* NRG Q2 EPS $2.53 vs last yr $0.81
* NRG Q2 rev up 7 pct $2.27 bln
* Alliant Q2 EPS $0.44 vs est $0.47
* Alliant Q2 rev $819.5 mln vs est $768.1 mln (Follows alerts)
Aug 4 NRG Energy posted a three-fold increase in second-quarter profit helped by higher retail sales and an increase in customer count, and the power company said its Chief Financial Christian Schade will resign in early September.
The company said it expects to name a new CFO in the near future.
For the full year, NRG expects earnings before interest, taxes, depreciation, and amortization (EBITDA) of $1.9-$2 billion, up from its prior outlook of $1.75-$1.95 billion.
The Princeton, New Jersey-based Company said it also expects $300 million of share repurchases by year end.
For April-June, the company posted a net profit of $618 million, or $2.53 a share, up from $208 million, or 81 cents a share, last year.
Revenue rose 7 percent to $2.27 billion.
Separately, smaller peer Alliant Energy posted second-quarter adjusted profit of 44 cents a share, compared with analysts' estimates of 47 cents a share.
The Madison, Wisconsin-based company's revenue rose 10 percent to $819.5, compared with analysts' estimates of $768.1 million.
NRG shares closed at $23.66 on Wednesday on the New York Stock Exchange, while Alliant shares closed at $39.23. (Reporting by Vaishnavi Bala in Bangalore; Editing by Gopakumar Warrier)