PLAINFIELD, Ind., July 5, 2002 -- The Indiana Utility Regulatory Commission Wednesday allowed PSI Energy to begin recovering a portion of the costs it is incurring to comply with federal and state environmental mandates.

Initially this rate adjustment will result in an approximate 1 percent increase for PSI Energy customers overall.

In total PSI plans to invest more than $500 million in nitrogen oxide emission reduction equipment due to more stringent federal and state environmental laws. Some of the environmental projects at PSI's power plants include selective catalytic reduction equipment and low-nitrogen oxide burners, which reduce nitrogen oxide emissions and burn coal more cleanly.

In the IURC order PSI received approval to recover the financing charges on these environmental investments made through December 31, 2001, which total nearly $180 million.

The increase amounts to an average impact of 81 cents per month for a residential customer using 1,000 kilowatt-hours of electricity. Under Indiana law, PSI can file semi-annually to recover financing costs relating to additional environmental expenditures.

A subsidiary of Cinergy Corp., PSI Energy is Indiana's largest electric supplier, serving more than 700,000 customers in 69 of the state's 92 counties.