While filling up, the driver of a diesel tractor-trailer looks over a CNG counterpart during a demonstration of Compressed Natural Gas infrastructure installed in Sheboygan.
They may not be quite as ubiquitous as petroleum stations, but the number of public and private refueling sites for alternative fuels is on the rise in Wisconsin.
Lorrie Lisek, executive director of Wisconsin Clean Cities, said the development of infrastructure to support compressed natural gas is on the fast track in the state and there are steady increases across the board for other alternative fuels.
"Compressed natural gas is really on the cutting edge and what everyone is interested in," she said. "It has to do with cost and being produced domestically ... The infrastructure is coming ...