​Mississippi Power says the Kemper Project clean coal power plant will be operational by April 30 and that the previously announced delay will cost an additional $70 million.

The company, a subsidiary of utility giant the Southern Company, revealed the information in a filing with the U.S. Securities and Exchange Commission Monday. The added expense brings the total cost to $7.237 billion.

The Kemper Project clean coal power plant has sometimes seemed to generate more lawsuits than megawatts from lignite coal for its owner, the Southern Company.

An investor, Alan Nussbaum, filed a lawsuit Monday in Delaware Chancery Court that seeks release of company books and records to ascertain if mismanagement was behind the multitude of delays plaguing Kemper.