Part 2: Understanding where and why it beats today’s options and other low-carbon solution.
In the first instalment of the series we looked at the key factors driving the competitiveness of hydrogen as a solution. Namely: Asset utilisation; Volume of Energy; and Mobility / ‘off-grid’ consumption of energy.
In this post we will be looking at application which exist today where hydrogen is better than incumbent solutions. As before, we will be referring to they Hydrogen Council’s report “Path to Hydrogen Competitiveness” and their excellent chart “Exhibit 5” (see below for a copy of the chart).
Hydrogen, the star performer steals diesel’s show
For many applications hydrogen can outperform conventional options in terms of green credentials, cost and performance. While Exhibit 5 is the Hydrogen Council’s view for 2030, for some applications hydrogen is also the most competitive option today. Examples of current competitiveness include forklifts and certain instances of large off-grid or temporary use generators (although temporary use generators are not covered in the report). In short, for applications in the top right quadrant of the chart (being both the most competitive low-carbon solution, and more competitive than conventional options) we do not need to make sacrifices to go green, and hydrogen is the way to do it, even today.
Looking back at the factors established in the last blog post we see that all of the applications in the top right quadrant of the chart have a few things in common. They are either transport or mobile applications (and therefore off-grid). They all require large volumes of energy as they are either pulling heavy loads, going long distances or doing both. Many do not get much down time as they want to be continually operating to achieve a return on a high capital asset; they are highly utilised. And all of the applications are currently served by diesel.
Let’s consider a couple of examples: Heavy duty trucking and SUVs.
Heavy duty trucking
I won’t dwell on this one long as it is well covered elsewhere2, but this is one of the clearest cases for switching to hydrogen. It is a use case which ticks all three of the drivers:
- A large amount of energy is needed both from pulling a large mass and from travelling large distances.
- It is an asset where you do not want it taking breaks. In many cases these days a truck will have two drivers and as we move to autonomous trucking breaks will no longer be required for humanitarian reasons.
- It is inherently ‘off-grid’ due to its mobility.
It is a use-case that will win out over batteries. This if for two primary reasons: the large energy requirement forces the need for a very large heavy battery, which in turn means a heavier system as larger heavier motors are needed etc. Whereas for hydrogen, once the required size of fuel cell is installed, range is increased for relatively little weight by adding more hydrogen and as you go the distance and consume the hydrogen, the truck gets lighter and the economies get better. The need for high asset utilisation sits at odds with a battery need to be recharged (note: fast charging is the opposite of what a battery chemistry wants and it degrades the battery faster) where as a hydrogen tank can refill 15x faster. Additionally, because of the increased energy density of a hydrogen system it can go farther for the same truck footprint, increasing the time spent on the road.
Sports Utility Vehicles are an example of a case that is a good case for hydrogen but less of an all-out winner. This is because we have two of the three driving factors being high and the third slightly lower. The volume of energy is high due to the size of the vehicle and their intended use for pulling larger weights, carrying more passengers, or travelling larger distances on and off road. The mobility/off-grid driver is also clearly high, both due to it being a vehicle, but also one that is often used to travel larger distances so spends longer periods of time away from a charge point.
More opportunities to consider
There are more opportunities beyond only those covered in the Hydrogen Council’s report. Applications such as those relating to non-road mobile machinery (NRMM, e.g. mobile temporary-use diesel generators, or heavy machinery such as tractors or road construction equipment) are particularly suited to hydrogen and account for a significant proportion of diesel consumption in the UK and globally. Hence, they are important to consider as part of the bigger picture. These applications are ones that are currently heavily served by diesel and because of their dual requirements of portability and large energy consumption it means that we need a storage mechanism with a high energy density. For the majority of these applications the energy density of batteries are not great enough to meet the energy demand within a reasonable weight and size footprint, and their recharge time doesn’t fit with operational requirements.
We have overlaid these applications onto the chart produced by the Hydrogen Council. As part of this we have broken temporary use generators down into small, medium, and large, with ‘small’ being hand portable (c. 4kW or smaller), medium being trailer sized generators (c. 10kW – 60kW), and large being skid mounted, large trailer or shipping container sized generators (c. 60kW+).
