
Is Blue Hydrogen Really Green
- Posted by Callum Russell
- Date December 21, 2021
What is Blue Hydrogen?
Hydrogen is the first element found on the periodic table. This is the most basic and fundamental element in the universe. The immense energy potential of hydrogen makes it a very lucrative but also incredibly dangerous fuel source. Take for instance the sun! This is essentially a massive ball of hydrogen gas that undergoes fusion reactions to form helium. We won’t get too technical in this post, however, feel free to get in touch if you want to learn more about the chemistry and physics behind hydrogen.
Before we go into the details of what exactly is blue hydrogen, we must first consider the different types of hydrogen. When we refer to different types of hydrogen, we are simply referring to how they are made, and the level of emissions required within the process.



1. Grey Hydrogen
Grey hydrogen is the most common form of hydrogen and is generated from natural gas (consisting mainly of methane and ethane). The process is often referred to as Steam Methane Reforming (SMR), and can account for up to 96% of hydrogen production.
This fossil fuel powers most commercial and industrial gas boilers and stoves. Scientists have confirmed that this is a key player in carbon emissions that contribute to global warming. This is what gives this hydrogen its colour identifier, as grey isn’t a bring and welcoming colour.
2. Brown Hydrogen
Brown hydrogen uses lignite coal (also known as brown coal, generated over millions of years by compressed peat deposits) or oil. Black hydrogen is produced using bituminous coal – a tar-like substance. Which makes sense, since coal is black and extremely harmful for the environment.
The process of extracting hydrogen from all of these options emits CO₂ to differing degrees, and so they are not a suitable pathway for reaching net-zero emissions with hydrogen. However, as we discuss in another post, the realisation of net-zero emissions isn’t going to be realised unless we can create negative emissions to counterbalance the carbon output over the last several decades.
3. Green Hydrogen
Green hydrogen is produced by using zero-carbon electricity – such as that generated by wind turbines or solar panels – to split water into hydrogen and oxygen, through a process known as electrolysis. The process is carbon-neutral since the electricity has come from non-fossil fuel sources, however, green hydrogen is very expensive and is expected to remain until at least 2030.
Despite this high cost, the efficiencies of the electrolyzer are increasing, which will hopefully reduce the cost of green hydrogen, however, current markets suggest this won’t reach prices of grey hydrogen for several decades.
4. Blue Hydrogen
But blue hydrogen is a relatively new concept, it’s hoped, particularly by the US and UK governments, to be as sustainable as green hydrogen, with the reduced costs associated with grey hydrogen. Blue hydrogen is produced using the same reforming process that is used to create grey, brown and black hydrogen, but the CO₂ that would ordinarily be released is captured and stored underground. Currently, as of 2021, there are only two blue-hydrogen facilities, one operated by Shell in Alberta, Canada, and the other by Air Products in Texas, USA.
Carbon capture and storage equipment are expensive, raising the price of the fuel, but it at least provides for low-carbon fuel production at a lower cost than green hydrogen. There is however a huge misconception surrounding blue hydrogen, which many believe that this process has “zero emissions” however, this simply isn’t the case, not all of the emitted CO2 is captured and stored.



So Whats The Problem?
There are essentially two ways to make blue hydrogen, and both rely on steam reformation, the process of using high heat, pressure, and steam that cracks methane and water to produce hydrogen and carbon dioxide. For both approaches, carbon dioxide from steam reformation is captured and stored or used. The difference between the two is whether carbon dioxide is captured from the generators that power the steam-reformation and carbon-capture processes.
When you add it all up, capturing carbon from all parts of the process—steam reformation, power supply, and carbon capture—eliminates just 3 percent of greenhouse gas emissions compared with only capturing carbon from steam reformation. The lowest-carbon blue hydrogen had emissions that were just 12 percent lower than for gray hydrogen.
Blue hydrogen’s Achilles’ heel is the methane used to produce it. Methane is the dominant component of natural gas, and while it burns more cleanly than oil or coal, it’s a potent greenhouse gas on its own. Over 20 years, one ton of the stuff warms the atmosphere 86 times more than one ton of carbon dioxide. That means leaks along the supply chain can undo a lot of methane’s climate advantages.



Are The Policies Fit For Purpose
The UK government has said it wants 5 GW of “low-carbon” hydrogen capacity by the end of the decade. Oil and gas giants BP and Equinor, taking a cue from government announcements, both announced plans for massive blue hydrogen plants in the country with outputs of 1 GW and 1.2 GW, respectively.
The new study also casts doubt on some plans to shift transportation to hydrogen. Some sectors, like freight and aviation, may end up requiring hydrogen for certain routes. But cars and trucks, which many countries say must be zero-emitting by 2035 or sooner, will have a harder time justifying a switch to hydrogen over straight electrification. Companies that have bet their future on hydrogen, like Toyota, are in a tight spot as their bridge to a truly zero-carbon portfolio takes a hit.
Not all hydrogen suffers from these problems, of course. Green hydrogen, which is made by splitting water using wind or solar power, doesn’t suffer from the same carbon accounting issues. But neither does it reuse oil and gas companies’ existing infrastructure. So while this new study seems to be a pretty damning indictment of blue hydrogen, it’s unlikely to be the final nail in its coffin.



So What Is The Future?
As cleshay as it is, no one can predict the future, however, we can take an educated and calculated assumption of what the future of energy production might be.
We know for certain that the future of energy will move away from traditional fossil fuel systems, however, by what extent is yet to be relaised. It’s important to remember that this is the first generation to discuss and implement some plant to combatting climate change, and begin the long process of correcting the issues that date back to the industrial revolution. That will take time.
Controversial to public opinion is that I believe the net-zero targets for 2030 are unrealistic and are set up for failure. The technology required isn’t there yet, nor is the economics worthwhile for investors. This suggests in reality it’s a numbers game, regardless of the urgency to reduce emissions!
In a hypothetical world, renewables will provide the globe with 100% of its required energy, without the reliance on coal, oil, or natural gas. The current and near-future won’t see this come to fruition. What we will see is a reduction in the quantity of fossil fuel consumption, with the integration of renewable sources.
It will take time, it will take innovation, and out of the box thinking, but one day I do believe the world will run on pure 100% green energy, but in this lifetime, I don’t think it will reach its targets. That doesn’t mean we shouldn’t strive for the 2050 target, but we must be conscious that it’s a tall order and a Herculean task.
Let us know your thoughts in the comments!
My name is Callum Russell, I am the founder of The ChemEng Student, and a Chemical Engineering & Project Manager Lecture in the UK. My current active research is on the development of high-value biochemical compound extraction using novel, Switchable Hydrophilicity Solvents.
Having over 9-years of teaching experience, I have combined my passion for chemical engineering and teaching to create this truly unique learning community. My main areas of expertise lie in Heat Transfer, Distillation, Pinch Technology, Reactor Design, and Thermodynamics.
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