Hybrid power: Locomotive booster provides muscle to more efficiently move trains

“As America begins to tread new surface transportation territory with high-speed rail, power for such will be via electricity – clean electricity,” as I opined in “CATS: Diesel-electric versus pure electric train operations – pros and cons.”

Now, almost two years later, these words, I still stick by them. But, what about for non-high-speed rail train applications: Will it be ditto? It could very well be.

One offering from Rail Propulsion Systems (RPS) is what is referred to as: the “Zero Emissions Booster Locomotive” concept or “ZEBL,” for short.

The ZEBL, a “B” locomotive (a locomotive but with no cab accommodations for housing an onboard crew), as its name implies, serves as a “booster” to the “A” locomotive (a locomotive with cab). The “A” unit can either be in the leading position (train locomotive said to be operating in the “pull” mode) or in the trailing position (train locomotive said to be operating in the “push” mode). The ZEBL provides auxiliary or supplemental power.

As explained in an email by RPS Principal Partner and Chief Executive Officer Ian Stewart, “When added to an existing train [most commonly in passenger (commuter rail) operations], it is used to slow the train to a stop to charge its energy storage system by a process called ‘dynamic braking’ which back-drives the traction motors, turning them into generators, creating a braking resistance and generating electricity (a function that locomotives already have). This stored electricity is then fed back to the ZEBL traction motors to augment the train’s acceleration.”

Stewart explained further that the booster and the “A” locomotive, though they could, need not be directly electrically connected, the company CEO adding the locomotive duo (the “A” locomotive with crew cab in conjunction with the “B” so-called “cab-less” locomotive), is termed a “rail coupled hybrid.”

So, in essence, the ZEBL generates its own electric power through “dynamic braking” braking action which is used to create additional traction for the train: there are now more powered axles (the lead locomotive’s plus the booster locomotive’s) as opposed that of the lead locomotive only meaning the booster provides more train-pulling muscle for the train.

And what this means is instead of one powered locomotive doing all of the work, the work is split between the pair and what this means is that lead locomotive (with its four powered axles) and company (the ZEBL with its four powered axles) are producing fewer emissions.

Added Stewart: The “ZEBL is a true ZERO emissions vehicle.”

By virtue of there being lower fuel consumption by the diesel locomotive overall, emissions are also lower, the two – diesel fuel consumption and produced emissions – being directly proportional, Stewart related.

Bottom line: A more efficient means of operating diesel-powered trains results.

More information on the ZEBL and other sustainable train operating platforms can be accessed at: www.railpropulsion.com.

– Alan Kandel