The next step the nation’s move toward energy independence is still likely to come from corn and soybeans, a panel of industry experts told the Iowa Renewable Fuels Association in Des Moines, Iowa, Tuesday.

Under the federal mandate for fuel companies to use renewable sources, the Renewable Fuel Standard, the amount of corn and grain-based ethanol tops out at 15 billion gallons in 2015. By 2022, the nation will be using 36 billion gallons total of fuels from renewable sources. The public may think of switchgrass and other new crops as the next source of that clean energy but in the short run, at least, it’s still going to be from corn and soybeans.

“The biodiesel industry is ready to move forward as America’s first commercially available advanced biofuel,” said National Biodiesel Board Chairman Gary Haer of the Renewable Energy Group.

The EPA defines an advanced biofuel as one that cuts greenhouse gas emissions by at least 50% and doesn’t compete with the food supply. Biodiesel cuts emissions by up to 86% and qualifies, he said. By 2022, the federal mandate will require the use of 4 billion gallons of advanced biofuels, which can include just about any renewable fuel except corn-based ethanol.

This year the mandate for biomass-based diesel fuel is 800 million gallons, but out of nearly 14 billion gallons of all renewable fuels to be used this year, 1.35 billion will be advance biofuels. Since advanced biofuels can include biodiesel, it raises the amount that can be blended into diesel fuel above the 800 million gallon mandate.

Haer said the industry already has 2.2 billion gallons of biodiesel capacity registered with the EPA. The industry is operating well below that after going through 2010 without the $1-a-gallon tax credit for biodiesel (which ended in 2009 and wasn’t renewed by Congress until late December). Haer said the U.S. has about 3 billion gallons of total biodiesel capacity that could be used to meet the demand for advanced biofuels.

Early stages of cellulosic ethanol will be associated with corn for DuPont Danisco Cellulosic Ethanol LLC, said Kyle Althoff,  director of feed development for the joint venture.

“We look at closely working with some of the existing corn ethanol plants that are out there today,” said Althoff.

In the past year DuPont Danisco has contracted with farmers in Iowa, Nebraska and Indiana to be able to bale corn stover that it plans to test at its 250,000 gallon capacity demonstration plant in Vonore, Tennessee, Althoff told Agriculure.com later. His company is also working with DuPont’s Pioneer Hi-Bred International and Iowa State University to evaluate the effects of different tillage and planting methods as well as methods of harvesting the stover. DuPont Danisco has hired custom crews to put up large square bales.