new version of dual vertical axis turbine

[plasmadust]

This is the latest version of the dual vertical axis turbine we are building.
This new unit is half the height of the last one, and thanks to the new axial flux generators, it produces as much as the previous version.
We were already 48% efficient with the 8 ft unit, and were recognized by DOE as such.
We build these right here in Texas.
This unit starts rotating at 3mph and produces at 6mph. The top speed is 175 rpm for 3.5kw, and that is in 12-14mph wind.
We used the larger unit at Earthday Texas last year on our EV charging station with 20kW of battery storage. We had 56 Tesla's parked around us there.
We plan on going to 8-10kW on the larger unit with larger axial flux generators.
Efficiency should be way above 50% on both units.
BTW, there is next to no noise from the blades <30db

 

[plasmadust]

I just posted about the wind charging station we built for Tesla at Earthday Texas. Figure I should post a picture of that as well.
If anyone is interested, That event is now the largest in the World and growing every year. Next year we will furnishing the chargers for the i8 at its premier at that event. Fairpark, in Dallas is where the event is held, and expect 100,000+ at the next event.
Anyway, here is what had there last year. Just noticed one of our electric police bikes in the picture as well. KHS frame, 48V, geared hub motor. Cops have been using them for 10 years now with no problems.

 

[friendly1uk]

I like it. Some time in a wind tunnel would be interesting. Or with a fire extinguisher and a flat bed truck.

 

[johnrobholmes]

contra rotating turbines, I hear it is great for efficiency. Looks like a pretty nice compact unit!


I will be flying down to DFW for a business meeting in the next few weeks, where are you located?

 

[adriftatsea]

This is really neat. I have a few questions:

- Is there an 'endless-sphere' equivalent for wind turbine discussions?
- What are the blades made of?
- Is the vertical load supported by bearings or teflon washer'ish things?
- What kind of fuss do you have to go through permit wise to build one?