Renewable Energy Group, the owner of a Geismar biodiesel refinery, reported its third-quarter profit dropped to $4.6 million, or 11 cents per share, down from $86.7 million, or $2.31 per share, a year ago.

Renewable said its results were affected by drops in average sales price for renewable fuels. The company’s 2013 results were boosted by tax benefits of $42.1 million, or $1.12 per share.

One of the company’s highlights included returning the Geismar facility to service after nearly two years of inactivity. The plant, which converts animal fat to diesel, can produce up to 75 million gallons of fuel per year.

The company said the Geismar plant began selling renewable fuel in October. Renewable completed its acquisition of the Geismar plant in June.