SANFORD — What is big and yellow and looks ”“ but doesn’t sound or smell ”“ like any other school bus?

The answer is a propane-fueled bus, and there are 30 new ones operating in Sanford, ferrying students to classes five days a week.

The propane buses were put into service Sept. 2 by Ledgemere Transportation, the local subsidiary of Students Transportation of America. They’re the first propane-fueled buses Ledgemere has brought to its Maine sites, although a couple of school districts already have a few.

So far, drivers say they like them.

School officials and Ledgemere Transportation like them, too; the fuel is significantly cheaper ”“ though they get fewer miles to the gallon than traditional diesel buses ”“ they’re said to be quiet and safe, and they require less frequent maintenance.

Sanford School Department inked a new, five-year transportation contract with Ledgemere earlier this year. The first year’s cost is about $1.6 million ”“ about the same amount the district paid their previous transportation vendor. Price increases of the contract over the next four years are pegged at an average of 3 percent, according to Assistant Superintendent of Schools Eric Knowlton.

Ledgemere hosted an open house at their new bus garage on Cyro Drive, in a south Sanford industrial park, Thursday. The new building was started June 26, and an occupancy permit was issued Aug. 29 ”“ just in time for the first day of school on Sept. 2.

Here, Ledgemere employs 30 bus drivers, 10 monitors and two mechanics, along with Sheila Beckwith-Hibbard, who is the manager of the Sanford operation. Beckwith-Hibbard has been with the company for 10 of her 24 years in the industry, working in a number of Connecticut locations before transferring to Sanford this year.

On Thursday, folks who are part of the school department, Ledgemere, propane supplier Down East Energy and others gathered to celebrate the new relationship and hear about the advantages of propane fuel.

“I love them, and they drive like a car,” said Ledgemere Transportation bus driver and safety trainer Nancy Stephan of the new buses. “And the biggest thing you hear from the kids is there are no fumes.”

Sue Daigneau, who has driven a school bus for a decade, said she really enjoys her job and interacts with the youngsters who ride her special education bus.

“I really enjoy what I do,” she said.

Daigneau said she’s noticed the heaters in the propane-fueled buses work more quickly than the ones in their diesel counterparts, warming up her passengers a lot quicker.

Patrick Vaughn, the chief operating officer for Student Transportation of America, said the company has about 150 propane-fueled buses in Texas, 250 in St. Paul, Minnesota and about 500 in Omaha, Nebraska.

“In Omaha, when it was 30 below last year, they were the only buses that would start,” he told the folks gathered at the open house.

Vaughn said propane-fueled buses are good for the environment and more cost effective to operate. He said 96 percent of carbons are removed from emissions with buses using propane fuel.

Knowlton said he’s pleased with Ledgemere and the propane buses, and that the district is looking for a long-term relationship with the vendor.

“Our expectations were high, and the results were even better,” he said.

The Blue Bird buses in use in Sanford are equipped with Ford 6.8 Liter V10 engines, with a direct-injection system for propane liquid installed by Detroit, Michigan-based Roush Cleantech. Derek Whaley, a representative for that company, said there are about 21 million vehicles worldwide that operate on propane, but only about 200,000 of them are in the United States.

In Maine, the U.S. Department of Energy’s website says two school districts, MSAD 6, known as Bonny Eagle, had 10 propane buses in use in 2012, and there are some propane-fueled school buses in use in Scarborough, as well.

According to Chris Kowalski of Downeast Energy, propane buses get 35 percent fewer miles per gallon than diesel-fueled buses, but the maintenance interval is doubled with propane-fueled engines. Right now, propane costs about $1.50 less per gallon than diesel fuel and is about $1 per gallon cheaper than gasoline.

As well as Sanford, Ledgemere Transportation provides school transportation services to Wells, York, Kittery, Parsonsfield and Lewiston. Nearby New Hampshire locations include Rochester and Portsmouth.

— Senior Staff Writer Tammy Wells can be contacted at 324-4444 (local call in Sanford) or 282-1535, ext. 327 or twells@journaltribune.com.