Iowa’s biodiesel industry set a production record in 2011 even though three plants were closed, according to the Iowa Renewable Fuels Association.

The ten plants remaining in operation had a combined output of 169 million gallons. By the end of the year, they were producing at an annualized rate of over 250 million gallons, the association said Thursday.

“The reinstatement of the biodiesel tax credit combined with the renewable fuels standard jump-started demand and Iowa was quick to respond,” Iowa Renewable Fuels Association Executive Director Monte Shaw said in a statement issued by the group.

The state’s previous record for biodiesel production was 85 million gallons in 2009. In 2010, after the last time the biodiesel tax credit lapsed, Iowa produced 48 million gallons of biodiesel.

The biodiesel tax credit will expire again at the end of the year because Congress has not renewed it. Shaw said the industry will not completely shut down as it did in much of 2010 because the Renewable Fuels Standard is in place.

“But the uncertainty of reinstatement will undoubtedly depress demand,” Shaw said. “Congress must act quickly in 2012 to extend the tax credit.”