Figuring out how much power your agency will need is an issue that can be solved by working with a consultant or supplier. - Photo: SDMTS

Figuring out how much power your agency will need is an issue that can be solved by working with a consultant or supplier.

Photo: SDMTS

With a focus on being better environmental stewards, transit agencies around the nation are not only looking at but also beginning to transition to a fully zero-emissions fleet.

Before those vehicles can be added to their fleets, though, it is necessary to implement a plan to both house and charge or fuel the vehicles. 

Detailing a Zero-Emission Transition Plan

Recently, the Bipartisan Infrastructure Law amended the statutory provisions for the Grants for Buses and Bus Facilities Competitive Program and the Low or No Emission Program to include a requirement that any application for projects related to zero-emission vehicles include a Zero-Emission Transition Plan.

As defined in statute, a Zero-Emission Transition Plan must: 

  • Demonstrate a long-term fleet management plan with a strategy for how the applicant intends to use the current request for resources and future acquisitions.
  • Address the availability of current and future resources to meet costs for the transition and implementation.
  • Consider policy and legislation impacting relevant technologies.
  • Include an evaluation of existing and future facilities and their relationship to the technology transition.
  • Describe the partnership of the applicant with the utility or alternative fuel provider.

Examine the impact of the transition on the applicant's current workforce by identifying skill gaps, training needs, and retraining needs of the existing workers of the applicant to operate and maintain zero-emission vehicles and related infrastructure and avoid displacement of the existing workforce.

With these guidelines serving as a basis, METRO spoke to a panel of experts, including Alan Westenskow, director, business development, at Proterra; Mackenzie McGuffie, electric vehicle project manager, based in HDR’s Phoenix office; and John Drayton, national lead, zero-emission mobility, at Burns Engineering, to discuss some tips for developing and executing a Zero Emission Bus (ZEB) infrastructure plan.

Plan for Zero-Emission Buses Early

If you are a transit agency even thinking about adding ZEBs to your fleet, our experts say you should start the infrastructure planning process at the same time, or at least as early in the process as possible. 

“Ideally you want to start the infrastructure planning process as soon as you have some basic idea that you're planning to add an electric bus,” explains Westenskow. “Starting the process early will allow you to have the chargers and other infrastructure ready to go when your buses arrive.”

Planning early is also key if agencies have to adapt their current bus facilities. Our experts discussed situations where the agency’s current facilities weren’t large enough to house more buses and equipment and the decision had to be made to revamp the current facility or even look at building a new one. 

Paramount to the planning process is of course involving all key stakeholders inside the agency, as well as local officials, first responders, and more. Key to the planning process is involving your local utility to figure out how to get electricity to your facility to charge your buses. Our experts suggest engaging your utility at the very beginning of the process.

“Involving your public utility early and often is key to a successful ZEB deployment. They will be playing a large role in your infrastructure and fueling, and their support can determine where you can charge, how you can charge, and even how much your project will cost upfront and through the life of the electric buses,” says McGuffie. “Get them involved early so they understand the large power load that you are going to need in the years to come. Depending on the amount of power you need and the local grid, adding substantial new capacity can take years, so it’s important to make that need known as soon as possible.” 

“You really do have to reach out to your utility like yesterday,” adds Drayton. “We’ve run into situations where the utility needs several years to plan on how they can get the necessary energy to an agency’s facility, which could in essence push an electric bus program back significantly.”

Drayton is quick to point out that he is referring to zero-emission vehicles and not just electric buses. Therefore, if your agency is embarking on a hydrogen program, the planning is similar in that you should start early to identify how much and what type of hydrogen fuel your agency plans on moving forward with. In the case of hydrogen, you are also looking at having the space necessary to install an actual fueling station onsite, or perhaps nearby. 

“Hydrogen has a different set of factors that need to be addressed, which need to be properly planned for in advance,” says Drayton. “For instance, where is the fueling site going to be located — are there building or structures adjacent? Do you have space to bring hydrogen onsite and what type of hydrogen are you hoping to use? The fundamental question for either electric or hydrogen is knowing where you are now and where it is you plan to get to in a particular timeframe.”

Key to the planning process is involving your local utility to figure out how to get electricity to your facility to charge your buses. - Photo: NREL

Key to the planning process is involving your local utility to figure out how to get electricity to your facility to charge your buses.

Photo: NREL

Do You Know Where You’re Going with Zero-Emissions?

On the subject of actually planning, it’s important to know both what your program is starting with and what your goals are as you get further down the road with ZEBs.

Figuring out how much power your agency will need is an issue that can be solved by working with a consultant or supplier. During a conversation, Westenskow was able to walk through some of the equations and factors he considers to help customers determine how much energy they will need to charge the buses they plan on housing at their facilities. 

