The Mirai Down the Street: A Case Study in Sustainability

One of the highlights of my last semester as an aerospace engineering student was a new class, Sustainable Aviation. Previously, this course was offered as a Special Topics class outside of the regular curriculum but it’s now part of the course catalog of electives in AE—and I think that’s great. Despite the current political climate in the US, sustainability is as much of a problem as ever and will continue to be, as humanity will have to grapple with issues of climate-changing pollution and resource usage into the indefinite future. And the longer we wait to address it, the more of a problem it will become; to put things in perspective, global mean surface temperature (GMST) averaged over the last three years has already exceeded the 1.5°C limit agreed to in the Paris accords.
 
Even though the semester is over and I’m no longer a student, sustainability is still on my mind. And it turns out, I’ve found the perfect example of one of the major challenges of sustainability right here in my neighborhood.

No, not this one.

Defining Sustainability
 
In class last semester, we took as our starting point for a working definition of "sustainability" a specific passage in the UN’s Our Common Future, a monumental report by the World Commission on Environment and Development published in 1987. The commission met for three years and was tasked with identifying goals and strategies to achieve a sustainable future in the year 2000 and beyond. They defined sustainable development as,
 
"Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs."
 
The commission went on to stipulate that "needs" should not just encompass but give "overriding priority" to "the essential needs of the world’s poor," thus espousing a position of global equity as a necessary component of a sustainable future.
 
Multiple times over the course of the semester, we were asked to formulate our own definitions of sustainability in assignments and group projects. I took the Commission’s definition a step further, pointing out the impossibility of designing an indefinitely sustainable future; rather, we can work toward a more sustainable future than what we have now.
 
As I’ve given it some thought in the weeks since the semester ended, however, I think none of those capture the essential aspects of sustainability in the context of modern society and the various stakeholders involved in daily life, as well as being too vague: what are "needs" exactly? How do we distinguish between "needs" and "wants"? How do we know what future generations will "need"? I decided that what we need is a definition of sustainability that is specific and exigent. That got me thinking about what I can control in my own life and choices and everyday decisions that could be made more or less sustainable, and I realized that these are constrained by societal factors which are controlled overwhelmingly by government policy—local, state, national, and global—and corporations. For example, I can go to the grocery store and choose to buy fruit that was perhaps grown locally rather than trucked in from California, but its availability and associated climate impacts depend on a corporate choice over which I have no control. Maybe I can decide to get my produce at a farmer’s market instead, but that depends on local government scheduling and support (I can’t right now, because our local farmer’s market runs only though October before shutting down for the winter).
 
So, to put all that in one definition: Sustainability is the combination of individual choice and systemic change (forced by trends in individual choice and public/government policy) that results in the smallest "in" and "out" streams for every individual, government entity, and corporation and the least change to land, oceans, waterways, the atmosphere, the larger environment, and ecosystems from local to global scale, such that the best chance of preserving these things for the support of future generations and all forms of life on Earth is achieved.
 
I’m thinking of this as a "circles" model. I can control my own circle, choosing more or less sustainable options in my choices of food, goods, transportation, etc. My choices are constrained by the actions of corporations and government—the other circles—but I and other consumers have some influence in turn on those actions.
 
Measuring Sustainability
 
So, if I can only control my own choices in structuring my life more sustainably, it begs the question: how sustainable is it now? Since this is a blog about cars, let’s look at my choice of transportation and see if we can determine how sustainable it is.
 
In Sustainable Aviation last semester, we used a software tool developed by Argonne National Laboratory called GREET ("Greenhouse gases, Regulated Emissions, and Energy use in Technologies") to estimate the emissions impact of various energy sources and transmission pathways for vehicle life cycle analysis. GREET relies on a huge amount of data to estimate climate and resource impacts and allows for a high degree of customization to "tweak" these pathways and see what effect that has on the sustainability of a transportation system or vehicle.
 
After we were introduced to this tool and used it on a homework assignment, I decided to play around with it some more to try and answer a question that has been on my mind for some time: should I switch to driving an EV? I used GREET to model the upstream (well-to-tank, or emissions associated with producing and transporting or transmitting the fuel) and downstream (tank-to-wheels, or "direct" emissions produced by the vehicle's consumption of energy) emissions for my gas-powered hybrid car, a PHEV (Prius Plug-In Hybrid), and a popular EV (Hyundai Ioniq 5). Then, I compared the outputs of the model with data estimated by the EPA’s website calculator per mile and over a year’s worth of driving (15,000 miles):
 

	2013 Toyota Prius	2025 Toyota Prius Plug-In	2025 Hyundai Ioniq 5
GHG-100 GREET (g/mi)	218	205	218
GHG-100 EPA (g/mi)	222	202	218
GHG-100 GREET (kg/year)	3,267	3,068	3,270
GHG-100 EPA (kg/year)	3,330	3,030	3,270

