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Big Oil Will Ditch Fossil Fuels in Favor of Ammonia and Hydrogen, Not Batteries

Fossil fuels industry - you can’t live with it, and you can’t live without it. As we are slowly shifting to a hydrogen-based economy, it seems that lately, ammonia is the perfect answer to this hopeless ongoing conflict. At least this is what energy companies are saying.
Ammonia has a great potential for green H2 7 photos
Photo: Korea Shipbuilding & Offshore Engineering Co.
Different shades of HydrogenPrinciple of sourcing H2 from H2OAmmonia is much safer to store than hydrogenMass flows in the ammonia supply chainAmmonia is still challenging for enginesTransport of green energy using ammonia
Climate change is real, and the global warming caused by anthropogenic CO2 is real. If we don’t act now to stop man-made pollution, the threat to our survival on this planet is unquestionable. On the other hand, if we stop using fossil fuels now, our advanced society will simply collapse.

It’s a lose-lose scenario. Of course, that is the case if you agree with the scientific consensus. It may come as a surprise for most, but the fossil fuels industry does agree with science, finally. Moreover, Big Oil assumes part of the responsibility for the current situation.

And it bets on hydrogen as a replacement for polluting fossil fuels. In short, what they say is “we apologize for almost ruining us all, but, hey, we have the perfect cure!”

The problem of gray hydrogen

Hydrogen is the most abundant element in the Universe. It’s the fuel used by our Sun and when burned it doesn’t release carbon – because there are only two atoms of hydrogen in an H2 molecule. It really is the perfect replacement for oil.

Do you remember when electric cars were considered the perfect replacement for internal combustion engine cars? That was until someone pointed out that while they don't pollute when in use, battery manufacturing is responsible for a lot of pollution and GHG emissions. And also, electricity as well is sourced mainly from polluting coal power plants.

Thus, electric cars are plagued by related pollution problems, which coincidentally fits very well with the industry praising the hydrogen future. But let’s just apply the same principles of related pollution to how hydrogen is sourced nowadays.

Different shades of Hydrogen
Photo: IRENA
Most of it comes from natural gas reforming which consists of reacting natural gas with high-temperature steam, resulting in synthesis gas – a mixture of hydrogen, carbon monoxide, and carbon dioxide. Hydrogen is also obtained by the gasification of coal or biomass, which is converted into gaseous components with high-temperature steam and oxygen.

Basically, it all comes down to cracking the methane molecule (CH4), which consists of one atom of carbon and four of hydrogen. The cheapest and most common method is to use methane from fossil fuels. In the U.S. 95% of the hydrogen is sourced this way, that’s why it’s called gray hydrogen.

Related pollution of gray hydrogen is a serious problem. First of all, the extraction of natural gas is associated with uncontrolled methane emissions. These are estimated to be at least a quarter of the quantity of contained natural gas.

NASA is monitoring methane data from EMIT Instrument installed on International Space Station in July 2022. That’s because methane is more powerful than CO2 at trapping heat in the atmosphere and we risk accelerating global warming if we rely on natural gas.

Moreover, cracking methane requires very high temperatures and pressures. It’s an energy-intensive process, and it means burning a lot of fossil fuels. As a consequence, related pollution of gray hydrogen is much higher than that of battery manufacturing.

Best way to get green hydrogen

The most sustainable way to get green hydrogen is to split water (H2O). But separating the oxygen atom from the two hydrogen atoms requires much more energy than methane cracking. It can be done using electrolysis or high temperatures, but you need a lot of renewable power.

Principle of sourcing H2 from H2O
Photo: Image by macrovector on Freepik
There are other ways of sourcing green hydrogen, like the fermentation of sugar-rich feedstocks converted from biomass, using green algae to consume oxygen in the water and produce hydrogen as a byproduct, or reforming ethanol at high temperatures.

But they don’t have the same potential and efficiency, and the costs are very high. So, they are only marginal. The bottom line is green hydrogen is way more expensive than gray hydrogen for now. And is no match for the low costs of fossil fuels.

Well, things will change a little when we take into account the real costs of pollution. There has been a carbon tax in place for many years now, and it’s going to increase. But it can’t be increased ten or twentyfold overnight – it would simply crash the global economy, and it’s another dead-end.

That’s why analysts predict that large-scale economically feasible facilities for green hydrogen will be in place only around 2030. Mainly because of big investments into harnessing ammonia technologies.

The best hydrogen container

You can find all sorts of interesting facts about ammonia on Google and Wikipedia. Like the fact that it saved humanity from starving a hundred years ago. The Haber-Bosch process helped farmers all around the world increase crop production by replacing natural fertilizers with ammonia “turbo fertilizer”.

Today, ammonia is a $60 billion worldwide business per year, and more than 70% of it is used in agriculture. By 2050, it is estimated to reach a market size of more than $200 billion, because of growing demand in the energy and transport sectors. Some forecasts are pointing to a six-fold growth possible, from today’s production of 185 Mt annually to more than 1,000 Mt by the half of the century.

That’s because ammonia (NH3) is hailed as the best carrier for hydrogen energy. It has a nitrogen atom bonded to three hydrogen atoms and its energy density by volume is double that of liquid hydrogen. It’s simply an energy-rich gas that can easily be cooled and squeezed into liquid fuel, that can be shipped anywhere in the world and converted back into hydrogen.

