Photo credit: Nuclear Reimagined, Third Way Think Tank/Gensler
Many see hydrogen as the golden key to our completely decarbonized and clean energy future. There are many compelling reasons that the golden key to unlock the door to a clean ethical and prosperous energy future is likely in the shape of “nuclear hydrogen.” According to a recent study by Energy Options Network (EON), nuclear innovation provides the most scalable and economical route to produce hydrogen at large industrial scale without producing harmful emissions and importantly that is cost-competitive.
Hydrogen has many industrial uses today and many more potentially in the future. Today it is used to upgrade crude oils, to make the materials in the products we use everyday, to make ammonia-based fertilizers. Ammonia is essential to our ability to grow the foods we need, so our lives depend on ammonia and by extension industrial hydrogen production.
In the future, hydrogen could replace coke for refining clean steels and other metals and bring steel production back to western markets that have responsible environmental standards. Hydrogen can be used to upgrade natural gas for residential heating in the same way that ethanol is used to upgrade gasoline. It can be used directly as a transport fuel or indirectly in the production of synthetic gasolines, diesels and kerosenes – all required for planes, trains, trucks, buses, ships and cars. It is obvious then that hydrogen is critical component of a clean, green and ethical industrial economy.
How do we produce that hydrogen?
Hydrogen production requires a lot of energy – a lot. The amount of energy we need for 1 Kg of hydrogen depends on how we produce it and the feedstock. As we look at each, remember that energy is money, so energy efficiency in hydrogen production is the same as cost efficiency. We can only create a hydrogen economy if hydrogen production is cost efficient, and that means energy efficient too.
Let’s first look at the feedstock for hydrogen production.
There are two plentiful sources of hydrogen in the world today: water (H2O); and, methane (CH4). Here is the first key obversation: It takes five to six times the amount of energy to remove hydrogen from water than from methane. Clearly if we can, we want to use methane as our source of hydrogen and not water… and we can!
There a number of methods, two are relevant – Steam Methane Reforming (StMR) and Pyrolysis (PyS). StMR is the dominant industrial method today, and PyS, of which there are numerous technologies is being demonstrated at commercial level today.
The industrial world is getting interested in PyS as it has a tremendous advantage when it comes to CO2. The chemical byproduct of StMR is gaseous CO2, but with PyS there is none, only stable and valuable solid carbon. PyS solves the CO2 problem from using natural gas as a hydrogen feedstock, at least with respect to the chemical byproducts of hydrogen production.
Returning to H2O as a feedstock, and ignoring its 5x energy problem for a moment, hydrogen production from water is done by electrolysis. As this depends on electricity generation and transmission this adds another layer of complexity – pure electrolysis requires many times the electric energy compared to PyS of methane. Electrolysis of water thus has a big feasibly problem for industrial-scale hydrogen supply.
Electrolysis may only work economically in the context of stranded electric power, a reflection of inefficiencies in the market structure and policy design of electric power markets – stranded energy is without value – Calfornia and duck curves come to mind. Stranded energy may also occur at some nuclear power plants today which are forced to idle for an hour or two a day due to excess wind and solar generation.
So what about the vast amounts of electrical and thermal energy to drive the PyS progress at the industrial scaled for our hydrogen economy? We cannot use fossil fuels, because we want clean zero-CO2 hydrogen.
Enter Generation IV reactor technology and Terrestrial Energy’s IMSR. The IMSR, as with many other Generation IV reactor technologies, operates at the high temperatures needed for PyS. The IMSR can supply thermal and electric energy to drive PyS hydrogen production, and do so at a cost equivalent to fossil fuels, but with no CO2 emissions!
So the hydrogen production formula getting smart attention is the combination of natural gas feedstock, zero-CO2 PyS, and a Generation IV nuclear plant for the clean energy to drive the whole process. This is what the hydrogen golden key may look like. It has all the essential attributes – capital and cost efficiency, zero CO2 and scalability.
Addressing Scalable Hydrogen Production
We should touch finally on this point of scale. The hydrogen economy will require an extraordinarily large amount of energy. If we are to achieve scale, the scale factor must be front and center in our assessment of choices. Based on some basic and simple analysis, the limited role of alternative methods becomes clear. Today 83 percent of our primary energy demand still comes from fossil fuels. Nuclear energy has already proven its ability to scale fast, and Generation IV nuclear energy too can scale fast.
Source: Energy Options Network
A September 2020 Lucid Catalyst report came to a similar conclusion, finding that using advanced nuclear with its high-temperature heat could be the key to unlocking scalable, cost-competitive hydrogen.
“The potential of advanced heat sources to power the production of large-scale, very low-cost hydrogen and hydrogen-based fuels could transform global prospects for near-term decarbonisation and prosperity,” the report noted.
If nuclear hydrogen replaces just a fraction of oil and gas demand with nuclear-generated hydrogen, the EON report projected we would need 4,000-6,000 gigawatts of additional nuclear capacity by 2050.
Sources: BP Annual Energy Outlook, IAEA, World Nuclear Association, Energy Options Network
That is a lot of nuclear energy production. Run the numbers yourself on alternative energy choices and the conclusion will be clear. The hydrogen economy that excites so many requires massive amounts of energy. The case is compelling that nuclear hydrogen with natural gas (methane) pyrolysis is the golden key to a clean, green future.