A unit of Texas power company Energy Future Holdings, Texas Competitive Electric Holdings Co LLC, filed for bankruptcy on Tuesday, seven years after Energy Future's record leveraged buyout stacked it with debt just as electricity prices plunged.

The unit listed assets and liabilities in excess of $1 billion in court documents filed in the U.S. Bankruptcy Court in Wilmington, Delaware.

Energy Future was created in 2007 by the $45 billion leveraged buyout of TXU Corp, a deal led by KKR & Co, Goldman Sachs Group Inc's private equity arm and TPG Capital Management.