In its annual report last week, Airtricity stated that its wind farms have the capacity to produce 383 megawatts of electricity, enough to power 230,000 homes for a year.

These figures are impressive but quite meaningless.

The reality is that because output is so critically dependent on wind speed the overall output is only about 25pc of capacity and, on average, two thirds of this is wasted because it is generated when the power is not needed.

With the wind at their back Airtricity will be lucky to power 10pc of the number of homes stated.

This level of return simply does justify the environmental degradation caused by wind farms or the huge investment of resources involved.