The first thing you notice is the silence.

Even when the air conditioning is on, this is a quiet bus. Call it bookmobile quiet. And when the A/C is off, it’s almost library silent.

This is not a bus where passengers have to be loud talkers in order to carry on a conversation. I almost expected to get shushed while riding on the state’s first electric bus.

In the race to be the greenest, the Port Authority of New York and New Jersey has put the first electric buses on the road in New Jersey. It purchased 18 Proterra electric buses to use in shuttle service at its three major airports. The first buses went in service at Newark Liberty International Airport on Thursday, running on the airport’s 24/7 shuttle.

I’m a regular bus rider and grew up in Queens, New York, where diesel smoke bleaching buses were part of the streetscape. Over the years, diesel bus technology has gotten better and cleaner, but I still roll up the windows and hold my breath when I’m driving behind one or standing in the street when a diesel goes by.

There is no stench around the electric bus. The only thing you notice is that “new bus” smell and the odor of whatever else is around you. Note to self: don’t ride an electric bus after eating garlic bread.

Besides smell, the biggest difference between this bus and a diesel is in your ears. There is no growling, rumbling engine, loudly laboring to move it. Except for an occasional hiss from the air brakes, the electric bus is silent when sitting at curb side.

Under acceleration, the loudest sound in the cabin is the faint whine of electric motors, it’s sort of a quieter version of the sound subway and PATH trains make when accelerating. Even that gets drowned out to a degree, when the air conditioners or heat is turned on.

There are the typical bus door and seat rattles when it goes over bumps, this isn’t a Lexis.

Just like the icon on your iPhone, this indicator on the states first electric bus shows how much power is left. The bus can be charged in three hours.

But, an idling diesel bus, parked next to an electric, is louder when it’s sitting still than its cleaner cousin is under acceleration.

The price tag is roughly $750,000 per bus, about $100,000 more than a conventional diesel bus, said Rick Cotton, Port Authority executive director. Fuel and maintenance cost savings compared to diesel buses will offset that price tag, he said. The buses travel 250 miles before requiring a charge and can recharge in 3 hours, which is done in off-peak hours.

“This is my second ride," he said. “It’s much quieter than the average bus.”

But clean air is the biggest reason for the switch.

“We get the satisfaction of knowing we’re helping the environment…we’re trying to put our money where our mouth is when it comes to environmental sustainability,” Cotton said in an interview on and outside the bus.

Last year, the authority made news after officials pledged to follow the Paris Climate Agreement and reduce emissions by 35% by 2025 and by 80% by 2050. While the electric buses are part of the plan, using solar power at airports and other facilities and fuel cell generated electricity at 1 World Trade Center are part of the authority’s effort to reduce emissions.

The first electric bus in the state waits for passengers at Newark Liberty airport on Thursday and will run on the airport shuttle.

The Port Authority plans to replace all 36 buses in the airport fleet with electrics, which is in line with a larger plan to have electric vehicles comprise 50% of the authority’s light duty fleet, which is underway, he said.

Adding to the fleet of electric vehicles “goes a long way” to reducing pollution and respiratory diseases, such as asthma caused by emissions and particulate, said Jeff Tittel, NJ Sierra Club director.

“We need to do a lot more,” he said. “The biggest pollution comes from cars, trucks, buses and (diesel) trains.”

The authority doesn’t plan on experimenting with the other types of clean buses, such as vehicles powered by hydrogen that leave water vapor behind.

“We’re committed to electric buses,” Cotton said.

In January, NJ Transit announced it would will try out eight electric-powered buses expected to hit the streets as part of a road test in Camden.

The authority is “learning as it goes along with the electric bus program, Cotton said.

“Airport geography is perfect, it’s flat and a compact route,” Cotton said. “Public transit has different challenges."

Environmentalists lobbied NJ Transit last August to start using electric buses in cities such as Newark, Camden and Jersey City, which they said have high rates of respiratory diseases caused by exhaust and particulate from diesel vehicles.

“It should put more pressure on NJ Transit to end the current practices,” Tittel said. “The should cancel (the remaining) diesel order and buy electric buses and hybrids.”

Larry Higgs may be reached at lhiggs@njadvancemedia.com. Follow him on Twitter @commutinglarry. Find NJ.com on Facebook. Have a tip? Tell us. nj.com/tips.

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