School buses are ripe for electrification. First off, they replace dirty diesel with clean electrons, which dramatically reduces emissions of both CO2 as well as other harmful pollutants like air particulates and NOx. Since a majority of low-income children (60%) ride the bus to school and school buses with lower emissions have been shown to result in higher test scores for the children who ride them, this has major implications on bringing the benefits of electrification to underserved communities.
School buses also run relatively few miles and can charge between the morning school run and the afternoon run, so they don’t typically have range concerns. Electric school buses also have huge batteries that will sit idle most of the summer and could be used to store energy and then help balance the grid during peak demand, which could potentially earn money for cash strapped school districts. Finally, the Biden administration, as part of its infrastructure package, is putting forth a plan to replace ⅕ of our hundreds of thousands of diesel school buses with electric.
But even with all these stars aligning for this industry, there are still significant challenges to widespread adoption, with cost being the top barrier. I sat down with Trevor Rudderham, Senior Vice President of Product Planning and Electrification from school bus maker Blue Bird, to talk about electric school buses, all the ways communities can use them, and how fast the industry is headed towards electrification.
Trevor, there are something like 480,000 school buses in the US, and electric school buses are still such a small portion at close to 1,000. Given these numbers, how fast do you see the switch from diesel to electric occurring?
I think the total number of school buses is actually a little more than 480,000. At Blue Bird, for example, we’ve got 180,000 school buses that are currently in operation.
As for how fast things will change, there are bulls and bears. Pre-COVID, the type C+D school bus turnover rate was in the range of 30–35k buses annually. I personally (and I do emphasize personally) think that by 2025, if the Biden administration’s initiatives are passed, at least 40% of the school bus market will be electric. The Biden administration is saying it wants to electrify 20% of the school bus fleet over the next 8 years. I think that is awesome! There will be some ramp up time as capacity is put in place, so beyond 2025, that 40% will grow significantly. I won’t put a date on it, but it won’t be too long after that before all new school buses will be electric.
As of today, Blue Bird has capacity to build about 1,000 EV type C+D buses per year, but we are already looking to meaningfully increase that.
The sticker shock of electric school buses is a barrier to their adoption. They can cost between $300,000 to $400,000 while their diesel counterparts cost less than half that, $125,000—$175,000. As battery prices come down, do you see the cost of ESBs coming down as well?
The end customer does not usually pay the full price of the bus. I would hazard to guess that probably 90% of everything we’ve sold to date has grant funding behind it. California is almost exclusively grant funded.
The other thing is that the highest proportion of the cost difference between a fossil fuel bus and an electric bus is the battery. The rest of the EV system is actually very comparable. So if you took the batteries off the bus, the cost is very similar to a fossil fuel bus and over time it’s probably going to fall below that.
So the price difference really is attributable to the batteries. A recent Bloomberg article pointed out that 10 years ago, batteries were about $1000 per kWh. In the automotive world, Teslas and the like, their volumes are astronomical compared to what we’re doing at Blue Bird (we’re literally talking a thousand times as many electric vehicles as us). They’ve got huge economies of scale and purchasing power and they’re talking about getting close to or even below $100 per kWh As more people adopt EV, that should help drive everyone’s cost down. That will lead to lower prices for the end customer.
Our buses have 155 kWh of batteries on it. When you look at a typical school bus, you’re looking at 12,000 miles a year, and 180 school days a year: that’s about 66 miles a day, 33 in the morning, 33 in the afternoon. If you’ve got a mid-day opportunity charge given the bus is stationary for four, five, six hours during the day, you’re really only looking at a range requirement of 40–50 miles with an opportunity charge or 80–100 miles without. 150 kWh is going to cover about 80–90% of the true range requirements of the users of electric school buses.
If you say that, in the not too distant future (and again I’m not quoting prices for what we pay), let’s just throw a number out there. Let’s say the battery cost is $200 a kWh. That means you’re now looking at $30,000 of total battery cost.
If you’re at the point where everything else matches a fossil fuel bus and you’re just having to buy batteries on top of that, you’re talking about a $30,000 cost difference — over a fossil fuel bus that is priced at, say, $110,000—$120,000.
That’s incredibly cheaper than the price of an electric school bus today.
