1. Erik Duncan, Invenergy LLC October 20, 2009 The Cost of Developing and Constructing Wind Farms

2. Invenergy 2 Overview Invenergy Background Development Costs Construction Costs Key Cost Drivers Other Costs Questions

3. Invenergy 3 Invenergy - Overview U.S. company, based in Chicago, IL Over 300 employees worldwide Business model includes : Development Construction management Financing Operation and maintenance Long-term ownership Recognized by utilities, construction companies, and turbine manufacturers as a proven and reliable business partner 2 nd Largest U.S. Purchaser of General Electric Wind Turbines (over 3,000 MW of orders between 2005 & 2010) Largest privately-owned wind energy developer in the U.S. Six U.S. natural gas generation projects in operation or construction (2,100 MW)

4. Invenergy Invenergy Project Locations

5. Invenergy Invenergy Projects Buffalo Mountain Oliver Springs, TN Judith Gap Wheatland Co., Montana

6. Invenergy Invenergy Projects Forward Energy Center Fon-du-Lac Co., Wisconsin Spring Creek Wind Farm Logan Co., Colorado

7. Invenergy 7 Typical Development Process Assumptions: No lengthy appeals Single year of wildlife studies Year1234 Site Selection / Feasibility Permitting Studies /Applications Permitting Process Power Marketing Interconnection Studies Interconnection Construction Construction

8. Invenergy 8 Development Costs (100 MW Project) ItemLowMidHigh Site Control100,000300,000500,000 Wind Analysis170,000310,000450,000 Interconnection200,000300,000400,000 Envir. Studies100,000500,0001,000,000 Permitting0500,0001,000,000 Litigation/Appeal0200,0002,000,000 Miscellaneous450,000800,0001,100,000 TOTAL1,020,0002,910,0006,450,000

9. Invenergy 9 Development Cost Drivers Competition Site Complexity Regulatory Environment Site-specific Permitting Issues Local Support / Opposition Appeals/Litigation

10. Invenergy 10 Construction Costs (100 MW Project) ItemLowMidHigh Wind Turbines100,000,000137,500,000175,000,000 Engineering & QC3,000,0004,000,0005,000,000 Erection3,000,0005,000,0008,500,000 Civil14,300,00017,000,00021,500,000 Electrical15,900,00020,000,00023,800,000 Transmission06,000,00012,000,000 Miscellaneous1,150,0003,500,0005,500,000 TOTAL134,350,000193,000,000251,300,000

11. Invenergy 11 Construction Cost Drivers Turbine Costs (Demand) Site Complexity Regulatory Environment Interconnection Costs Commodity Costs

12. Invenergy 12 Additional Costs (Not Included) Multi-year preconstruction studies Construction contingencies Delay costs Transaction costs Financing costs

13. Invenergy Questions?