"In the course of its design life a single 3MW wind turbine will supply clean energy to the equivalent of some 6,000 to 7,000 tons of carbon emissions.

The carbon emission cost of installing that turbine and putting it into service amounts to somewhere between 26,000 and 41,000 tons of carbon emissions" (Teribus, 14 Aug14 - 04:34 AM)

You don't cite a source for your figures, Teribus, so I don't know where you got them from, but they didn't sound correct to me, so I performed my own calculation (an energy balance rather than a CO2 balance):

This site indicates that the energy "used" in setting up a 3MW turbine is 4.3GWh including "the energy used during the manufacturing, operation, transport, dismantling/disposal and transmission," so it sounds comparable to your baseline. Assuming it has a 20% power-factor (effectively producing 0.6MW = 3MW x 20% continuously) then it has produced its own "cost" in energy in 4.3GW / 0.6MW hours, or approximately 10 months.

After 10 months, it's all payback!

My figures do not include any energy consumed by the backup generators which, I admit, must be kept continually spinning.