Blades For Low Wind Speeds
To turn wind generators at lower wind speeds, you need more surface area. You can efficiently convert low wind speeds into charging voltage if you use multiple blades. When you increase the surface area, you increase the drag at higher speeds, but you'll have a lower start up speed. Multi blade designs benefit low wind speed areas. Blade width also plays a role in surface area, but should only be used in very low wind speed areas. Also consider using a VAWT. Either way you want a low start up speed and 13 volts as soon as possible. The most common low wind speed design is a six bladed wind generator.
The Most Efficient Generator Design
Permanent magnet generators are the most efficient electricity generators. If you want to see a hybrid wind generator look at Honeywell's new design called Windtronics. This design uses many blades and turns a permanent magnet generator inside out. The magnets are on the tips of the blades and the stator is on the outside of the generator. Windtronics claims start up speeds at 4mph, and the system furls at 45 mph winds. The output is 2,000 Kw per year for a cost of ,500. You can build your own hybrid six bladed design for less than 0, and achieve the same output.
Using a Digital Guide Versus Buying Commercial
Digital guides can show you how to build a high efficiency wind generator. These guides cost from to and are generally a good investment. They take more work, but your return on investment for renewable energy is much quicker. On average a commercial system can take 25 years to recoup the initial investment, while a self built system can be recouped within months.
