Transportation Troubleshooting: Before Buying Buses: Preparing for a Net Zero Fleet

“We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard.”

– President John F. Kennedy, Sept. 12, 1962

When President Kennedy famously made this declaration, many detractors scoffed at his ambitious goal as being unrealistic, misguided or unnecessary. But his vision motivated an age of space exploration and innovation that demonstrated what can be achieved when we “organize and measure the best of our energies and skills.”

I was reminded of these inspirational words when talking recently with my colleague Cliff Henke, senior director for Transit and Rail at WSP, about carbon reduction in transportation. Much like those early days of space exploration, ideas such as “net zero bus fleets” often are met with skepticism and dismissed as unrealistic or impractical. You know, too “hard.”

Few people are more qualified to discuss the complexities of transitioning to a net zero bus fleet than Henke. He’s on the frontlines, serving as the program manager for Los Angeles Metro’s trailblazing bus electrification project, which has set an ambitious goal of achieving a 100-percent zero-emissions bus (ZEB) fleet by the mid-2030s.

Let that sink in: Every single bus … in the second-largest U.S. city … within a decade. Now that is bold!

“It’s not just about buying the buses,” explains Henke. “As challenging as that can be with the technology in its current state and demand outpacing production, it’s still the easy part of the equation. Transitioning to a net zero fleet is dependent upon many huge macroscopic transformations that are also going on at the same time.”

Henke outlined many of those necessities, such as the following:

• Retrofitting existing depots to meet charging demands

• Constructing additional bus depots

• Staff training

• Planning for enhanced fire and safety

• Cyber security upgrades

• Creation of new bus routes that account for the current technological limitations of electric buses

“You really need to be thinking about facility modifications and choices before deciding what kind of buses you want to buy,” he adds. “That’s the critical path these program schedules must follow to be successful.”

Because of its outsized role in American culture and now because it will be hosting the Olympics in 2028, officials there know many eyes are squarely focused on the progress of LA Metro’s ZEB transition program. No pressure, right?

Route Reconfiguration

To meet the goal, new bus routes need to be modeled that consider limitations of the current technology. Traditional diesel or compressed natural gas buses can reach an average of 400 miles on a single tank of fuel, and Los Angeles bus routes are designed around the ability to travel that distance.

“Unfortunately, today’s battery buses can’t reach that range just yet,” notes Henke. “In practice, a realistic expectation in a city like Los Angeles is closer to 150 miles per charge.”

Overcoming that challenge requires identifying locations where electric buses can be charged during scheduled layovers—shortening routes without compromising performance. He said they’ve identified more than 50 viable opportunities throughout Los Angeles, but evaluations continue to ensure they find the most advantageous locations.

Resilience Chargers

Much of this technology is still in its infancy, and peak power requirements for an all-electric bus fleet—which could reach as many as 20 megawatts at each of its 13 bus depots—can initially exceed the current grid’s capacity where these depots are located.

What can be done until the power source matches the demand? What happens to the fleet when a power outage takes out the electric grid?

“We are installing what we’re calling ‘resilience chargers,’ which initially will provide temporary and backup power,” says Henke. “As the permanent infrastructure is developed, that same temporary system can then serve as reliable backup power in case the grid goes down.”

It might also require mitigation options such as generators or microgrids that are powered by natural gas or other sources.

“Not just for L.A., but for many of our other clients as well, we’ve done some design work on microgrids that also accommodate solar power,” he says. “While solar panels at a bus depot may only generate 2.4 megawatts of power, it could be enough to shave the peaks and deliver the load necessary to maintain sustainable operations.”

Success will depend on addressing how elements such as high or low temperatures impact the infrastructure. Suffice to say, if it works in a city where weather extremes and power outages are not uncommon, other U.S. cities will have a successful template to follow.

We’re at a critical point in our quest to achieve net zero—not just for buses, but for all transportation. Some may see that as an impossible task and suggest we aim our expectations a bit lower.

But President Kennedy didn’t aspire to travel halfway to the moon. I don’t think we have to settle for less, provided that, in his words, it’s a challenge “we are willing to accept, one we are unwilling to postpone, and one which we intend to win.”