This station is designed for a capacity of 12,000 Kw., in eight 1500 Kw. turbine-generator units. It furnishes current for motor driving and general testing in the Works and is also a reserve for the Schenectady lighting plant and railway system which it supplies through the Dock Street Sub-Station. Three-phase transmission at 10,000 volts is used, as most readily applicable to these conditions. The station has been designed to produce power at minimum cost under the widely varying demand set by the conditions, and is in every way a good demonstration of the capabilities of the Curtis turbine applied to electric power generation. The following units have been installed: A 1500 Kw. turbine for permanent service in the plant, a 2000 Kw. and a 500 Kw. unit for expcrimental purposes.
[Photo: New Power Station: original size (19K) | 4x enlarged (70K)]
The building is 200 feet long and 80 feet high, and is divided by a lengthwise partition into two main rooms. The boiler room is 80 feet wide and is equipped with eighteen 513 H.P. water tube boilers, each comprising three groups of tubes of which one constitutes a superheater capable of giving 200 degrees of superheat. They are fed with clean, soft, oil-free water from the turbine overflow. There are two 200-foot brick stacks, and forced draft is provided for bringing up the fires quickly. Automatic stokers of the underfeed type are used, and labor and attention in the boiler room are further reduced by the use of motor driven coal and ash handling machinery.
The main steam gate valves are also operated by small electric motors.
[Engraving: High Potential Oil Switch: original size (9K) | 9x enlarged (56K)]
The turbine room (50 x 200 feet) is spanned by a 50-ton crane and contains, without crowding, the above turbine-generator equipment and auxiliary machinery, such as condensers, electric driven air, circulating and water pumps. Mounted on a gallery overlooking the turbines are two 250 Kw. double commutator rotary converters for 250 volt, three-wire direct current distribution, and the switchboard for the whole plant. The Form H high tension oil switches are of the same type used by the Metropolitan and Manhattan Railway Companies, the New York Gas, Light, Heat, and Power Company, the New York Edison Company, the Niagara Falls Power Company, etc. They are mounted in fireproof switch cells, operated by small direct current motors, and automatically controlled by overload and time limit relays.
There are two sets of high tension and low tension busses, subdivided by sectionalizing switches to be used simultaneously as required. All alternating current instruments and apparatus are energized by low tension obtained through current and potential transformers.