US ethanol production for September dropped to its lowest level in at least 27 months, in large part because of plant shutdowns. Ethanol plants produced 983.9 million gallons in September, down 9.4 percent from August. The previous low since the EPA started keeping such records in July 2010 was the 1.051 billion gallons produced in February 2011. The numbers come from the US Environmental Protection Agency's (EPA) Moderated Tracking System website and were reported in the energy-pricing publication Platts.

Among recent ethanol-factory shutdowns was Abengoa in Madison, WI, which was closed for maintenance. Usually, it makes 88 million gallons of ethanol per year. The issue of ethanol production has grown in importance as President Barack Obama and Republican candidate Mitt Romney debate over the concept of alternative fuels and US energy independence. Biodiesel production in September was also down for the fourth straight month.

Meanwhile, the EPA's 2010 decision to raise the nationally available ethanol blend to 15 percent from 10 percent withstood its most recent challenge from various trade groups when a lawsuit against the regulator was thrown out in August.