A Sierra Club official says he hopes South Dakota will put a stronger focus on clear energy sources rather that fuels that leave a large carbon footprint.

Jim Margadant of Rapid City says South Dakota is clinging to an energy policy that tends to be "carbon-dependent."

South Dakota has 16 ethanol plants, but critics say the federally subsidized industry isn't all that environmentally friendly.

But Republican Senator John Thune disagrees. He says ethanol is better for the environment than traditional fuels. In his words: "You cannot tell me that something that comes from a product like corn isn't better than something that comes from petroleum for the environment."

Don Car, a spokesman for the Environmental Working Group, says he worries that more acres of fuel crops such as corn reduces the number of conservation acres, such as those in the Conservation Reserve Program.

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