The Hardest Part of Electric School Buses, Made Easier

With the EPA’s Clean School Bus Program investing five billion in five years in clean school buses, almost all of them electric so far, it’s easy to focus just on the electric school buses (ESBs) themselves. They’re big, photogenic, quiet, and emit no bad smells. They command the floor space of the shows we go to like kings and queens. We all know that Ride and Drive events – experiencing ESBs in person — win hearts and minds, from drivers and mechanics to transportation directors and superintendents. ESBs are so charismatic, you could write a monthly newsletter about them (which I do, by the way).

Yet ESBs are useless by themselves. They depend completely on charging infrastructure. And getting your charging right is the hardest part of ESBs, not the waiting for the buses to arrive after you order them. (Though the waiting is hard, too; Tom Petty’s song is partly accurate.)

This article includes:

• The least a school bus fleet needs to know about charging
• Pros and cons of Level 2 (AC) charging and DC/FC charging
• How to reduce charging costs
• Where the EPA’s Clean School Bus Program is falling down on deploying clean technology

The least you need to know about ESB charging:

• The utility serving your bus yard/charging location is, or will become, your ESB fuel supplier
• You don’t have a choice on what utility that is
• Meet with your utility early and often on your anticipated ESB charging needs
• You will choose who to buy your chargers from
• You will choose who installs your chargers (the utility has no obligation to install chargers)
• Installation may cost 2x the chargers, themselves
• You choose between Level 2 chargers (slower), DC/FC chargers (faster) or both
• You charge (fuel) ESBs daily, unlike every two or three days for diesel buses
• How far your charger is from the power source – the electric panel or the transformer – makes a difference (closer is better)
• Figure 1-2 years to plan and install your chargers. You want them in well before your ESBs arrive (the buses are useless without them)

While it’s easy to fuel an ESB by clicking the charger into place (I allow neighbor kids playing in my driveway to plug our Level 2 charger into our Nissan Leaf) the humbling truth is that it’s just as easy to forget to plug in an ESB. One idea is to make it a part of the mandatory post-trip inspection checklist.

Level 2 (AC) Charging pros

• Cheaper to purchase (about $6,000)
• Cheaper to install (about $12,000)
• Option of wall mount
• Less likely to incur demand charges (think: speeding tickets from your utility)
• Only pulls/needs 9.6 to 19.6 kilowatts (kW)
• For that reason, less likely to require a power upgrade
• Can get two fueling ports per charger

Level 2 (AC) Charging cons

• Less range (miles you can drive) per hour spent charging
• No future vehicle to grid (V2G) capability or revenue
• Cannot contribute to community resiliency in power outage
• Cannot charge (future) visiting ESBs in timely manner

DC/FC pros

• Fast charging (3-4 hours, less for top-off)
  Less range anxiety
  Direct/fast-charged ESBs may cover more of your routes
  Future vehicle to grid (V2G) revenue is an option
  Can charge (future) visiting ESBs in timely manner
  The fleets that have fast chargers tend to like them a lot
  Potential to provide community resiliency in power outages (by discharging power)

DC/FC cons

• Costly to buy (about $55,000 to $60,000)
  Costly to install
  Take up more space in bus yard than Level 2 chargers
  More likely to incur demand charges from your utility
  Fast charging may shorten battery life
  Just one port per charger, unlike Level 2

Which to choose? Level 2 (slower, lower cost) charging will work fine for the majority of a school bus fleet’s routes (CTE). That said, it’s a best practice to get at least one DC/FC (faster, more costly) charger if at all possible, so you can fuel quickly when you need to.

How to afford a fast charger, especially when EPA rebate winners get just $20,000 for charging per ESB? Sourcewell membership can cut costs. Tim Farquer, Superintendent of Williamsfield Schools in Illinois reports on his charger purchases through Sourcewell: $4500 per NUVVE Level 2 charger; $46,030 per NUVVE 60kW V2G (vehicle to grid enabled) DCFC. Separately, Tim has ordered a repowered school bus (diesel to electric), and is a driving force behind the Bus To Grid Initiative. Tim rocks, to state the obvious.

Finally, if you’re a rural district in the Pacific Northwest needing help buying chargers, drop me an email. You may be in Bonneville Environmental Foundation territory, which is offering charging grants.

Transformers carry and manage electrical load; they are owned and operated by utilities. For electric load to substantially increase, as when lots of ESBs start charging at a given location, transformers may need to be upgraded. That’s costly. EPA’s Clean School Bus Program doesn’t cover such utility upgrades. What they do cover is $20,000 per ESB charger (remember that the unit and installing it are two separate costs).

Where the EPA is falling down on deploying clean technology — Before I criticize the EPA, I’ll note that I worked in state government for almost 10 years. I have empathy for government workers. Criticizing program policy is easy, and changing policy is hard due to politics and bureaucracy. That said, I know the EPA can do better than it’s doing on equity.

Air quality should become a key prioritization criteria of EPA funding. Strangely, it’s nowhere in the Clean School Bus Program (CSBP) criteria, yet. Going into the second year of its five year program, EPA is administering CSBP funds as if districts/kids breathing the cleanest air in the nation need zero emissions school buses just as badly as districts/kids breathing the dirtiest air. In what universe is that assumption true, or just? Another study came out recently showing that air toxins cause children to fall behind in school (Washington Post). It’s essential that air quality become a factor in distributing ESB funds. In the same way that getting the charging right is pivotal to operating electric school buses, putting the electric school buses where they will clean up dirty air is pivotal to making good use of the federal government’s investment in this clean technology.

By Alison Wiley

Charging experts Amy Hillman, Eve DeCesaro, Zoheb Davar, Tim Farquer and Luke Whittemore all contributed to this article.

Alison Wiley has worked in low-carbon transportation since 2006, focusing on electric buses since 2016. She writes the Electric School Bus Newsletter, which is funded in part by the World Resources Institute’s Electric School Bus Initiative, and is a member of the nationwide, equity-focused Alliance For Electric School Buses.