Exhibit 23.1
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the incorporation by reference in Registration Statement No. 333-132933 on Form S-8 of Duke Energy Corporation, of our report dated June 23, 2009, appearing in this Annual Report on Form 11-K of the Duke Energy Retirement Savings Plan for Legacy Cinergy Union Employees (Midwest) (the “Plan”) for the year ended December 31, 2008.
| /S/ MCCONNELL & JONESLLP |
| Houston, Texas |
| June 26, 2009 |
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