The Deal That Even Awed Them in Houston
Texas Pacific Group, Blackstone Group, Kohlberg Kravis Roberts and Hellman & Friedman, which purchased Houston's electric utility Texas Genco for $900 million in 2004, are selling company to NRG Energy for gain of $5 billion; deal causes jaws to drop in Houston's energy circles and angers and perplexes people who are feeling sting of surging electricity prices (Market Place column) (M)