Over the years, Toyota has made quite a buzz for its alternative energy ideas, and forward-thinking fueling goals. Does anyone recall that hydrogen-powered 5.0-liter V8 RC-F engine that Toyota commissioned a couple of years back? Yeah, pretty forward-thinking stuff indeed.

But hydrogen engines and (yawn) hybrid motors aren’t the only things that Toyota is dabbling in. As more and more people discover that their EV batteries are far worse for the environment and human health than automakers would have you know, alternative fuels have quickly become the hot topic of discussion.

Take all of the buzz surrounding that engine that Toyota built in collaboration with Chinese automaker GAC Motor. Apparently, this thing is designed to slurp on ammonia and produce power without any carbon dioxide emissions from the tailpipe.

But while there is a ton of talk about Toyota cannibalizing its EV sales with a project of this caliber, the topic of using ammonia as a viable fuel source for internal combustion engines is far more fascinating to us over here at EngineLabs.

After all, isn’t ammonia extremely dangerous and quite detrimental to the environment when converted to a liquid form?

Ammonia is made up of one Nitrogen molecule and three Hydrogen molecules.

Break Out Your Pocket Protectors Kids… It’s Science Time!

One part nitrogen atom, and three parts hydrogen atom, good ol’ Uncle Ammonia has long retained his spot within the “NH₃” slot in the scientific table. Molecularly speaking, he’s really not that bad of a dude either at first glance.

Being that there really aren’t any carbon atoms present, CO₂ production levels from burning ammonia seem about as low as you can go. But start to consider the energy and equipment required to make the stuff viable as a source of fuel for a combustion engine, and you’ve got a fat batch of fresh variables to consider.

Much like Toyota Denso’s “microalgae biofuel project” from a few years back (which we haven’t heard much about since 2015), ammonia requires an insane amount of power to be converted into a viable source of fuel.

Sure, you could convert the hydrogen atoms within the ammonia into a fuel cell source to produce electricity. But that would entail Toyota and GAC popping a fresh teet into the mouth of a rapidly growing EV toddler that they just swore to ween.

This leaves us with the most likely, and “easily” obtainable option: Give ol’ Uncle Ammonia a strong cocktail mix, and hope that he has the power to stand on his own when it’s all said and done.

Ammonia as a motor vehicle fuel would require a significant change to current infrastructures, both in ammonia production and fuel storage and transportation. Photo Credit: ChargeDrive/YouTube

Ammonia Spiked Hunch-Punch Anyone?

This fueling advancement may sound like breaking news, but according to the Ammonia Energy Association, Toyota has been dabbling in ammonia alternative fueling options for quite some time. Hell, last we checked the corrosive chemical compound was still being used alongside an organic slurry pulled straight from the surrounding farmlands to produce power for Toyota City just outside of Nagoya. (And yes, Toyota built a city in Japan and named it after itself. We like this idea. “EngineLabs Avenue” has a nice ring to it, don’t you think?)

Being that this chemical compound can feasibly be cut with diesel, gasoline, or even hydrogen to make an ammonia “hunch-punch,” GAC says the prototype engine that it developed in partnership with Toyota can indeed be powered by liquidized NH₃. A technology that up until now has been reserved for ships, freight trucks, and farm equipment.

So to see a claim that a 2.0-liter 4-cylinder can produce 161 horsepower on this stuff, with a 90-percent reduction in carbon emissions over pump gas is intriguing. For if put into production, this could become the first ammonia-powered passenger car in history to hit the highway.

2.0L Ammonia Engine. Photo Credit: GAC

We’ve overcome the pain point of ammonia being difficult to burn quickly and put the fuel to use in the passenger-car industry. Its value to society and for commercial uses are worth anticipating. — Qi Hongzhong, GAC R&D Center Engineer

GAC further explains that to make its ammonia engine clean enough to use, it had to cut nitrogen emissions, which was achieved, in part, thanks to an increase in combustion pressure. And while the automaker admits that the slow-burning fuel possesses about half of the energy density of gasoline on a per-gallon basis, it is the combustion of liquid ammonia that warrants the most interest. If combusted properly, liquid ammonia has the potential of being completely carbon, hydrocarbon, CO₂, and particulate emission-free. 

 The Ugly Side of Ammonia

So while Toyota’s new ammonia engine collab project with GAC does have some interesting merits that warrant a quick mention, we have just as many questions and concerns.

First of all, is the fact that ammonia tends to carry more toxic warning labels than a container of electric nacho cheese at a truck stop. So anything fuel system maintenance or upgrade oriented in an automobile would be extremely tricky to safely and inexpensively orchestrate.

Then there’s the fact that these engines will release a mess-load of nitrogen into the atmosphere if they don’t maintain sufficient levels of high compression or boost. So an improperly tuned, or misfiring ammonia motor could potentially be quite harmful, as this would lead to even more ammonia and ozone being released into the atmosphere. Acid rain, respiratory illnesses in children and elderly, birth defects… You name it, this stuff has the power to cause it when improperly combusted.

The vast majority of the world’s ammonia is used in the agriculture sector as a form of fertilizer. The remainder is commonly used as a refrigerant gas, or in the manufacturing of plastics, textiles, explosives, and pesticides. Photo Credit: ChargeDrive/YouTube

And then there is the substance itself, which is downright dangerous, both in regard to its natural state and manufacturing. It’s not like we can just pump ammonia out of the earth like crude either. The thermodynamic energy alone that would be required to convert liquid ammonia into a large-scale viable fuel source would completely negate the environmental benefits that Toyota and GAC are so quick to pitch to the public.

There’s also the underlying concern of infrastructure. To get ammonia fuel into these engines in the first place, you are going to need a hell of a lot of fueling stations that can safely and effectively store and distribute the substance. You’ll also need to get the ammonia to the pump somehow, which is a little scary to think about if you consider the number of tanker trucks and trains that would be rolling around with this toxic chemical inside.

And while ammonia is typically stored similarly to propane, its exposure to the human body is far more dangerous than say gasoline or diesel. Sure, it won’t combust like petroleum-based fuels, but holy hell is it corrosive and downright dangerous for the eyes and lungs. So we can’t (and don’t want to) imagine what a car crash between a couple of ammonia-powered cars would look like for all parties involved…