SAN JOSE, Calif. (

TheStreet

) --

SunPower

( SPWRA) shares are tumbling Friday morning, a day after the company announced profit that topped Wall Street forecasts.

For the third quarter, the solar products manufacturer said revenue increased nearly 24% from the year-earlier period, coming to $466.3 million during the quarter. Analysts polled by Thomson Reuters expected sales at $420 million.

Net income fell to $12.8 million, or 13 cents a share, from the year-ago profit of $24.7 million, or 29 cents a share. Excluding items brought earnings per share to 42 cents, just beating the 40 cents a share forecast by analysts.

Still, shares were tumbling 12.6%, or $4.21, to $29.09 on Friday morning, with much blame placed on the company's outlook. SunPower trimmed the top end of its 2009 profit guidance, forecasting an adjusted earnings per share range of $1.15 to $1.25. Earlier, the solar concern had issued an estimate of $1.15 to $1.60. Full-year revenues are now expected to land between $1.43 billion to $1.5 billion, compared with the $1.35 billion to $1.7 billion forecast previously offered.

Elsewhere in the solar sector, shares of

First Solar

(FSLR) - Get Report

and

Ascent Solar Technologies

(ASTI)

were sliding by 2.2% and 4.1% each.

LDK Solar

(LDK)

was following suit like most solar shares on Friday, slipping 1.9% in the morning.

Yingli Green Energy

(YGE)

ADRs, too, were losing ground, down 3.6%, though

Canadian Solar

(CSIQ) - Get Report

shares were gaining 1.7%.

-- Written by Sung Moss in New York

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