Well, you’ve got infrastructure as well, like DC fast charging. And I don’t believe anyone in our industry is at $200 a kWh yet, but it’s certainly in the very foreseeable future getting to those kind of numbers. Now you’re at the point where if you look at total life cycle costs given that the operating costs, forget the electricity for a moment, a significant portion of the cost of any commercial vehicle including school buses is the maintenance; you’ve got fluid changes, oil changes, and then you’ve got brakes. Particularly in school buses in a stop-go environment. With regenerative braking, you typically can reduce your brake wear by 5–10× — now you’re talking about a very significant drop in cost of ownership per year.
Add on top of that, the (electric) fuel costs can be between a fifth to a third of the costs of diesel and you start looking at total lifecycle costs even without Vehicle to Grid, or V2G revenue, and you’re beginning to get to the point where electric school buses actually have lower total lifecycle costs than fossil fuel buses.
A lot of people are excited about the vehicle-to-grid (V2G) capabilities of electric school buses. As you said, these school buses sit there 180 days a year. What are your current thoughts on V2G? Blue Bird buses are V2G capable, correct?
Every bus we now ship is V2G capable. In fact, we just recently announced our first commercial deployment of V2G for a school district in Pekin, Illinois. If someone is willing to invest in the ground base infrastructure, our buses are capable of doing V2G with Nuvve as our partner. I don’t know if you’re familiar with ISO15.11.8-20 which is going to be an open source standard protocol for V2G communication from bus to charger. That has not been published, so right now there is no standard communication protocol for V2G from bus to charger or any vehicle to charger. So we’re using Nuvve’s proprietary communication approach and we are ready to go with that. So anyone who can put the ground infrastructure with Nuvve’s help or with third party funding or by themselves, we will be able to enable that bus for V2G. Now when 15.11.8-20 is published, we’ll be able to put that open source, standard protocol on the bus and then we’re not dependent on Nuvve for the communications, but Nuvve will be our partner for the aggregation across a fleet of buses or multiple fleets of buses to has more opportunity to meet the needs of the local utility.
I think it’s a huge opportunity. I think that the biggest single challenge to it is that right now it really only makes sense if you’re doing DC fast charging.
Again, if you’ve got a fleet of 50 buses, if you think about the total amount of energy you can bid back into the grid with that, it’s a big amount, it’s well over half a megawatt hour and that’s a lot of energy. If you think about the energy that is available and how much is the grid really going to be demanding — you can basically spend the entire night shuffling energy to and from the bus and that adds up to a lot of energy. If you can bid into the grid services market with a large fleet of electric school buses, I think you’ve got an opportunity to make significant money and, by the way, you can get paid even if you don’t send electrons back to the grid if you’re making the buses available for frequency regulation. The utility will pay just for the opportunity to access the energy, even if they don’t actually do so.
What do you think about the idea of electric school buses as a battery on wheels that can be used in an emergency when the power goes out?
The big open issue for resiliency, when you’re talking about a school or a hospital or something like that, is that the building has to have the ability to do what we call V2X — vehicle to building, vehicle to business, vehicle to school, whatever it happens to be.
I don’t think that’s a huge challenge: in fact, because you don’t have the interoperability agreement with the utility, being able to provide energy to, say, a hospital, in some ways that’s a shorter path. We’ve been talking about that for a long time.
Take cell towers, for example. Being able to maintain communications in a natural disaster is crucial and being able to drive a school bus up to a cell tower and either charge the towers if they’re discharged or simply be an energy source to them and allowing critical communication to continue could literally be a lifesaver.
Here’s another one — hurricanes. When people try to evacuate from a hurricane, in a lot of cases, there is no electricity to pump the fuel. You could drive a school bus up to a gas station and give people the ability to pump gas. We’ve given a lot of thought to this. People talk about electric cars and think that there will be vehicle to grid, vehicle to building, etc. in a disaster situation, but how do you coordinate all that? When you’re talking about school buses, you’ve generally got large school districts with a lot of buses; they are centrally controlled; you’ve got a natural disaster or power outage or whatever it happens to be, one phone call you can say to a school district “please deploy your 10 electric school buses where we’ve got a power outage.” Trying to do that with individual personal mobility is just not going to happen.
There isn’t another fleet where you have access to such a large pool of electricity. And that is something again which makes the electric school bus a very interesting proposition. Getting that message out is going to drive a lot of interest in electric school buses.