AES Reaches Agreement to Sell CILCORP to Ameren Corporation for $1.4 Billion.

Business Editors

ARLINGTON, Va.--(BUSINESS WIRE)--April 29, 2002

The AES Corporation (NYSE: AES) today announced an agreement with the Ameren Corporation (NYSE: AEE) to sell 100 percent of its ownership interest in CILCORP, a utility holding company whose largest subsidiary is Central Illinois Light Company (CILCO), in a transaction valued at $1.4 billion including the assumption of $860 million of debt and preferred stock.

The transaction also includes an agreement to sell AES Medina Valley Cogen, a 40 MW gas-fired cogeneration facility located in CILCO's service territory.

The transaction value equates to an equity purchase price in excess of $500 million (subject to certain closing adjustments) which approximates the book value of AES' investment in CILCORP and Medina Valley. AES acquired CILCORP in October 1999 in a transaction valued at $1.3 billion including the assumption of $412 million of debt and preferred stock and the payment of $885 million in cash to CILCORP public shareholders. AES financed its acquisition of CILCORP with $469 million of equity and the balance with acquisition debt.

The agreement includes all of CILCO's electric and gas utility assets and the cogeneration assets of Medina Valley. The sale of CILCORP by AES was required under the Public Utility Holding Company Act (PUHCA) when AES purchased IPALCO, a regulated electric utility based in Indianapolis, Indiana, in March 2001.

The transaction is subject to regulatory approvals by the Illinois Commerce Commission (ICC), the Federal Energy Regulatory Commission (FERC), the Securities and Exchange Commission (SEC) and expiration of the waiting period under the Hart-Scott-Rodino Anti-trust Improvement Act. AES expects the sale of CILCORP to close in the first quarter of 2003 and to receive cash proceeds in excess of $500 million.

CILCO, an integrated electric and gas utility based in Peoria, Illinois, serves more than 200,000 electric and gas customers in central Illinois. Ameren, an integrated electric and gas utility with more than $10 billion in assets, provides electric and gas service in Illinois and Missouri. With the acquisition of CILCORP, Ameren will rank as Illinois' second largest electric utility.

Dennis W. Bakke, AES President and Chief Executive Officer, commented, "AES conducted a comprehensive and deliberate sale process, dealing with multiple interested parties. The outcome is a sale agreement that we believe meets the needs of both AES shareholders and the CILCO community."

"This sale will significantly contribute to the long-term strength of AES' balance sheet in keeping with our commitment to improve liquidity. The sale price is in line with our expectations. Ameren's strong financial position and high ranking for quality service give us confidence that the proposed transaction will obtain all required regulatory approvals."

"We listened closely to the concerns of local stakeholders during the sales process. In Ameren, we have selected a company with the resources and demonstrated commitment to continue CILCO's tradition of high quality service and community support."

Lehman Brothers acted as financial advisor to AES in the transaction.

"Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: Statements in this press release regarding AES Corporation's business, which are not historical facts are "forward-looking statements" that involve risks and uncertainties. For a discussion of such risks and uncertainties, which could cause actual results to differ from those contained in the forward-looking statements, see "Risk Factors" in the Company's Annual Report or Form 10-K for the most recently ended fiscal year.

About Ameren Corporation

Ameren, a $10-billion-asset company based in St. Louis, Mo., provides energy services to 1.5 million electric and 300,000 natural gas customers over 44,500 square miles in Illinois and Missouri.

AES is a leading global power company comprised of competitive generation, distribution and retail supply businesses in Argentina, Australia, Bangladesh, Brazil, Cameroon, Canada, Chile, China, Colombia, Czech. Republic, Dominican Republic, El Salvador, Georgia, Germany, Hungary, India, Italy, Kazakhstan, the Netherlands, Nigeria, Mexico, Oman, Pakistan, Panama, Qatar, Sri Lanka, Tanzania, Uganda, Ukraine, the United Kingdom, the United States and Venezuela.

The company's generating assets include interests in 177 facilities totaling over 59 gigawatts of capacity. AES's electricity distribution network has over 727,000 km of conductor and associated rights of way and sells over 108,000 gigawatt hours per year to over 16 million end-use customers.

AES is dedicated to providing electricity worldwide in a socially responsible way.

For more general information visit our web site at www.aes.com or contact investor relations at [e-mail].