InTransit Extra


Assessing Vehicle Power

As transit owners evaluate ways to gain greater efficiencies in their operations, many are exploring alternatives to how they power their vehicles. The good news is options exist and so it comes down to what is right for your agency now and in the future.

Diesel multiple units, hydrogen fuel cell testing, retrofitting older vehicles with batteries and alternative vehicle power are some of the options. Click the icon below for a brief overview.



Finding a point of entry

How does an agency enter this new space? Is proven, cost-effective electrification the best route? Should you wait for battery or hydrogen fuel cell technology to mature? Or, given the infancy of some technologies, would it be less risky to procure cleaner-burning diesel engines to replenish aging inventory? The following steps can help decision-makers assess which course of action is best:


1. Conduct an inventory assessment. Knowing a fleet’s age and the number of years an agency can extend service life with proper maintenance will begin to clarify how long the agency can wait for alternative technologies to mature.

2. Perform a cost-benefit analysis – and factor in the soft costs. Capital costs and long-term operating and maintenance expenses are critical to making a sound decision. But today’s cost-benefit analysis also must factor in environmental impact and social equity. Considering those soft costs in the equation is increasingly important. Although the numbers may show converting to an all-electric fleet would be cost-prohibitive, for example, soft costs may warrant it.

3. Set a goal and start planning now. Goals to electrify a fleet by 2050 or produce zero emissions by 2040 are admirable but unrealistic unless they are backed by an aggressive, forward-thinking implementation plan. To be successful, owners may want to consider decommissioning revenue service diesel locomotives early.

The California Air Resources Board realized retiring perfectly good rolling stock doesn’t pencil out without financial incentive. So, CARB is paying agencies to sell their fossil fuel- powered locomotives. The idea being agencies can’t reach these lofty goals by themselves. It may require a team of local, state and federal agencies, incentives and/or programs to help make them happen.

We also will not see agencies doing wholesale swap-outs of existing assets. Instead, a likelier strategy is incremental adoption, resulting in a mixed fleet of fossil fuel-, battery- and hydrogen-powered vehicles. Managing a mixed fleet won’t be easy, but it is more realistic.

In short, before announcing a moon-shot goal of eliminating harmful emissions, make sure it is realistic, achievable and in motion.

4. Begin R&D. A robust R&D program can help determine the type of alternative power, if any, to approve, but instituting such a program is a heavy lift for public agencies. Researching alternative vehicle power is new territory best navigated with the assistance of an experienced consultant.

The right consultant can help:

• Identify the best type(s) of alternative power• Interface with vehicle manufacturers
• Plan service and systems components
• Conduct grade crossing analyses
• Design and/or retrofit stations, grade crossings and maintenance facilities • Coordinate with other agencies if sharing track
• Perform the required civil work for traffic signals and warning devices


The bottom line

There is a tremendous amount of information to gather and process when considering alternative vehicle power. For transit and commuter rail agencies considering emissions- friendly or zero-emissions vehicles, there is no clear winner – and there won’t be. The path forward will depend on each agency’s specific goals and circumstances. What is best for one system may not be right for another. But one thing is certain: Alternative vehicle power is coming to the U.S. market, and with it comes a host of new opportunities for greener, more efficient transit systems.



Graham Christie, PE,

Patrick Allen, PE,