PR-12-90 -- PSC Approves Ameren Missouri Request

Contact: Kevin Kelly (573) 751-9300

FOR IMMEDIATE RELEASE -- JANUARY 5, 2012

JEFFERSON CITY---The Missouri Public Service Commission has approved a request filed by Ameren Missouri which authorizes the electric company to exchange SO2 emissions allowances for NOx emissions allowances.

Ameren Missouri sought authority from the Commission for: 1) a one-time exchange of 1,050 surplus sulfur dioxide (SO2) emission allowances for 500 annual nitrogen oxide (NOx) emission allowances; an amount sufficient to comply with the requirements of the United States Environmental Protection Agency’s “Cross-State Air Pollution Rule,” which takes effect January 1, 2012; and 2) authorization to defer to Account 254, Other Regulatory Liabilities, the revenues associated with the SO2 portion of the proposed exchange of emissions allowances and to amortize the deferred amounts concurrently with the Company’s use of the acquired NOx allowances.

Based on the Commission’s independent and impartial review of the filings in this case, the Commission has approved the request determining Ameren Missouri’s proposed exchange of SO2  emissions allowances for annual NOx  emissions allowances is not detrimental to the public interest.

-30-

Case No. EO-2012-0158