Train Buffs: Do You Know What a ZEMU Is?

Electric multiple unit (EMU) and diesel multiple unit (DMU) trains, where electric traction motors or on-board diesel engines, respectively, are housed in one or more of the passenger cars, are not new. Denver's new A Line and Long Island Rail Road trains are EMUs, with the former receiving power by overhead catenary and the latter by third rail. See the last section of this post on a funding award for Caltrain EMUs.

In California, the SMART and Sprinter (light rail) trains are DMUs, and Tri-Rail in Florida operates Colorado Railcar diesel multiple units.

The Redlands Passenger Rail Project, one of the newest passenger rail projects in California being built by the San Bernardino County Transporation Authority (SBCTA), will operate diesel multiple unit trains. The nine-mile rail line between Redlands and San Bernardino is scheduled to begin service in 2021.

"The [$30 million] grant was awarded for a pilot program to deploy Zero Emission Multiple Unit [ZEMU] commuter rail vehicles on the Redlands Passenger Rail Corridor in San Bernardino," writes Assemblymember Eloise Gómez Reyes, who represents the district.

 With this funding SBCTA and the region will be national leaders in the deployment and testing of near zero and zero emission commuter rail trains... As this new technology grows in use we will see real benefits in reduced traffic congestion and reduced impacts on air quality while putting San Bernardino on the map as a testing hub for green technology.

According to CalSTA, the "conversion includes statewide testing that could impact future equipment acquisition for other rail services, like Metrolink, statewide."

The grant does not specify what type of technology, which presumably would be either battery-electric or fuel cell, also called hydrail, which would include near-zero emissions as the hydrogen could be burned rather than converted to electricity. A fuel cell train is already in operation in Germany, as a November 2016 post on the Coradia iLint, built by French rail technology provider Alstom, foreshadowed.

Another zero-emission trainset based on batteries is being developed by Swiss manufacturer Stadler Rail for Arriva Netherlands, reported Railway Pro last November. 

Diesel emissions

Even without conversion to zero-emissions technology, the DMUs on the Redlands line will be powered by the cleanest diesel engines available, known as Tier 4 compliant, meeting the highest standards set by the U.S. Environmental Protection Agency and the California Air Resources Board for off-road, diesel-powered engines.

Courtesy of Diesel Technology Forum

According to the projects August newsletter, the engines will be "[a]kin to a hybrid car in that the DMUs convert a cleaner diesel form of power to electricity to efficiently drive the vehicles to their destination.

Transit and Intercity Rail Capital Program award for Caltrain electrification

While electrification construction has begun, having received a $647 million Federal Transit Administration grant that the Trump administration initially delayed, the Peninsula Corridor Joint Powers Board, which owns and operates the Caltrain line operating from San Francisco to Gilroy, only had enough funds to convert about three-quarters of their trains to electric multiple units.

On April 26, the board was informed it would receive a $164 million grant [see #13 of Project Detail Summary (pdf)] to convert the remaining 25 percent of diesel-locomotive-hauled trains to zero-emissions EMUs. Unlike the Redlands train project, Caltrain uses mostly older locomotives, so the conversion will literally mean cleaner air for Peninsula residents, at least from trains.

Zachary Clark of the San Mateo Daily Journal reports on the Caltrain award, along with a $253 million grant for the San Mateo Highway 101 Managed Lanes project and $36 million grant for SamTrans to run an express bus pilot when the express lanes are constructed and operating, potentially in 2021.