 
Both models agree closely, and both suggest the same outcome. Assuming I plug the PHEV or EV into grid power here in the Midwest, the answer is clear: there is essentially no difference in terms of emissions between either of these choices and the car I have now. When we take into consideration the increased impact from the large battery in both of these (13.1 kWh in the Prius, 63 kWh in the smallest Ioniq 5), then the plug-in cars are objectively worse than simply keeping the car I have now, which has a much smaller and less resource-intensive 1.3 kWh NiMH battery (which, at 12 years old, is still going strong). Either way, the upstream and direct emissions impact of my driving is significant, at more than 3 tonnes per year with my usual yearly mileage—and I have no easy way to improve on that, even if I buy a "clean" EV.
 
So, if my choice between an economical BEV or my current gas hybrid makes no real difference in terms of my sustainability impact due to transportation, are there any better options? Leaving aside the question of forgoing a car entirely or utilizing public transportation more often, the answer is still "yes." If I install a solar array, for instance, this could reduce my GHG impact from electricity generation—but since I live in a condo, and one that is nicely shaded by large oak and maple trees, putting up a solar array isn’t really feasible for me right now. As far as other options, hydrogen power, especially "blue" hydrogen (made from water using PEM electrolysis), is much cleaner than either gasoline or grid power electricity when produced using solar power. And it is already being used in my community to power local transit district buses. Could I utilize something similar for my personal transportation?
 
The Mirai Down the Street
 
Back in April, I was very surprised to see, at a used car dealership I passed regularly on my way to school, a new car suddenly appear on their lot. I did a double-take at first because I almost couldn’t believe my eyes: it was a first-generation Toyota Mirai, here in central Illinois—thousands of miles from the nearest public hydrogen station.

Several months later, the Mirai still on their lot, I stopped in to ask about it. Someone had moved here from California and traded it in, the salesman said; they had gotten a few test drives out of it before it ran out of fuel and there it has sat ever since. They were desperate to get rid of it, too. I hadn’t been there more than half a minute before he asked if I wanted to make an offer on it.

Mirai’s don’t hold much value, even in California, so I would have made an offer in a heartbeat if I had a source of compressed hydrogen. There’s the rub: if I bought this thing, I would have no way of fueling it. There is no infrastructural support for compressed hydrogen fuel in my community; I can buy compressed hydrogen cylinders online but they'll have to be trucked here (with associated diesel combustion emissions) and I would still need some sort of adapter to get them into the car's tank which, as far as I'm aware, does not exist. Were I to buy this Mirai it would sit in my garage, just as much a brick there as on the dealer lot. Here’s a piece of automotive history, one of the rarest cars in the US, which I would happily put to good use while reducing my carbon footprint drastically…and I can’t. As an individual, I’m completely ready to buy in but, because corporations and government are not, I am stymied.
 
Well, some corporations. Toyota (along with Honda and Hyundai) has obviously gone in on hydrogen, devoting the engineering resources and development costs to create not one but two generations of Mirai. A handful of other companies, like Shell and TrueZero, have built hydrogen stations but only in California. And our federal government is currently antagonistic toward hydrogen and other alternative fuels, cutting off a major grant to develop hydrogen infrastructure in the Pacific Northwest just a few months ago.
 
In the face of that, my willingness to adapt and good intentions are worthless insofar as they amount to no real sustainability impact. The frustrating thing is, this is through no fault of my own and despite the fact that one of the largest automobile manufacturers in the world has already developed the product and it is available to me to purchase. How aggravating is that?
 
Perhaps even more aggravating is the fact that it doesn’t have to be this way. If we collectively decided to make hydrogen infrastructure work, we could do it—with enough government funding for research and development, enough corporate buy-in to build out infrastructure and products, and enough consumer support to buy and utilize those products. Such a hydrogen economy would be no more complex than the fossil fuel system and all its supporting infrastructure we have now; the only difference is, we’ve spent the last century and more building that out while hydrogen has had no such head start. Now, no one wants to jump first and we’re largely stuck with what we have.
 
We’re All in This Together
 
The challenge of sustainability lies in its pervasiveness: no one person or entity can solve it on their own. All of us have to work together to recognize that we have a problem, that this problem has exigent demands if we are to address it let alone solve it, and that we are currently failing to do so in any meaningful way.
 
I wish I had something more hopeful to offer to finish out this post, but I really don’t. Politically in the US, we’re working backwards now. Corporations are largely following suit, trying to maintain favor with the administration and following market changes in things like projected future EV demand. What I can do is try and structure my life and personal choices to be as sustainable as possible in the context of all that, and in that light, I’m going to try making some changes this year. I’ll write about those in future posts if I feel like it. Until then, keep your stick on the ice.