I think I’ve got the vapors…

Recently, Toyota has announced the death of the EV.

Corrosion Of Conformity: Toyota Takes Aim At EVs With Ammonia Engine

I was sad to hear about this, given all I’ve invested into the electric vehicle world. But, is there any truth to this assertion? Will ammonia fueled vehicles make EVs extinct? I have some doubts. Toyota has long been the buggy whip manufacturer that says cars will never catch on. Turns out, when your big market is internal combustion engine parts, everything looks flammable. Apparently, even ammonia. That is to say, Japanese automakers are a bit enamored with gasoline engines because so many Japanese companies happen to make gasoline engine parts. Coincidence?

If you are anything like me, the flammability of ammonia was not something you will have ever heard about. Ammonia burns?! I had no idea, I thought it just cleaned floors and windows. Well, it sure burns when you breathe in it. But, combusts?! Yes, apparently it can combust. However, the big take away from this discussion is this: it has half the power per gallon of gasoline and combusts more slowly. That… doesn’t seem like a good thing for an engine. Usually when discussing a new fuel, the phrases “doesn’t burn as well” and “doesn’t have very much energy per gallon” are not things you want to hear. In contrast, diesel “doesn’t burn as well” but has more energy per gallon than gasoline. Usually that’s the sort of trade off you want to see. Maybe it’s harder to burn but it yields lots of energy when it does.

Also covered in the above article is something most people probably at least have some intuitive sense of – ammonia is nasty stuff. I find myself very rarely popping the top off of a gallon of ammonia and inhaling deeply. Sure, it clears the lungs but not in a particularly pleasant fashion. This beautiful smell is generally courtesy of household ammonia which is 5-10% ammonia and then the rest is mostly water. We’re not talking about using 6% ammonia for an engine. This would be either 100% ammonia or some ratio of ammonia to diesel/gasoline. Either way, imagine what coming into contact with nearly pure ammonia will do to you. Now, I don’t generally bathe in gasoline but I do have some experience in being sprayed with both gasoline and diesel. Neither one can be used as a cologne but you’ll be OK if they spill on you – so long as nobody was smoking in the vicinity or heavily dragging their feet across the carpeting. You wipe it off then you smell like fuel for the next day or two. But, you live and aren’t too much worse for wear. In fact, I have more than once cleaned tar off my hands with gasoline. Gasoline is a wonderful solvent for many sticky substances. Not so with pure ammonia. You will be in bad shape if a gallon of ammonia spills on you.

Another aspect of this discussion is the availability of the substance. Ammonia is half as energy dense as gasoline so you would need twice as much of it. The US uses 135 billion gallons of gasoline per year. Gasoline weighs about 6 pounds per gallon (sorry readers in reasonable countries that use metric). That’s 810 billion pounds or 405 million tons of gasoline. The current global ammonia production is 176 million tons. You might see a bit of a discrepancy here. Presumably they aren’t splashing around in pools of the stuff and it is all being used somewhere. So, we would need to go from 176 million to (176 + 405 * 2) = 986 million tons to totally supplant gasoline. That seems like a rather large increase. The only upside is that ammonia is nothing but nitrogen and hydrogen and there is a large amount of both on Earth. But, we do not have an economically viable or energy efficient way to make that much ammonia. Also, there are no ammonia gas stations yet. Toyota seems to be advocating for building an entirely new infrastructure for fueling for a fuel that kills you if it escapes, smells AWFUL, is not that energy dense, doesn’t burn well, and when it does burn is prone to creating nasty nitrogen compounds that cause acid rain. Where do we sign up?!

But, can’t many of the same arguments be used for EVs? There aren’t nearly as many EV charging stations as there are gas stations! Or, are there? It turns out, you can charge your EV at home. Mr. Clean isn’t going to go in your car’s ammonia tank if you run out of fuel at home. EVs can be charged nearly anywhere as electricity is ubiquitous. Another advantage EVs have is the ability to charge on renewable energy. Technically, I suppose ammonia could be made somewhat renewably too with solar and wind.

https://royalsociety.org/topics-policy/projects/low-carbon-energy-programme/green-ammonia/

But, which is more energy efficient, charging an EV battery or converting water into hydrogen, filtering nitrogen out of the air, and combining the two with a ton of energy? Anyone want to guess?

Of course, it is commonly brought up that lithium doesn’t grow on trees and we currently have no means to get enough lithium, cobalt, and other elements to make enough batteries to go 100% EV. Popular Mechanics has an article about this very topic: https://www.popularmechanics.com/science/energy/a42417327/lithium-supply-batteries-electric-vehicles/

But, battery technology is both MUCH farther along and widely supported than ammonia engines and more adaptable. Maybe lithium is in short supply. But, we can make sodium batteries. Sodium is found… everywhere. There are likely trillions of tons of sodium in the oceans of the world. For a long time we used nickel metal hydride batteries. In the past we used lead acid batteries. Fundamentally an EV does not care where the electrons come from. Tomorrow we could switch to sodium batteries and the cars would be just the same. There are many more options in the EV world than there are in the “maybe we can force internal combustion engines to keep going so we can keep making pistons” world. So, am I worried about the brags and boasts from the likes of Toyota? No.