Ammonia is much safer to store than hydrogen
Photo: PaxOcean
It sounds very similar to oil, doesn’t it? Minus the pollution and emissions and environmental hassles. You can easily understand why most energy companies are jumping on the ammonia train today. Firstly, they can use existing oil infrastructure for transporting and producing ammonia.

Secondly, it’s still a billion dollars business and the world’s dependency is even deeper because the food industry will still account for half of the ammonia demand. Thirdly, that’s a nice payback to batteries invasion – because a hydrogen-based economy is very similar to a fossil fuels-based one and requires a lot fewer changes than a battery-based economy.

Ammonia sounds good and all, but…

There’s always that annoying “but”. And it comes down mainly to how sustainable is the ammonia produced. In the Haber-Bosch process hydrogen reacts with atmospheric nitrogen to give birth to ammonia. But guess what – it’s an energy-intensive process AND it’s based on gray hydrogen (sourced from methane).

This kind of ammonia is referred to as gray or brown ammonia. Direct and indirect emissions amount to more than 600 metric tons of CO2 per year. Producing conventional ammonia is nearly twice emissions-intensive than steel production and four times that of cement.

There’s also blue ammonia, which is gray/brown ammonia where the CO2 from methane cracking is captured and stored or is used for enhanced oil recovery. Sourcing ammonia in these ways is not at all sustainable, it contributes to reducing greenhouse gases to merely 10% by 2050.

Green ammonia needs green hydrogen, so it’s the same problem of very expensive processes that need to be overcome. Industry experts are confident they will, while government funds help speed up things. But this will still take many years and by that time same industry experts expect batteries to be much better.

Mass flows in the ammonia supply chain
Photo: International Energy Agency
The International Energy Agency is warning that ammonia production requires new infrastructure, innovation, and investment for near-zero-emission technologies to account for 95% of total production by 2050. This means today’s Big Oil infrastructure is going to need much more than an upgrade.

IEA estimated that by 2050 industry must invest $15 billion per year in new infrastructure. This means by the half of this century we need more than 110 GW of electrolyzer capacity and 90 Mt of CO2 transport and storage infrastructure.

But nearly 60% of those technologies are currently in the demonstration phase. Moreover, ammonia production will require a large part of the energy from renewable projects, and this raises questions about the negative impact on overall electricity costs. So there are big concerns about the future feasibility of an ammonia-based economy.

Ammonia may save the internal combustion engine!

Ammonia is a strong fuel candidate for engines, gas turbines, power generators, and burners. In fact, shipping is expected to be the main client for ammonia, as it could drastically slash emissions in this sector. But could ammonia be used in smaller engines, like those in today’s cars and trucks?

There are some challenges to overcome. Ammonia has an approximately 200°C higher autoignition temperature than gasoline and diesel and also a low flame velocity. It causes low combustion temperature and power reduction in the engine.

That’s why it is necessary to mix ammonia with traditional fuels, either by air intake in its gas form or injecting it into the cylinder as a liquid. It’s very similar to using AdBlue in modern diesel engines – after all, AdBlue is made from urea which is made from ammonia.

Ammonia is still challenging for engines
Photo: Wärtsilä
The bad news is converting a conventional small-sized petrol or diesel engine to work with ammonia fuel is very complicated. Each ammonia-fuel blend would require a different ammonia-fuel blender, injectors, and other engine parts.

Better performances require a higher compression rate in the cylinders and also preheating for ammonia. Because of higher NOx emissions, there are necessary expensive ammonia oxidation catalysts and catalytic reduction.

All of these add a lot to the costs of an internal combustion engine and frankly, it’s not economically feasible for usual cars and trucks. There’s no substantial gain in emissions reduction related to the high costs of the engine and producing of ammonia. In the long term, such a car would become more costly than an EV or a fuel-cell car.

Instead, it is of great importance for big diesel engines in long-haul shipping and trucking. These are low-rpm engines, where injection and burn processes can be better controlled. But the main driver is the tremendous slash in emissions and pollutants, which is the “Achilles heel” for shipping.

Is it really an alternative?

There’s no doubt hydrogen is of great importance for a sustainable future. It will largely contribute to the decarbonization of the energy sector, the main source of GHG emissions in the world. It will also grab a slice of the transportation sector, as it’s more suitable than batteries for heavy applications, like trains, shipping, or airplanes.

Ammonia really seems like a strong contender for sustainably sourcing hydrogen and it also is more interesting as a safer solution than hydrogen to “pack” and “transport” energy anywhere in the world.

Transport of green energy using ammonia
Photo: ARENA
For instance, today’s haulers transporting oil from the Middle East or coal from Australia will someday transport ammonia “packing” renewable energy from solar farms that will be used in special power plants in Japan or South America. Or will be converted into green hydrogen for fuel-cell cars and planes all over the world.

This is truly a vision of sustainability, but there’s a fine line between this and a futile dream. In the meantime, we will continue our heavy fossil fuel dependency and climate problems will worsen. The longer this transition to a hydrogen-based economy, the better for the fossil fuels industry’s “business as usual”.

Keep this detail in mind when you read more and more headlines about how ammonia is the new kid on the block for the sustainable hydrogen future.
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Editor's note: Image of electrolysis by macrovector on Freepik

About the author: Oraan Marc
Oraan Marc profile photo

After graduating college with an automotive degree, Oraan went for a journalism career. 15 years went by and another switch turned him from a petrolhead into an electrohead, so watch his profile for insight into green tech, EVs of all kinds and alternative propulsion systems.
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