“There are many moving pieces to the equation, but it’s important to figure out how much power you need so that you can communicate that need to your local utility,” Westenskow explains. “It’s one thing to call a utility and let them know that you are adding some electric buses. It’s a much better thing, though, to be able to call the utility and tell them you’re adding buses, and here’s how much power you will need. It can be a bit tricky, but by doing proper analysis it will help you be ahead of the curve.”

McGuffie adds it is important to have both a short- and long-term plan in place when adding ZEBs. She says it’s also important to build markers in your plan that will allow agencies to assess where they are currently versus where they are planning on going. 

“A near-term plan would ideally look at the next five to seven years, and a long-term plan would look at the time that it would take for your entire fleet today to be replaced with new vehicles. For most agencies, this timeframe is around 2040,” she says. “You can be a lot more detailed with your near-term plan, and once you are in the midst of enacting your near-term plan, you can start using this to inform your long-term plan. I encourage our partners to develop some markers to assess near-term plans and to develop interim goals to meet the long-term goal.” 

As for determining the number of chargers you need at your depot to charge your new buses, Drayton says as vehicle procurements get larger and charging technology continues to mature, it’s not necessarily a one charger per bus ratio as it may have been in the past.

“Charging technology is evolving quickly,” he says. “With that in mind, it’s important to plan while keeping some flexibility in case there is a solution that is more effective.”

In fact, there are charging solutions that can now power several vehicles at a time, including Proterra’s 1.44-megawatt charging system.

“It’s like having eight single chargers, so you can charge eight buses at 180 kilowatts or literally have 24 buses plugged in and charging at 60 kilowatts at the same time,” says Westenskow. “What this type of technology does for fleets is it gives them the flexibility to increase the utilization of their asset, which is really the key here. If you can manage the timing of when different vehicles in the fleet charge relative to when they are available to charge in the bus depot, you can install fewer chargers, improve your ratio of chargers to vehicles, and reduce overall cost.”

There are also other options to consider when planning to charge your buses outside of the bus depot, such as inductive, or opportunity chargers. The experts say there is a time and place for inductive chargers, such as bus stations where the buses sit a bit longer than usual. They have also been found to be beneficial in helping to extend range, and like traditional depot chargers, the technology is maturing rapidly. 

Ultimately, though, the decision to have conductive or inductive chargers, or both, is entirely up to the agency. 

“It can come down to an agency’s preference and what they’re most comfortable with,” McGuffie says. “As consultants, we can provide guidance and the pros and cons of each option, but it’s up to the bus owner to decide what they prefer. The good news is that there are multiple quality options with proven technology for both depot and opportunity charging.”

Final Thoughts on Zero-Emission Buses 

Of course, this is just a smattering of things to consider when adding zero-emission buses, or deciding to fully transition your fleet. There are also big hurdles to watch out for along the road, according to our experts.

“The biggest challenge is actually integrating it all together so that you’ve got the design, procurement, and installation all happening in a way that is going to get your agency what you need in a suitable time and at a price that is reasonable,” says Westenskow. “It can be tricky because oftentimes there a whole bunch of players involved. You can be working with different people for your buses, chargers, design work, engineering, and installation. If they aren’t all working together and communicating regularly, it can pose some real issues.”

Drayton adds the hurdles he sees agencies having to negotiate are “all over the map.”

“It really starts with proper planning and having checkpoints in place that ensure you are studying and answering all of the important high-level questions,” he says. “After that, we have found it works best when an agency purchases a purpose-built zero-emission bus from a qualified OEM. Lastly, I’d say a big hurdle is getting all of your equipment installed before that first vehicle arrives. You don’t want your buses sitting around while you are waiting to complete work at your facility.”

McGuffie explains from her perspective, a big hurdle agencies are currently facing are issues with range, making it difficult for them to replace vehicles on a one-for-one basis. She adds that she also sees some agencies moving forward with impatience, leading them to skip steps along the way.

“When agencies skip the research and long-term planning and jump straight into a project, it can lead to a piecemeal approach that requires more work and additional investments,” says McGuffie. “Agencies find themselves at the end of a pilot project, but unsure what to do next and unclear on how to translate their effort to a larger scale. This often happens as a result of projects that were designed to test technology or utilize an available funding source versus being a smaller strategic element of a strategic, community-focused roadmap. The solution, of course, is starting with a holistic, system-wide approach that has a clear end goal.”

About the author
Alex Roman

Alex Roman

Executive Editor

Alex Roman is Executive Editor of METRO Magazine — the only magazine serving the public transit and motorcoach industries for more than 100 years.

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