The Ground as an AWES Hub
Many of our best
AWES ideas emerged early, but take years to understand in the simplest
most direct way. The "GroundHub" POV below is a typical case. Once we do
see clearly, the leap in progress is exciting.
Many AWES schemes involve kites going around a carousel, circular track,
or cableway. These can be seen as true turbines, in the sense that the
ground surface itself becomes a megascale hub structure. This sort AWES "groundhub"
has the golden advantage of megascalability, with no added mass aloft.
Large hubs also favor direct generation of electricity by high-speed
motion, by impinging the generator load at the rim*.
The problem is, this is a vertical axis hub, and we know that an ideal
windpower axis is oriented along the wind direction like a HAWT. We have
at several solutions at hand. The most common and trickiest idea is to fly
kites along the circle in complex orbits, with phases for power and
recovery of upwind distance. KiteLab developed Whipple-Tree approach with
lines and pulleys to allow the tilting of the entire circle of kites to
better face the wind, as a sort of autogyro. Its been shown that circling
kites can be cross-linked by lines to integrate them, for reduced mishaps
and control requirement. A kite arch spanned over a kite-turbine, or even
an array of them, can allow kite turbine operation square to the wind.
A major variant is a generating ground-hub much like a classic rotary
engine, but driven by radiating pumped lines from adjoining kite fields.
All kinds of kite-pumping schemes (rotary or oscillating) can feed-in
power in-phase. This maximizes the ground structure portion and minimizes
need for steel and concrete structure. Land and airspace efficiency can
also be maximized. Kite farms like this may be an optimal gigascale AWES
configuration for true utility-scale generation.
~Dave Santos Nov.
* To answer a recent Forum question- Impinging a load on a wheel rim is
mechanically practical and efficient (gear principle). Powered land
vehicles operate nicely by this principle. Ground hub ideas scale the
wheel to unprecedented sizes, with impinged generators easily brought to
Comment and development of this topic will be occurring here.
All, send notes, drawings, links, and photographs!
- Terms and aspects:
- Related links and concepts:
- Earth as hub of closed-loop WECS
- Commentary is welcome:
- Partial prior art on closed-loop-on-ground WECS