80th Anniversary of Smith-Putnam Turbine Going Online

By Paul Gipe

19 October marks 80 years since testing began of the 1.25 MW Smith-Putnam turbine on Grandpas’ Knob near Rutland, Vermont in 1941. To mark the occasion, the York County History Center in York, Pennsylvania is opening its digital exposition Tuesday, 19 October. The S. Morgan Smith Company, of Smith-Putnam fame, manufactured hydroelectric turbines in York, Pennsylvania before it ventured into wind energy.

In addition to the digital exposition, the History Center has scheduled a virtual presentation by Dr. Jim Manwell from the University of Massachusetts at Amherst for 28 October at 7.00 pm EDT on the history of the Smith-Putnam project. Manwell is an expert on the Smith-Putnam project. Registration for his presentation is required, but the presentation is free.

Dr. Manwell is one of the founding members of UMass’ Wind Energy Center and has an extensive collection of Smith-Putnam documents and correspondence. More on Dr. Manwell’s presentation can be found on the History Center’s web site.

The Smith-Putnam turbine was a giant for its day with a two-blade rotor spanning 175 feet (53 meters). It swept five to ten times more area of the wind than any other wind turbine developed during the war years.

The turbine was first driven by the wind on 29 August 1941 as part of its acceptance tests. It operated commercially for a few weeks in the spring of 1945. During this brief period the wind turbine generated 61,780 kWh in 143 hours of operation. Subsequently it threw a blade and was dismantled; bringing to a close an ambitious project that has left a lasting legacy among American wind engineers.

It was three decades before anyone anywhere in the world attempted a wind turbine of this size again.

More documentation on the Smith-Putnam project can be found at wind-works.org. The web site contains an extensive collection of Smith-Putnam Industrial Photos. There are also pages on

  • Film of Turbine Operating,
  • Patents & Patent Drawings,
  • Articles from the Period,
  • Who Was Carl Wilcox?,
  • Wind Tunnel Tests, and
  • Artifacts.