SIOUX FALLS, S.D. — A South Dakota corn ethanol plant will soon be making the transition to producing a fuel additive with a wider variety of uses.

Redfield Energy CEO Tom Hitchcock says the 50 million-gallon-per-year plant is teaming with Colorado-based Gevo to convert the facility in Redfield to a 40 million gallon per year butanol plant.

Gevo is also retrofitting a plant it owns in Luverne.

Butanol has traditionally been used as paint thinner, cleaner and adhesive, but as a fuel additive it contains more energy than ethanol and could be blended into existing cars at higher percentages.

The Redfield plant is a co-op owned by 650 members.

Hitchcock said Gevo is paying for the retrofit in exchange for an equity interest in the partnership.