PR-11-90 -- PSC Sets Intervention Deadline In Ameren Missouri Electric Fuel And Purchased Power Adjustment Charge Case

Contact: Kevin Kelly (573) 751-9300

FOR IMMEDIATE RELEASE -- DECEMBER 8, 2010

JEFFERSON CITY—Union Electric Company d/b/a Ameren Missouri has filed a request with the Missouri Public Service Commission to adjust the fuel and purchased power adjustment charge (FAC) on the bills of its electric customers.

In its filing, Ameren Missouri states the proposed adjustment to customer rates reflects changes in its fuel and purchased power costs net of off-system sales revenues experienced during the four month period ending September 30, 2010. Ameren Missouri states the factors driving the increase were lower off-system sales revenue partially offset by lower fuel and purchased power
costs.

Base electric rates set in the last Ameren Missouri rate case reflect a certain level of fuel and purchased power costs less off-system sales revenue. The FAC reflects increases or decreases in those costs above or below those set in base rates. The FAC is designed to address fuel and purchase power costs and off-system sales revenue volatility.

The proposed adjustment, if approved, would raise the Rider FAC Adjustment for a residential customer using 1,100 kWh per month by approximately $1.24 per month effective in February 2011.

Applications to intervene and participate in this case must be filed no later than December 20, 2010, with the Secretary of the Missouri Public Service Commission, P.O. Box 360, Jefferson City, Missouri 65102.

Ameren Missouri serves approximately 1.2 million electric customers in Missouri.

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Case No. ER-2011-0153