North Carolina History Digital Textbook Project

A technological tour of the Biltmore Estate

By Sue Clark McKendree

LEARN NC was a program of the University of North Carolina at Chapel Hill School of Education from 1997 – 2013. It provided lesson plans, professional development, and innovative web resources to support teachers, build community, and improve K-12 education in North Carolina. Learn NC is no longer supported by the School of Education – this is a historical archive of their website.

Interpreting the transformer room

Wires come through the wall from the Generator Room which originally carried the power from the Dynamo Room to the Transformer Room.

  • This room first was used to house a series of large Gould storage batteries, each of which had a storage capacity of 2,000 ampere-hours (one 100 watt light bulb uses approximately 1 ampere). These batteries stored the DC power for use in the House during the day. Point out the two sets of transformers. These transformers reduced the high voltage of the imported AC power to a level that could be used by the systems in the House. We do not know at what point the Gould storage batteries were removed.
    • The two transformers next to the door were manufactured by General Electric of Schenectady, NY. They are “Type H, 60 Cycle Form A 110 KW transformers with a 2000 — 9000 primary and 220 - 440 secondary volt capacity.” The latest patent date on these transformers is July 9, 1901.
    • Adjacent are three older GE “#3 Type AB 60 cycle higher power batteries, with a 2100 - 10,500 primary and 375 secondary volt capacity. Their latest patent date was October 19, 1897. We do not know why they were so much more powerful than the later-model transformers, since modern AC electrical systems have 110/220 volt capacities).
    • Inside the transformers are copper conducting coils that circulated the current through the oil-filled tanks. The oil cooled the coils and reduced the power to a level where it could be used to generate DC current and to power the AC water heaters.
    • The primary volt capacity noted on the transformers represents the maximum voltage that could feed in, while the secondary volt capacity represents the stepped-down, or reduced voltage that we believe could then be used by the generator.
    • The wooden scaffold-like apparatus opposite the transformers appears to be original. We do not at this time understand the function of the switches mounted on it, although they appear to have been connected to the original wiring coming from the Dynamo Room. Perhaps they controlled the flow of current between the transformers and the dynamo or switchboard.
    • The iron apparatus above the switches reads “100 amps 7500 volts.” It has an oil level gauge and would appear to be some kind of transformer. Again, we do not know what its original purpose was, but hope to find out as research continues.
  • The floor was coated with a non-conductive material that would have readily absorbed any acid accidentally spilled from the original wet-cell lead acid Gould batteries. Note the indentations in the floor; the material must have been very soft at the turn of the century.
  • The motor on the floor in the center of the room operated an exhaust fan used to cool the transformers, which would have generated a great deal of heat. It was manufactured by the Buffalo Forge Company, “Heating & Ventilation Engineers,” Buffalo, NY. Note the opening in the back that pulled in hot air. During the summer this hot air was vented to the outside via the large insulated duct. Note that the duct also allows the hot air to flow in the opposite direction. In the winter, the damper visible near the window was closed, and the hot air was forced back into the House’s heating system, thus providing supplemental heat! (The duct is similar to the one used for the organ blower, which, in itself, is an advanced technological feature of the House.)
  • Mounted on the concrete platform under the windows were a series of transformers that probably were installed in the 1930s to reduce the voltage of imported power. These can be seen in the back of the room.

This is the end of the Technology Tour.

Implications of technological systems

Biltmore House incorporated the most technologically advanced systems available at the turn of the century. They are a reflection both of George Vanderbilt’s progressive interests and architect Richard Morris Hunt’s genius and attention to the most complex details of design and construction.

Although the mechanisms for the advanced technologies found in Biltmore House
were generally well-hidden from the Vanderbilts and their guests, they were absolutely necessary for their comfort and well-being. Biltmore House functioned in many ways like a luxurious hotel, and the technological amenities supported its operations.

These advanced technologies also lightened the workload of Biltmore House servants and made their lives more comfortable. Nearly two-thirds of the staff were native North Carolinians and most came from mountain cabins or farmhouses where such things as electricity and indoor plumbing were unheard of. To work and live in such a technologically advanced house surely must have felt like a privilege to many of the people who came here.

  • Perhaps leave your students with some these questions to ponder: We know that George Vanderbilt wanted the House to feature the most advanced technologies available. What if he had not died unexpectedly in 1914 at the age of 51? Suppose he had lived to be 90? What technological changes and improvements might he have made to the House if he had continued to live here into the 1950s? How might the House be different?
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