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Exhibit 23.4

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated February 28, 2008 relating to the consolidated financial statements and financial statement schedule, which appears in Union Electric Company's Annual Report on Form 10-K for the year ended December 31, 2007. We also consent to the reference to us under the heading "Experts" in such Registration Statement.

/s/ PricewaterhouseCoopers LLP
PricewaterhouseCoopers
St. Louis, Missouri
June 5, 2008

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Exhibit 23.4

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM