The Indiana Department of Transportation (INDOT) will continue filling its bi-fuel propane autogas trucks with gasoline through March 1 to help residents coping with the propane shortage in the region.

Gov. Mike Pence directed INDOT to implement the practice on Jan. 23, as harsh winter weather and a propane infrastructure glitch dried up supplies in Indiana, Michigan, Wisconsin, and Nebraska. Nearly 10 percent of Indiana's residents use propane to heat their homes.

The state transportation agency stopped filling its 580 light duty bi-fuel trucks with propane autogas at that time, a spokesman for Gov. Pence told Government-Fleet.com. The fuel is dispensed in liquid form.

Gov. Pence declared an energy emergency in the state on Jan. 29. The U.S. Department of Transportation also issued a regional order for the Midwestern and Eastern regions that would allow transporters to move propane more freely.

Propane autogas is derived from propane, and tends to fluctuate in price during peak usage periods as more propane is used for residential heating. Vehicle fleets are considered "baseload" users because their fuel consumption is consistent and less tied to weather-related price spikes, said Tucker Perkins, chief business development officer with the Propane Education & Research Council.

"Our industry is counting on baseload like autogas to create the demand to drive the investment," Perkins said. "The problem is not a baseload customer. It's the heating-intensive peak users."

Cold weather in the Midwest and East led to record-high natural gas and propane storage withdrawals, challenges that stem from the October harvest of an unusually wet crop of grain and corn. As a result, a large amount of propane was needed to dry the crop before storage.

At the time, the Cochine pipeline, which provides 40 percent of the propane used by Minnesota suppliers, was shut down for repairs. Increasing global demand for propane — 20 percent of U.S. propane was exported in 2013 compared with 5 percent in 2008 — also caused the shortage, according to the Natural Propane Gas Association.