Shares of global independent power producer AES Corp. on Wednesday shed almost half their value after the company warned it would fall well short of 2001 earnings estimates.

AES was down $11.40, or 47 percent, to $12.85 in early trade on the New York Stock Exchange. The start of trading in the shares was delayed by an order imbalance.

On Tuesday AES cut its earnings per share estimates for 2001 to a range of $1.25 to $1.45 from a previous range of $1.75 to $1.90, citing poor currency exchange rates between the Brazilian real and U.S. dollar, lower U.K. power prices, and its inability to replace earnings anticipated from the planned acquisition of the Mohave power plant.

The company also said the Sept. 11 attacks on the World Trade Center and the Pentagon had exacerbated many of its problems.

Early Wednesday, analysts began cutting their ratings and earnings estimates for AES. UBS Warburg analyst Ron Barone cut his 2001 earnings estimate to $1.35 a share from $1.75, while Morgan Stanley cut its rating on the shares to "neutral" from "strong buy".

Prior to the company's earnings warning, analysts' consensus earnings estimate for 2001 was $1.78 a share, in a range of $1.60 to $1.90, according to Thomson Financial/First Call.

But many analysts were not surprised by the AES warning.

"They grew so rapidly, and they prided themselves on going toward what others were running from," said Raymond Moore, an analyst with Weatherly Securities. "Their financial structure and deals are very complicated."