The Canadian fabricator, DAF-Indal, installed a second generation 50 kW Darrieus turbine in 1981 at the the Romero Overlook Visitor Center on a ridge above the San Luis Reservoir in California’s Pacheco Pass. The two-blade design evolved from work begun in the mid 1970s. A second unit was installed at Southern California Edison’s Devers Substation test site in 1982.[1]
An earlier version of the design was installed in 1979 for the US Department of Agriculture in Bushland, Texas in a wind-assisted irrigation application. See the photo below.
[1] Paul N. Vosburgh, Commercial Applications of Wind Power (New York : Van Nostrand Reinhold Co., 1983), http://archive.org/details/commercialapplic0000vosb, page 55-56, and 96.
