On 15 Oct, 23:23, "Dave Plowman (News)" wrote:
In article
,
* *Andy Dingley wrote:

On 14 Oct, 14:40, "Dave Plowman (News)" wrote:
Indeed. But buying number one of anything has its risks. I did wonder
about the super efficient gearbox. That would have applications for
anything - so smelt of hype.
Most vertical axis turbines (actually most domestic scale turbines,
either way) have a 100% efficient gearbox by simple virtue of not
needing one - just drive the generator directly. TNP seems to think
that a gearbox and model aircraft motor is the way to go, so what more
evidence do you need?
The turbine on Grand Designs looked like a Skyrota, the bunch out
Londonderry way.

I spent the whole weekend a couple ago in the middle of a wind farm in the
NE of Scotland. Was surprised just how slow they turned. Have those no
gearbox too?

--
*I speak fluent patriarchy but it's not my mother tongue

* * Dave Plowman * * * * * * * * London SW
* * * * * * * * * To e-mail, change noise into sound.

They do have a gearbox. Assuming they have synchronous generators,
they only have two speeds. Stop and go.
The torque generated varies with wind speed.
Most designs have variable pitch "propellors".