electrical engineering. The dam is a massive structure of granite laid in Portland cement. It is 650 feet long, 80 feet high in the centre, Hi feet wide at the base. 20 feet wide in the crest, and contains about 48,500 cubic yards of solid masonry. It is provided with a heavy wooden shutter or dashboard six feet high which at high water is lowered into a recess in the crest of the dam. At low water this shutter is raised by hydraulic pistons, the depth of the basin is increased by six feet and additional storage capacity for the waste water provided. Normally the dam forms a storage basin or reservoir three and one-half miles long, and has a capacity of 18,000,000 cubic yards of water.
At each side of the dam are massive granite bulkheads and three head gates operated by hydraulic machinery, each head gate being 16 feet wide. The West Hide canal is 40 feet wide at the top, 30 feet wide at the bottom, and six feet deep. It is intended principally for irrigation purposes.
The power house is situated at the extreme end of the canal where a fall of 55 feet is available at high water. It is on the west side of the town of Folsom, where an immense cut in solid rock has been made, about 60 feet deep, 100 feet wide, and 150 feet long, from which a channel 40 feet wide leads to the river.
The hydraulic apparatus consists of four pairs of wheels of the McCormick horizontal shaft turbine type, enclosed In steel cases, having steel inlet pipes, eight feet in diameter and double discharge tubes. By this arrangement in pairs, the end thrust is neutralized and sufficient power and speed is developed to allow of direct connection to the generators. Each pair of wheels has a capacity of 1,260 H. P. at 300 revolutions per minute. They embody all that is latest and most improved in hydraulic practice, and are of larger capacity than any hitherto constructed in this country with one exception. They are operated under a head of 55 feet. The hydraulic plant also includes two special horizontal wheels for the exciters. The water after having passed the turbines is discharged through tunnels under the power house into irrigation canals for distribution over the country south and east of Folsom. The wheels and generators are located on the first floor of the building power house sixteen feet above the level of the water in the tail race,