Jul
02Building a Home Made Wind Generator: How to Build the Blades
Posted By: Freddy on July 2, 2009 at 6:19 pmThis is a walk trough to build a blade for your home made wind generator.
Your choice of blade design and material greatly affects your home made wind generator’s overall efficiency and performance. Most modern factory produced wind energy blades feature a 3 blade design with very slender blades made from space age materials mostly. Three blades work best to avoid vibration.
Those slender blades catch every bit of wind energy coming by too. You would think that the blades would have to be large in order to do this. But the most important aspect of blade design is how big of a diameter they form.
You will need a blade with outside diameter, measured to the tips, of at least 8 feet in order to achieve about 1000 watts of power production. If you don’t feel comfortable with this big of a machine then scale it back accordingly. Read more…
A 3 blade design can capture up to 8 horsepower of energy while many of the old bladed design will have a hard time producing 2 horsepower! All those blades get in the way of the wind moving through the blades and actually slow down the spin. This is what we regard as turbine efficiency.
Thankfully, the new materials and new blade design are available for us to take advantage from. These modern designs feature a high tip- speed ratio.
What is Tip-Speed Ratio?
Simply put, this is a comparison between angular velocity of the tip of wind generator blade and the wind speed.
Tip-Speed Ratio = Tip Speed / Wind Speed
Most of the newer models available today have a tip speed ratio of between 5:1 and 8:1. That is really moving. In other words, modern blades can rotate faster at lower wind velocities. The larger the number, the better efficiency in capturing wind energy.
This compares to the old slow moving water pumping windmills that used to dot the landscape with a tip speed ratio of around 1:1.
The old style windmills were designed to pump water, and although less efficient, they provided higher torque (because of the large blade outside diameter) and better performance at low wind speeds which gave them a steadier pumping action (more water delivered) in low wind situations. They had to start pumping immediately so they had to catch the wind at the start very effectively.
Click on the Image For Detailed Instructions
If you think of your wind generator blades as aircraft propellers you will gain a new appreciation for the intricate designs necessary to achieve this high overall efficiency at tip speeds that approach 125 miles per hour.
You do not need to replicate these technical advances to have an efficient machine. Just follow the simple directions for a smooth operating homemade wind generator.
Note that the most efficient aircraft propeller design is not the best design for a wind generator blade. The propeller is designed to move air, while the wind generator blade is designed to be moved by the air. Subtle differences exist which we will explain further.
Although it is much less expensive to initially get hooked into the local electric company’s grid than it is to set up and hook into wind turbines, in the long run one saves money by utilizing the wind for home’s energy needs—while also becoming more independent.
Not receiving an electric bill while enjoying the advantages of the modern electrically-driven lifestyle is a wondrous feeling.
Electric bills and fuel bills are rising steadily—but the cost of running a wind turbine energy is zero, and the cost of installing and hooking up a turbine is steadily coming down as demand rises and more commercial success is realized by various companies producing the turbines and researching technologies to make them ever more efficient.
In addition, people are moving away from the traditional electric grids and the fossil fuels for personal reasons including desire for greater independence, the desire to live remotely or rurally without having to “go primitive”, political concerns such as fears of terrorist strikes on oil fields or power grids, or concerns about the environment.
Again, this motivation to get away from the traditional energy sources is the same one that causes people to seek the power of the wind for their home energy, giving more business opportunities to profit from wind turbine production and maintenance, which drives their costs down for the consumers.
In nearly thirty states at the time of this writing, homeowners who remain on the grid but who still choose to use wind energy (or other alternative forms) are eligible for rebates or tax breaks from the state governments that end up paying for as much as 50% of their total “green” energy systems’ costs.
In addition, there are 35 states at the time of this writing where these homeowners are allowed to sell their excess energy back to the power company under what are called “net metering laws”. The rates that they are being paid by the local power companies for this energy are standard retail rate. In other words, the homeowners are actually profiting from their own energy production.
Some federal lawmakers are pushing to get the federal government to mandate these tax breaks and other wind power incentives in all 50 states. Japan and Germany already have national incentive programs in place. However, “A lot of this is handled regionally by state law. There wouldn’t really be a role for the federal government,” as Craig Stevens from Energy Department says.
And, as might be imagined, there are power companies who feel that it’s unfair that they should have to pay retail rates to private individuals. “We should [only have to] pay you the wholesale rate for … your electricity,” according to Bruce Bowen, Pacific Gas & Electric’s director of regulatory policy. However, the companies seem to be more worried about losing short term profits than about the benefits, especially in the long run, of the increased use of wind turbines or wind farms.
Did you know that you can build your own wind generator for your home energy demand? Learn how. Click on the image:


