Metro General Manager Richard Sarles and Robert Golden Jr., assistant chief engineer of vehicles, examine the engine compartment of a new hybrid bus in May 2011. (James A. Parcell/For The Washington Post)

The hybrid buses made by New Flyer have a “potential for an electrical short within the energy storage system,” according to Metro chief spokesman Dan Stessel.

He said Metro was notified last week by New Flyer of the defect in the buses and he said New Flyer submitted Friday its notice of recall to the National Highway Traffic Safety Administration (NHTSA).

Stessel said Metro has received a “certification” from BAE Systems, which makes the energy storage system in the bus, and New Flyer that the buses are safe to use, and they will continue in operation. Metro is expected to receive five additional buses from New Flyer of America, based in Winnipeg, Canada, later this year, as part of a $89.3 million contract for 152 buses.

The buses Metro has now are being used in Montgomery County and the District on various routes.

Stessel said New Flyer and BAE Systems are working to retrofit the buses to fix the problem. They are paying for the cost to do the work. He did not know immediately how much it will cost.

So far, Metro has received 147 of the New Flyer buses. Only 47 of those buses have energy storage systems made by BAE Systems; the rest are made by another manufacturer, Stessel said.

Metro is expected by the end of the year to get five more of the New Flyer buses that have BAE Systems work in them. Those five, Stessel said, will be rid of the electrical problem before they are delivered to Metro.

There have been 10 incidents involving electrical shorts in the battery system in the past three years among 2,200 New Flyer buses in North America, according to Stessel. He said those incidents involved no smoke in the passenger compartment area and no one was injured, according to information provided by BAE Systems.

Last May, when Metro rolled out the new buses, 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.

On a tour of the new buses, Jack Requa, assistant general manager of Metro’s bus service department, called the New Flyer Xcelsior XDE40 the “Prius of buses.”

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. They also feature an improved ramp for wheelchairs that can work manually if the electronics break.

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.