Molecules
Hydrogen H₂
The lightest molecule, the highest energy per kilogram, and the hardest to store and move. Everything difficult about hydrogen follows from those three facts.
The entry point
What it is
Hydrogen is the simplest and lightest element, and carries more energy per unit mass than any other chemical fuel — roughly 120 MJ/kg on a lower-heating-value basis, about 2.5 times that of natural gas. It also has extremely low energy density per unit volume, which is why almost every practical hydrogen problem is a storage and transport problem rather than a production problem.
How it is produced
Water electrolysis
Splitting water with electricity. Alkaline and PEM are commercially mature; AEM and solid-oxide are earlier but promise higher efficiency. Cost is dominated by electricity price and load factor, not by the stack.
Steam methane reforming
The incumbent route and the source of most hydrogen produced today. Cheap where gas is cheap, and carbon-intensive unless the CO2 is captured.
Reforming with carbon capture
Reforming plus CO2 capture and storage. Lower emissions than unabated reforming, with the achieved carbon intensity depending heavily on capture rate and upstream methane leakage.
Other routes
Pyrolysis producing solid carbon, biomass gasification, and naturally occurring geologic hydrogen — all at earlier stages of commercial deployment.
Conversion
Hydrogen is frequently converted into a carrier before it is moved: into ammonia, into methanol, into synthetic methane, or into liquid organic carriers. Each conversion costs energy and each reconversion costs more, so a carrier is only worth it when the transport problem it solves is larger than the losses it introduces.
Storage
Compressed gas (typically 350–700 bar for mobility, lower for stationary), cryogenic liquid at around −253 °C, or chemical storage in a carrier. Salt caverns are the credible option for large-scale, long-duration storage. Hydrogen also embrittles many steels and leaks through seals that hold natural gas, which constrains material and component selection throughout.
Transport
Pipelines are the cheapest option at volume over land, either purpose-built or repurposed from natural gas subject to material compatibility and blend limits. Over long distances and across water, shipping as ammonia or methanol is usually cheaper per delivered unit of energy than shipping liquid hydrogen, because liquefaction is energy-intensive and boil-off is persistent.
Infrastructure
Production plant, compression, storage, pipelines or trucking, and end-use connections — plus the safety, metering and certification layers around them. Infrastructure is the most common binding constraint on hydrogen projects and the most commonly underestimated line in early cost models.
Economics
Delivered cost is dominated by electricity price and load factor for electrolytic hydrogen, and by gas price and capture cost for reformed hydrogen. Capital cost and cost of capital matter substantially at low load factors. The commercially important number is almost never the production cost at the plant gate — it is the delivered, certified cost at the customer's boundary, which can be considerably higher.
Applications
- Refining — hydrotreating and hydrocracking, already a large existing hydrogen consumer
- Ammonia synthesis for fertiliser and as an energy carrier
- Methanol synthesis for chemicals and fuel
- Steel — direct reduction of iron ore as an alternative to coke
- High-temperature industrial heat where electrification is impractical
- Heavy transport, shipping and aviation via derivatives
- Long-duration energy storage and dispatchable power
Commercial challenges
- Delivered cost remains above the price most buyers currently pay for the grey equivalent
- Storage and transport economics penalise small volumes and long distances
- Certification regimes differ between markets, so a project can be eligible in one and not another
- Offtake is scarce relative to announced production capacity
- Infrastructure is frequently missing and rarely funded by the production project
Questions
Why is hydrogen hard to store and transport?
Because it has the lowest volumetric energy density of any fuel. Storing usable quantities requires very high pressure, cryogenic temperatures around −253 °C, or conversion into a carrier molecule — and each of those adds cost and energy loss. It also embrittles many steels and leaks through seals that contain natural gas.
Is green hydrogen the same as renewable hydrogen?
In common usage yes, but colour terms are being replaced by measured carbon intensity in certification schemes, because that is what actually determines market eligibility. A project can be described as green and still miss a scheme threshold depending on how its electricity is accounted for.
Where does hydrogen make most commercial sense today?
Where hydrogen is already consumed and can be substituted without new end-use infrastructure — refining and ammonia production above all. Those buyers have an existing mandate, an existing procurement route and a known volume, which is why they are the most tractable early market.
Where hydrogen matters
How we can help
Techno-Economic Analysis
Levelised cost modelling with the assumptions exposed and the sensitivities tested.
Read more →Technology Assessment
Independent, criteria-driven comparison of the technologies competing for your project.
Read more →Offtake & Buyer Discovery
Finding and qualifying the buyers a production project needs to be financeable.
Read more →Working with hydrogen?
Whether you produce it, buy it, build for it or are deciding whether it fits your region, the starting point is the same conversation.