LAFAYETTE — Two natural gas-powered city buses are scheduled to be rolling by the end of the month in the ongoing initiative to wean the municipal transit service off diesel fuel.

City-parish officials on Thursday unveiled one of the buses, which featured a University of Louisiana at Lafayette-inspired design and the “Fueled by Nature” logo that’s on the five natural gas buses the city bought in 2011.

Lafayette plans to gradually phase out all diesel buses and transition to natural gas — touted as a cheaper and cleaner-burning alternative.

The switch dovetails with efforts by the natural gas industry to find new markets for gas supplies that have grown dramatically in recent years with new “shale” finds in Louisiana and elsewhere.

“It supports an industry that we know is critical to our economy,” City-Parish President Joey Durel said.

Louisiana Oil and Gas Association Vice-President Gifford Briggs said Lafayette is the only city he is aware of in the state besides Shreveport that is moving to a natural gas bus fleet.

Besides the two new buses announced Thursday, three more new natural gas buses are scheduled to arrive later this year, and the city is refurbishing 12 used natural gas buses that were given to Lafayette by a transit system in Georgia that no longer needed the vehicles.

All of those buses should be on the road before the end of the year, City-Parish Transit and Parking Manager Mike Mitchell said.

That would bring Lafayette’s natural gas bus fleet up to 22 buses.

“The majority of the in-service vehicles will be natural gas,” Mitchell said.

He said the remaining 16 diesel buses are expected to be phased out by 2020 or 2021.

City-parish government is also converting normal fleet vehicles to natural gas, and last year built a new, specialized natural gas fueling station at the public work’s facility on East University Avenue.

The unveiling of the bus on Thursday was on the campus of ULL, and the city is in talks with the university to begin offering a shuttle service there.

“We are still in negotiations with them,” Mitchell said.

The two new natural gas buses cost $465,000 each, but the expense was covered with federal funds through the American Recovery and Reinvestment Act of 2009, according to information from city-parish government.

Lafayette has also received more than $2 million in state and federal grants to help fund costs related to the new natural gas fueling station, natural gas vehicle conversions and upgrades needed to work on natural gas vehicles at the city maintenance facility.

The savings with the new buses so far have been significant — an average of about $4,300 a month in fuel costs per diesel bus compared with $1,400 to $1,700 per natural gas bus, according to figures from the City-Parish Traffic and Transportation Department.