Redlands Power Plant 1893

FEATURES of this Power Generation Site:

Notable features: First commercial Alternating Current 3-phase hydro power plant

Frequency: 50 cycle
Three-Phase, Alternating Current
Power Transmission Length: 7 miles
Power system built by: General Electric
Notable Engineers: Elihu Thomson, William Stanley, Almirian Decker, Dr. Louis Bell (chief transmission engineer), Edwin Wilbur Rice Jr., Ernst Danielson
Maximum Power Output: 250 kW

Hydro-electric background

Water power had been used for thousands of years, but use for electricity began in the mid 19th century. The early power plants like the one in Dolgeville, NY (1879) ran DC power for industrial uses very close to the dam. Until the 3-phase AC generator, there was no way to transmit power long distance (to downtown areas in cities for example).

Redlands, North Americas First:

The Germans had proven at the Lauffen-Frankfurt demonstration in 1891 that 3-phase AC power could be sent 109 miles. Westinghouse and General Electric studied the event and immedicately began working on 3 phase systems of their own. Elihu Thomson at General Electric had been working with AC power since 1885, and set to work on the Redlands plant as a first commercial installation. The San Bernadino area had already been using DC power to move water for agriculture and human uses. In 1891 work began to get an AC power plant in the area to sent power to nearby Redlands, a feat not possible with the conventional DC power houses.

Why Redlands?

By the late 1880's the agricultural business had expanded in southern California. Valley areas with natural streams were fully utilized by the orange growers. There was a great quantity of land in the surrounding hills which could potentially be used for cultivation if there was a way to pump water uphill. Eastern investors supported the move to build the Redlands powerhouse which used the power of the Mill Creek. Pipes were placed under the creekbed to channel almost all the water into the Pelton waterwheels. The generators are pictured below. Almirian Decker designed the plant as a whole while Thomson worked the technical details. Dr. Louis Bell represented the Thomson-Houston Company(part of General Electric) on the west coast and pioneered early distance transmission systems. Ernst Danielson, a talented Swedish engineer helped work on the project and then moved on to build 3 phase power plants in Sweden. Dr. Louis Bell went on to work on the Folsom, CA power plant.

If you wish to read in detail about this plant, please read this work by Ronald L. Burgess

There were two three-phase hydroelectric generators rated at 250-kw, 2400 volts, each.

The power was transmitted seven miles to the town of Redlands using wooden power poles. The year after completion there was a drought. Today the Mill Creek is mostly piped underground, with a small stream on the surface (see photo below)