Low Speed Winds and the Advantages of Variable Pitch Turbine Blades

Most of us don’t pay much attention to lower wind speeds as a source of energy.  But, we, as a manufacturer of small wind turbines have focussed on the advantages of variable pitch wind turbine blades in capturing lower speed winds. The chief advantage of widening the operating wind speed range downward is to include these low speed winds, an abundant form of energy, previously underestimated.  However, variable pitch control also enables extending the capture range upward to include high speed winds (normally unsafe territory for fixed pitch turbines). In  short, we’ve taken a good wind turbine and made it better.  The result is our EXTRACTOR turbine.  Below we present some up-to-the-minute viewpoints and background on these topics.

As background, the following is a list of the historical development problems associated with high speed wind turbine operation:

• high speed winds were considered the only effective energy source
• high speed design and performance were exclusively pursued
• the advantages of low speed wind turbine performance were largely ignored
• stall (fixed pitch) control was the prevalent method of speed control
• the compromise was less efficient energy capture at high wind speeds
• high wind sites were invariably remote
• long transmission lines compromised remote site effectiveness

Learning from historical development problems, wind turbine manufacturers are building new turbines to accommodate a wider range of operating speeds.  Variable pitch operation is the secret and has now become virtually the universal choice for new large wind turbines. The same principles and advantages apply to smaller turbines.

The following  list of advantages have evolved from targeting lower speed winds:

• lower speed winds are now appreciated as more abundant and closer the user
• the latest variable pitch blade control offers superior lower speed operation
• the same control design  extends operating range right up to high wind speeds
• variable pitch blade control is now the most cost effective control method
• variable pitch operation also offers superior control flexibility
• new switching power conversion methods are now highly cost effective

Based on the above insights, we have designed our turbine to bring the benefits of variable pitch blade control right down to you as an individual household. Our EXTRACTOR variable pitch wind turbine is a proven winner in low speed wind energy capture and, by virtue of variable pitch blades, also provides continuous and safe power even in high speed winds.

Have the satisfaction of extracting your own renewable energy at unsurpassed low cost, simplicity, and minimum level of effort. There is no better way than starting with the best.