Barry Brook with the assistance of Peter Lang has added a new post to his wind discussion, Wind and Carbon Emissions - Peter Lang Responds. The new post contains Lang's responses to the objections that were raised Barry's first post on Lang's assessment on wind. Lang sees the same things I do about wind:
The total electricity generation system must be able to provide peak power when there is no output from the wind turbines. When wind power is zero, or near zero, at the time of peak demand, we need total back up for all the wind generators. This is because electricity demand must be matched by supply at all times.
Lang counts the cost of a wind system
With wind power, we need the full capital cost of 1) the wind farms, PLUS 2) the conventional generators, PLUS 3) the transmission capacity for the full power output for each wind farm (despite the fact they produce, optimistically, just 30% of their rated power output on average), PLUS 4) the enhanced power and stability control systems. The cost of the wind generators does not offset virtually any capital cost for conventional generators in a system that has a substantial proportion of wind generation capacity.

The GHG emissions are the total of the full life cycle emissions from the wind farms, from the operation and maintenance of the wind farms and the enhanced grid, from the embedded emissions in the conventional generator systems, and from the emissions from the fuel combustion in the conventional generators operating in back up mode (which are higher per MWh than when operating at their optimum)
Clearly Barry Brook and Peter Lang has given us a major statement on the cost and effectiveness of wind generation systems.