Pinson Cycloturbine Photos

The Pinson Cycloturbine was developed by Herman Drees, one of American wind energy’s pioneers in the 1970s. He was one of the hardy band of small inventors who developed a slew of wind turbine models between the first and second oil embargo.

Drees was a Dutch national who I believe studied at MIT. The name Pinson I believe was derived from his American wife’s family firm. This was long ago and by the early 1980s Drees had moved on to other ventures.

Drees market his giromill as a Cycloturbine and used a cam-actuated linkage connected to a wind vane.

From the records I could find, he had two models. One was 12 feet (3.7 meters) in diameter and rated at 2 kW. The other was 15 feet (4.6 meters) in diameter with articulating blades 8 feet (2.4 meters) in length. The latter turbine swept 11 square meters and at a standard power rating of 200 W/m2 would be rated at 2.2 kW. As with most Vertical Axis Wind Turbines this model was overrated.

In the photos below, I can identify two of the sites. One is at Rockwell International’s Rocky Flats small wind turbine test center. The other is at New Mexico State University in Las Cruces. The location of the third photo is lost in time.

In the Rocky Flats photos you can see the unusual twin tail vane for controlling the cam linkage that governs the blades angle of attack. In the other photos the single tail vane is seen clearly.

Drees and Pinson apparently won a contract to develop a 1 kW version for what was to become the Department of Energy.

I first encountered Drees at the inaugural conference of the American Wind Energy Association in the late 1970s. In his presentation to the conference Drees described the challenges he faced, including–to my horror—climbing a tower with the turbine’s generator slung over his shoulder.

During the late 1980s or early 1990s, Drees became the site manager for a fleet of NedWind 500 kW turbines in the San Gorgonio Pass near Palm Springs. The Dutch turbines were unusual in that they used two blades not the three that even by then had become the norm. As of 2010, the NedWind turbines were still in operation.

ASI/Pinson 1-kilowatt high-reliability wind-system development: Phase I. Design and analysis