Tuesday, December 11, 2007

VAWT : Vertical Axis Wind Turbine

After some costly experiments, I have concluded that a horizontal wind generator is all wrong for a civil defense application.

Here are just a few of the merits of a VAWT turbine:

Easy construction using just about anything. VAWTs can be build from plastic buckets, PVC, metal pipe, anything that is a cylinder that can be cut. The design is elegant, simple enough for any layman to understand in seconds and therefore easy to repair and replace when it becomes necessary. If the post apocalyptic world has any cylinders left in it, you should be able to build as many VAWTs as you need.

Tough enough to easily withstand conditions that would wreck a regular wind tower, even 300 mph winds. It is hardy enough to last through extreme conditions of all kinds with a longer life and lower maintenance requirements.

It is self damping in speed to avoid many of the problems associated with rotors in wind towers, meaning it is safer to operate and puts less stress on the structure which can be located closer to the ground. It has fewer moving parts to wear out, in any event. The only cost is a slightly reduced efficiency but the gain is very large.

Requires no vane to point it into the wind, which also means no slip rings! Trying to locate slip rings was one of the things that drove me to investigate VAWTs as an alternative. Slip rings are ridiculously expensive and therefore prohibitive in a system for which robustness is the primary requirement. The VAWT spins in any wind strong enough to turn it, irregardless of direction.

It can be protected from the elements, housed in a safety cage and sealed against ice, rain, moisture and grit that represents a serious degeneration over time for any instrument that relies on moving parts. It can be anchored more firmly and even camouflaged where a regular wind generator cannot be.

Check out the link to the plans and also have a search for "Savonius" wind generation. I think the alternate vertical designs may be more efficient but they are as fragile and vulnerable as the horizontal wind towers for a variety of reasons. The Savonius design looks like the way to go, although it may be optimal to have several vanes on the drum as opposed to two. I will have to do a bit more research.


Anonymous said...

VAWT turbines also work better in cases where the wind turbine in mounted on a building.

The biggest downside is that most home owners associations won't allow them. Fortunately, after doomsday, we can just shoot the bastards or watch laughing as those sheep flee to a FEMA shelter (slave camp) once their three day supply of food runs out.

Texas Arcane said...

Look on Youtube to see the improvised designs.

I saw one housed in a monolithic structure that looked like it would run steady during a cyclone. Definitely the only way to fly for a low maintenance aboveground shelter power station that has to run reliably for long periods without being serviced.

Better Red than Dead said...

That is one awesome link there Tex.

I'm very excited by the prospect of building one of these Turbines as a project. My flat does not get enough sun to run solar panels. This looks like it'd do the trick.

Thanks for that. Keep up the great work on this blog. And buy some more rice people....

Vertical Axis Wind Turbines said...

vertical axis wind turbines is that the horizontal wind turbines have a tail rudder that always moves to face the turbine into the wind. Depending on how the wind is blowing, this can be distracting or downright annoying.

Vertical axis wind turbines are stationary and can be anchored with guy wires. As for which type of turbine captures the wind better, there is debate there as well.

Vertical Wind Turbine said...

vertical wind turbine are both efficient and quiet, making them more suitable for energy production in residential areas than previous wind-based renewable energy technologies. Many current VAWT models resemble eggbeaters, with two blades attached to a central shaft, which is in turn anchored in a power generator. Others have a number of large, flat blades protruding from the central axis; and still others have a helix of extremely light plastic surrounding the axis. They typically stand between two and five feet in height and the best ones are able to attain 30 – 60% efficiency, depending on where they are located.