Average wind speed in Ireland is 3.12 - 8.04 m/s
The average wind speed in Ireland according to the Irish metereolegical office is 7 - 18 mph. "Average annual wind speeds range from 7 m.p.h. in parts of south Leinster to over 18 m.p.h. in the extreme north."
This converts to 3.12 - 8.04 m/s, I have seen claims by a wind turbine provider that the average wind speed in Ireland is 9.3 m/s - 14.16 m/s. This does not correlate with the met office and should be ignored.
Two other things to remember when looking at wind turbines:
1) Wind Turbines are rated at 12m/s. If they are running at 6m/s the drop in power is roughly 87.5%, i.e. a turbine rated at 1 kW @ 12m/s will produce 125 Watts at 6m/s.
2) Met Eireann carry out wind speed analysis at 10m above ground level. If a turbine is placed at 6m above ground level there will be a reduction of wind speed by about 7%, resulting in a performance drop of another 2.8%, or a total drop to 101 Wattsfrom the original 1kWs offered. This does not include electrical losses in the overall system, which could be as high as 11.5%. This leaves a 1kW Turbine producing about 89 Watts of power at a height of 6m.
Sorry for the bad news. These figures are theoretical only and field tests may prove me wrong, but I can reference them all.
Hi Michael,
Thank you for the great explanation. Always nice to see facts and figures that relate to real scenarios. It helps to explain them.
Liam
Hi
I have been looking into these turbines. I found they are rated at 33 mph, being the obtimum wind speed, but they can be produced to give their best obtimum pitput at any wind speed. However if you make them to give their best output at say 10 MPH, you then have to switch them off at say 16 mph to aviod damage. If you make them to give out their best output at say 40 mph, then they will not begin to give an output below say 20 mph
Do you know if the grid charges wind companies for grid power consummed by the turbines to energise the alternator rotor and defrost the blades and keep the gear oil heated.
Val
Hi Val,
Thanks for the comment.
Wind turbines can be rated a low wind speed but still operate at higher speeds. There are several wind turbines that are rated at 10 m/s but can generate wind speeds at 15 m/s. The statistical occurrence of high wind speeds is low so the wind turbine does not suffer.
The reason why manufacturers may choose to rate their turbine at 20 m/s is that it makes it look very good. e.g. if they rate a turbine at 2kw at 20 m/s it may only generate 600 Watts at 10 m/s.
The average wind speed in the UK is 5 m/s, the average wind speeds in ireland are between 4 -6 m/s except in extreme locations (these are very few)
One should be more concerned about a turbine operates at low speeds rather than high speeds.
If a turbine draws power to perform a mechanical/maintenance operation then the power has to come from somewhere, if it does not come from the turbine is must come from the main supply. If it comes from the main supply then you will be charged.
Liam