From what I remember, most problems with windmills are due to 2 factors:
Not enough wind
Too much wind
I believe the generating curve is exponential, in that it isn't worth generating below a certain wind speed, which most locations don't reach. Just a little drop in wind speed can more than halve your generating power. Added to that, turbulence makes steady wind speed attainable mainly at higher altitudes, therefore requiring elevation (high towers)
Once you do have good generating capacity, what do you do when the wind is over the maximum threshold? A lot of older / smaller windmills need to be stowed during high wind, as they just can't cope with the amount of power developed.
Putting the windmills on a kite could indeed manage these issues somewhat - I'd imagine similar to sailing - where you can generate more speed than the wind provides, and possibly free-wheeling to dissipate excess speed / power.
> From what I remember, most problems with windmills are due to 2 factors: Not enough wind Too much wind
That's very apt :)
> I believe the generating curve is exponential
It goes up with the cube of the windspeed
Most windmills nowadays (the grid connected ones anyways) are of the variable pitch type, which means they can run constant RPM up to a maximum windspeed at which they are shut down to avoid damage. Such high winds occur relatively infrequently though.
Freewheeling in a storm is not an option, a windmill that runs unloaded will quickly overspeed and fly apart.
Comments
From what I remember, most problems with windmills are due to 2 factors: Not enough wind Too much wind
I believe the generating curve is exponential, in that it isn't worth generating below a certain wind speed, which most locations don't reach. Just a little drop in wind speed can more than halve your generating power. Added to that, turbulence makes steady wind speed attainable mainly at higher altitudes, therefore requiring elevation (high towers)
Once you do have good generating capacity, what do you do when the wind is over the maximum threshold? A lot of older / smaller windmills need to be stowed during high wind, as they just can't cope with the amount of power developed.
Putting the windmills on a kite could indeed manage these issues somewhat - I'd imagine similar to sailing - where you can generate more speed than the wind provides, and possibly free-wheeling to dissipate excess speed / power.
Indeed an interesting area to watch!
> From what I remember, most problems with windmills are due to 2 factors: Not enough wind Too much wind
That's very apt :)
> I believe the generating curve is exponential
It goes up with the cube of the windspeed
Most windmills nowadays (the grid connected ones anyways) are of the variable pitch type, which means they can run constant RPM up to a maximum windspeed at which they are shut down to avoid damage. Such high winds occur relatively infrequently though.
Freewheeling in a storm is not an option, a windmill that runs unloaded will quickly overspeed and fly apart.