The rumble of diesel school bus engines has been replaced by the soft chimes of trolley bells on some routes in the Hughson Unified School District.

On Wednesday, four new electric buses began ferrying students to and from school, making Hughson the largest district in Stanislaus County to use the pollution-free vehicles. The move was made possible thanks to a $1.6 million grant Hughson received from the state of California, which covered most of the cost of the 84-passenger buses that are priced at $420,000 each.

The new buses replace four diesel-powered vehicles that all are about 30 years old, according to Lara Haverly, the district’s transportation supervisor. It was Haverly who heard about the grant while at a conference in November 2019. She quickly applied and the district learned in August 2020 it had been awarded the money.

The buses were built in Porterville, near Fresno. It was hoped they would be ready in time for the start of school last August, but parts and supply chain issues delayed their delivery.

“We’re so excited,” Haverly said. “We’ve been waiting for them for so long.”

The new buses will be used on the four routes that service the district’s 2,100 students. Haverly said about 400 students are eligible for bus transportation, but daily ridership averages about 280.

The sleek new buses have a range of about 150 miles. Hughson’s longest round trip is about 40 miles to La Grange and back, made in the morning and again in the afternoon.

One of the most noticeable differences in the new buses compared to the ones they replaced is the noise – or lack of it. While the diesel engines have a familiar roar – especially as the buses begin to move – the electric buses are quiet. For safety reasons, that’s why the trolley chimes kick in at speeds of less than 20 mph. The sound alerts pedestrians and others near the bus that it’s moving.

“They accelerate really fast,” Haverly said during a test drive in March. “They’re really nicely put together. And they’re lighter than the old buses.”

In addition to its share of the buses’ cost, the district will invest about $140,000 to expand its maintenance and bus parking area behind Hughson Elementary School, where the buses will be housed and the required charging stations located.

When the district received the grant 18 months ago, it initially projected it would save about $38,000 annually on fuel and maintenance during the 25-year expected lifespan of the electric buses compared to diesel alternatives – a total of about $1,152,200. But given the increased price of diesel fuel these days, that number has only gotten higher.

Some of the yearly savings will be set aside to replace the four large batteries every eight to 10 years that power the new buses, said Andy Fontana, the district’s maintenance and operations director. The district also will apply for energy-related rebates of up to $8,000 per bus from the Turlock Irrigation District, he said. In addition, Fontana is exploring the idea of selling carbon credits related to the new buses, which could net the district another $15,000 to $20,000 per year.

One of the requirements of the state grant was that the old buses be taken out of service and crushed. That will happen soon, Haverly said. The district still has eight diesel buses, which will continue to be used for longer trips by students and sports teams.

Reducing energy use and pollution by investing in electric buses fits with the district’s long-term strategy of being a responsible member of the larger community, Hughson Superintendent Brenda Smith said.

“I want people to understand we’re doing this to get those old buses out of the field,” she said. “It’s the right thing to do … and we got a sweet deal to do it.”

The grant money from California comes from a $423 million settlement the state reached in 2018 with Volkswagon after the German automaker admitted cheating on nitrogen oxide emissions testing for its vehicles.