Shares of

Calpine

(CPN)

, an electricity producer, climbed 10% after the company turned in better-than-expected first-quarter earnings, even as revenue declined.

Before the market opened Friday, Calpine said it made $32 million, or 7 cents a share, in the quarter, safely ahead of Wall Street estimates of an 11-cent loss, according to a Thomson Reuters survey of analysts.

A year ago, the company lost $214 million, or 44 cents a share, as it emerged from Chapter 11 protection.

Revenue, however, fell 14% to $1.68 billion from $2 billion in same period last year. Still, that's more than the $1.34 billion analysts were expecting for the just-ended quarter.

Calpine attributed its improved bottom line to successful hedging positions and some rigorous cost cutting. General and administrative expenses decreased by $7 million in the quarter compared with a year ago, the company said, and the hedges combined with higher heat rates in the quarter added at least $57 million to its commodity margins compared with the year-ago period.

Calpine reconfirmed its outlook for the rest of the year. It expects earnings before interest, taxes, depreciation and amortization to come in at $1.6 billion to $1.7 billion.

Calpine shares were trading midday Friday at $10.95, up more than 15%, on heavy volume.

Other big power companies also released their first-quarter financial statements this week. The results were mixed, with

Dynegy

(DYN)

,

Southern

(SO) - Get Report

and

Duke Energy

(DUK) - Get Report

posting year-over-year declines, and

FPL Group

(FPL) - Get Report

showing profit growth but missing expectations. Shares in all those companies were up modestly in Friday's session save Dynegy, up 20%, which posted a narrower-than-expected loss on Thursday.

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