Pacwind's latest VAWT...

[skids]

Pacwind's got another design out the gate. They have PR out saying it's now "available" which means probably that it will be in a few months since they only sell through redistributors. I thought the SeaHawk was nicer from an avian perspective, but it was too pricey for the power it put out, though a better deal than many. We'll see if they manage to make the math more favorable with this model, which is targetted at operation in areas with lots of low speed wind rather than bursts of high speed wind.

The old Seahawk:


The new, now "available" Delta I:



The upcoming Delta II's power curve.



(all images from here, where there are more specs: http://www.pacwind.net/products.html)

PR piece: http://www.renewableenergyaccess.com/rea/news/story?id=47509

Incidentally, someone posted a link to the peswiki a while back, and though you really have to bring a salt shaker with you when you visit, it was good to see some news about TMA wind's product development work, since they don't seem to be up on their PR enough to update their own website:

http://pesn.com/2007/02/01/9500453_TMA_Wind_going_commercial/

[NNadir]

1. You should write to those folks building the big coal plant in the Everglades.

They think they need to use coal.

[Massacure]

2. The Delta I sure has one heck of a jump in power between 12 and 12 mph.

I wonder why that is.

Even if you could average 200 watts of power out of it though, it would make a pretty good dent in your energy bill, especially for something that is only four feet tall and eight feet wide.

[skids]

3. It's due to "lift"

The design uses drag to get going in low wind speed and shifts to aerodynamic lift thereafter. Lift only works past a particular windspeed (which depends on air density and pressure and various other factors, but is generally sticks around the same order of magnitude.) The trick to this particular design, I believe, is that the shift of blade orientation to do that is achieved simply by the bending of the blades due to centripetal force. Pretty sleek materials engineering there.