Reuters: Norwegian solar industry group Renewable Energy Corp (REC) (REC.OL: Quote, Profile, Research, Stock Buzz) reported a 9.5 percent rise in core earnings for the second quarter, against expectations for a slight drop, and stuck to its 2008 revenue growth target. Shares in REC, one of the world’s biggest producers of solar-grade silicon and wafers for solar energy systems, initially rose more than 3 percent but lost the gains to trade down 0.33 percent at 150.50 crowns by 0805 GMT. The …