Peoria, Ill., February 2, 2011 — Ameren Illinois is working to restore service to customers without electricity due to a massive winter storm that stretches across 20 states.

Outages are expected to continue on the subtransmission, transmission and distribution systems. The service recovery effort will continue to be hampered by high winds, ice, heavy snow, subzero wind chills and extremely hazardous road conditions.

About 1,600 skilled field and support personnel from Ameren Illinois and electrical contracting allies are being directed in the service restoration effort by the Ameren Illinois Emergency Operations Center. About 35,800 Ameren Illinois customers are without power.

The leading cause of outages is galloping conductors. This phenomenon occurs when strong winds blow across ice-covered power lines. This can cause power lines to bounce violently. This causes lines to strike each other, resulting in outages. The galloping lines also can break crossarms and poles, sending wires to the ground, causing outages.

Galloping conductors can be expected to continue to cause outages as long as strong winds persist. The high winds also have caused damage to various components of the distribution system at some locations.

Ameren Illinois has deployed four Storm Trailers to aid in the restoration effort. Storm Trailers are mobile warehouses with the supplies field crews need to restore service. These trailers are placed in strategic locations and are moved as restoration requirements dictate.

Ameren Illinois delivers energy to 1.2 million electric and 813,000 natural gas customers in downstate Illinois, and our mission is to meet their energy needs in a safe, reliable, efficient and environmentally responsible manner. Our service area covers more than 1,200 communities and 43,700 square miles.