But is hydrogen really green?
One of the primary reasons for interest in using hydrogen as an energy storage medium is it having a low to zero-carbon footprint. Now, you will often hear the argument against hydrogen being that the majority of hydrogen currently produced releases large amounts of CO2, and this is true. Currently most hydrogen is made from methane through a process called Steam Methane Reforming. This produces what is often called “Grey Hydrogen” or “SMR Hydrogen”. However, when we compare against diesel in looking at the amount of CO2e per kWh of energy delivered to the end application, in many cases Grey Hydrogen still only produces a fraction of the CO2e. This is because of the real-life operating inefficiencies of diesel engines. This is particularly true when looking at the real-world use and efficiencies of diesel generators. Even when using Grey Hydrogen we still only produce 1/3rd the CO2e compared to using diesel.
We can of course reach zero-carbon in our energy production / use by using “Green Hydrogen”. This is hydrogen produced by using renewably produced electricity (typically from solar or wind) to break down water through electrolysis.
Electrolysis, very simply put, is when an electric current is passed through water to break down the water into hydrogen and oxygen. We then capture and bottle the hydrogen, thus storing the energy for later release by putting it through the reverse process.
Currently this costs more than making Grey Hydrogen and thus Green Hydrogen is more expensive as a fuel. However, from our modelling Green Hydrogen can still be cost competitive against real-world costs of diesel. This is for a range of factors, but a key one is due to the technical constraints of a diesel generator and resulting operating inefficiencies.
“It costs too much!” I hear you say
Last but not least hydrogen can out compete diesel on cost. Often diesel engines operate very inefficiently and have high maintenance requirements, which leads to a higher total cost of use than if we look at the cost of diesel alone. This inefficiency in operation brings the total cost of use of hydrogen solutions in line with diesel powered systems in circumstances of high generator utilisation. I.e. the cost per kWh of delivered electricity is comparable between hydrogen and diesel.
This theoretical look is reinforced by real world examples. While hydrogen systems might not yet be prevalent there are examples where hydrogen solutions are being deployed. Hydrogen is already commonplace in warehouses, powering forklift trucks and for backup power for telecommunications towers. Several automotive giants3 such as Hyundai, Toyota, Volvo and Daimler (in a $1.3bn JV), and up and coming Nikolai, are starting to roll out hydrogen heavy duty trucks and even a few SUVs. Finally, while not common, hydrogen has been used to power ferries, schools (through combined heat and power units) and even starting to power trains.
We can see that the combination of the three driving levers with additional benefits for different use-cases, means that hydrogen isn’t just a future answer; it is an answer now. Which begs the question why we aren’t seeing faster shifts in adopting hydrogen for these applications where it out competes conventional and other low-carbon technologies. That question is best left for another discussion.
In the next and third instalment of this series we will be looking at the transition cases. Those where hydrogen’s viability must be evaluated on a case-by-case basis (the intersections between quadrants) and looking at examples of some of the considerations that need to be made.
If you have questions on anything above, or want to find out more about how you could utilise hydrogen then get in touch.
- Hydrogen Council “Path to Hydrogen Competitiveness”;https://hydrogencouncil.com/wp-content/uploads/2020/01/Path-to-Hydrogen-Competitiveness_Full-Study-1.pdf
- For an unbiased and relatively comprehensive look at fuel cell heavy duty trucks the article “A closer look at hydrogen fuelled trucks” in Commercial Motor is worth a read; https://www.commercialmotor.com/news/buying-advice/closer-look-hydrogen-fuelled-trucks
- A brief article covering some of the automotive moves in hydrogen fuel cell HGV trucking. Forbes “Daimler, Volvo Trucks Team Up On Hydrogen Fuel Cells For Heavy Trucks”; https://www.forbes.com/sites/greggardner/2020/04/21/daimler-volvo-trucks-to-team-up-on-heavy-truck-fuel-cells/