Correction: The original version of this article incorrectly stated that the new buses will save more than one gallon of gas per mile. The new buses will get more than 5 miles to the gallon versus 3.8 miles per gallon now. This version has been corrected.

Metro takes plenty of heat from bus riders, who complain that older buses break down too often and wheelchair lifts don’t work properly. But on Tuesday, transit officials showed off a new hybrid-electric bus that — in theory — is supposed to solve some of those problems.

The “New Flyer Xcelsior XDE40” is an updated version of Metro’s diesel buses, some of which are 15 years old. The new buses are supposed to break down less frequently and be more fuel efficient, getting more than 5 miles to the gallon versus 3.8 miles per gallon now. Some of Metro’s older buses break down every 3,000 to 4,000 miles, officials said. On average, a single Metrobus drives about 100 miles a day.

“This is the Prius of buses,” said Jack Requa, assistant general manager of Metro’s bus service department. “This is truly an efficient, intelligent bus.”

The transit system has an $89.3 million contract with New Flyer of America, based in Winnipeg, Canada, to buy 152 of the hybrid-electric buses for $571,737 each. The contract includes parts and training. Metro will begin to roll out the new buses this month and plans to have all of the new buses in service by the end of the year. The buses will be deployed in Montgomery County and the District on various routes.

Metro has replaced 401 of its older buses that ran on diesel with hybrids, and the new order will bring the hybrid fleet to 553. Metro has about 600 buses that run on diesel and a total bus fleet of 1,492.

Metro GM Richard Sarles checks out a new hybrid electric bus. (James A. Parcell/FOR THE WASHINGTON POST)

Metro officials said passengers should have a more comfortable ride in the new buses, which feature “better-cushioned, lumbar-supported” seats, handhold straps that hang down lower for those who stand, and an improved system to monitor heating and air conditioning.

The buses also have five security cameras; seats trimmed in Kevlar that are less susceptible to vandalism; a sensor- and voice-activated system to remind riders to not get too close to the doors while the bus is moving; and an onboard diagnostic test that allows drivers to monitor problems and download the data at the depot each day. It also features an improved ramp for wheelchairs that can work manually if the electronics break.

Keeping up the buses is no easy task, officials say. The system spends about $150 million a year to repair, replace and maintain the fleet. Each year, Metro takes about 100 of its buses that have been driven for about seven years out of service for an eight- to 10- week process that involves a “complete midlife overhaul,” bus officials say.

The buses and their parts go to two shops — one in Landover, the other in Bladensburg — where about 200 employees work with power tools buzzing to fix radiators, engines, transmissions and other parts. The rehabilitation of a bus costs about $122,000.

Post-rehab, Metro says, its buses can last another seven to seven and a half years.

“It’s not just about putting gas in them,” Requa said as he toured the rehab facility at Landover. “We’re working on taking out the older buses, making them more reliable and making them better.”

On a weekday, about 1,300 Metrobuses are in operation, driving a total of 148,000 miles and providing 443,000 passenger trips.

“They are constantly having the pedal to the metal with brakes, and there’s lots of idle time,” said Phil Wallace, managing director for Metro’s bus maintenance. “The only thing that’s rode harder is a garbage truck.”