Forum Discussion
6 Replies
- Can't you mount that on the roof and it will charge the battery whilst you go down the road? Boy you guys are a real buzz kill! lol :B
- Some good physics in the reply.. The only way I know of to improve the effiency is to improve the efficiency of the mechanical to electrical converter (Generator/alternator).
Thomas Edison spent years working on this and.. .Well, improvements since his time have been very tiny indeed. He did not leave a lot of room for improvement. - There's all kinds of trade-offs with small wind, not the least being site considerations. This is where a VAWT may be a better choice. It certainly won't produce as much power as conventional HAWT if similar sized, but it will keep neighbors and the local regulatory bodies happier.
Another trade-off between VAWT and HAWT is that wind speed increases quite a bit with height. What you can get at 30' maybe almost double what you can get at 10'. I have a mast that is about 15' above grade. I'm not doing it as an option for house power and like to keep the neighbors happy, otherwise I would have a larger prop set and increase the height to 30+ ft..
There are a lot of myths about wind power and there is always someone trying to build a better mousetrap, mostly to counter the myths. Maybe we'll get advancements in material sciences in the future that will enable use of lighter wind capturing devices. That will open the door to homeowners that live in windy areas and make wind power less of a hassle and more of a bonus. westend wrote:
I'm sorry but more than half of that is a total crock. These "new" ideas about small wind generation continually surface.
It has been known for a long time that the amount of power harvested from wind is directly proportional to the swept area of the blades. Yes, funneling the air increases the flow speed but is not significant as reference to the size of the blades.
The part about less harmful to birds and less noise is pure hogwash. I have a 7' propset and you can't hear the blades standing next to the mast. It is all about how the air interacts or spills off the edge of the blade. I have stiff aluminum blades that are formed similar to an aircraft prop but with more fairing to the tip. This allows the air to spill off the edges with less turbulence, hence, less noise than a plastic blade that oscillates or a wood prop that is not faired as well.
The only bird I've killed is the buzzard disguised as a utility company.:B
I tend to agree with most of these points. Sweep area will define the limit of maximum power. The "Tunnel" that the air must pass through will limit the power output, and also limit the energy you can collect.
I would be more interested in vertical axis generators, with blades that are up and down, and rotate on the tower axis, and would have less side thrust while operating. One of their advantages is the vertical axis does not need to be mounted nearly as high in the air, above the other nearby obstructions. And they will start producing power in the 10 MPH range, with full power around 25 MPH.
Fred.- I'm sorry but more than half of that is a total crock. These "new" ideas about small wind generation continually surface.
It has been known for a long time that the amount of power harvested from wind is directly proportional to the swept area of the blades. Yes, funneling the air increases the flow speed but is not significant as reference to the size of the blades.
The part about less harmful to birds and less noise is pure hogwash. I have a 7' propset and you can't hear the blades standing next to the mast. It is all about how the air interacts or spills off the edge of the blade. I have stiff aluminum blades that are formed similar to an aircraft prop but with more fairing to the tip. This allows the air to spill off the edges with less turbulence, hence, less noise than a plastic blade that oscillates or a wood prop that is not faired as well.
The only bird I've killed is the buzzard disguised as a utility company.:B - Moved from DIY
