Ames-based Renewable Energy Group Inc., an advanced biofuels producer, on Monday reported a net income of $11 million, or 27 cents per share, for the second quarter. That's down from $23.1 million, or 63 cents per share, the same quarter a year ago. The company reported revenues of $332.9 million, down 13 percent from $384.7 million in the second quarter a year ago. "We believe the industry has worked through the excess inventory from year-end and we have seen demand increase since the first quarter," President and CEO Daniel Oh said in a press release.