Contracts signed today that will electrify #Caltrain. How that will boost rider capacity. At 6:07pm #abc7now pic.twitter.com/TxAljHeR6I — David Louie (@abc7david) August 16, 2016

BURLINGAME, Calif. (KGO) -- Monday marks a new era for Caltrain after a new contract was signed to convert the diesel-powered engines with an electric train system.Caltrain's lumbering diesel engines will be a thing of the past in about five years. The replacement is promising a long list of benefits, including compatibility with high-speed rail.The signing of the contract with two companies will usher in a new era for the Peninsula commuter rail service.Three-fourths of the workhorse diesel engines will be replaced with electric trains. The conversion will cost $1.9 billion and entail building power stations and an overhead electric cable from downtown San Francisco to Tamien Station, just south of downtown San Jose. The segment from that point to Gilroy will remain diesel. "We don't need to convert the entire fleet to electrify. The electrification system still can accommodate diesel service on the tracks, so that's the primary reason. Eventually we will be able to convert almost 100 percent of the fleet," Caltrain Executive Director Jim Hartnett said.Because electric trains accelerate and brake faster, Caltrain plans to operate six trains during rush hour in each direction, up from five, expanding ridership capacity.At least 60,000 people use Caltrain on an average weekday, and that number keeps growing yearly.Electrification will allow Caltrain and high-speed rail to be compatible in the future.Caltrain says key benefits will include reduced pollution and engine noise. However, loud train horns will stay in service at crossings for safety.Federal dollars are still coming in. The federal government favors projects that gets more people to use transit systems. "They could have gone under the full amount, but it really represents the $647 million will be forthcoming from the federal government," Palo Alto Rep. Anna Eshoo said.