The long awaited wind integration study from EnerNex, commisioned by the MN dept. of Commerce, has been released and is available for download from the Department of Commerce's website:
http://www.state.mn.us
click on Energy Info, then click on the wind tab, at the bottom of the wind page is a link to the study.
Results show that the Xcel system can accomodate 1500MW of wind with a 0.47 cent per kwhr cost addition- which includes an additional regulation requirement of 8 MW, plus modifications to ramp rate of current regulation (generators that ramp up and down to more closely match load). At times this 1500 MW of wind would represent 20-30% of the load on Xcel North's system, clearly this is a significant amount of wind on the system and its additional cost burden is low enough to allow wind to compete with or beat the prices of all other forms of new generation being bid in the state. This study has alot of information of interest to all interested in large scale wind integration for a Midwest utility, and the MN wind resource- nicely modeled by the new MN wind modeling company, Windlogics.

For anybody keeping track, the MN legislature passed a directive to do a statewide wind integration study in May. Here's a short summary:

Wind Integration Study
The legislation requires all electric utilities to finance and participate in a statewide study of the impacts on reliability and cost of increasing wind capacity to 20 percent of Minnesota retail electric sales by 2020. The Reliability Administrator shall manage the study and appoint a stakeholders group with experience in engineering and expertise in power systems or wind energy to review the study's proposed methods and assumptions. The study must be completed by November 30, 2006.