Short Summary
Australia’s green hydrogen industry has enormous potential, but many projects are delayed long before production begins. The biggest obstacles aren’t always funding or technology—they’re engineering decisions made during design, instrumentation, safety planning, and commissioning.
This guide explains the key engineering challenges that make hydrogen plants fundamentally different from conventional oil, gas, and LNG facilities. You’ll learn why hydrogen requires different materials, specialised instrumentation, stronger safety systems, and more rigorous commissioning, along with the common mistakes that lead to costly delays and how experienced engineering teams reduce these risks.
Australia has some of the best conditions in the world for green hydrogen. Sun and wind power are cheap. Ports are deep. They sit close to Asian markets. Billions of dollars have followed.
But the numbers tell a harder story. About 50 hydrogen projects were dropped worldwide in 2025, says ING THINK. Few announced projects have reached a final go-ahead on time. That’s based on the IEA’s Global Hydrogen Review 2025.
The gap between a plan and a working plant is engineering. Hydrogen does not act like natural gas or LNG. It leaks through joints that hold other gases just fine. It weakens some metals over time. It often pairs with electrolysers whose output rises and falls with the sun and wind. These are real hydrogen plant risks. Many teams moving over from oil and gas are still learning to manage them.
From our experience, the projects that stall are rarely the ones with bad chemistry or bad costs. They are the ones where a gas-plant design got copied as-is. No one stopped to ask if hydrogen truly acts the same way.
Is This Guide for You?
This guide is for you if you’re:
- Planning or developing a green hydrogen production facility.
- An EPC contractor, Owner’s Engineer or project manager delivering hydrogen infrastructure.
- A process, instrumentation, control or commissioning engineer transitioning from oil & gas or LNG into hydrogen projects.
- Looking to understand the engineering risks that commonly delay hydrogen developments.
- Seeking practical insights into hydrogen instrumentation, functional safety, material compatibility and commissioning best practices before construction begins.
If you’re involved in the technical delivery of a hydrogen project—not just the business case—this guide will help you understand where engineering decisions have the greatest impact on project safety, reliability and long-term performance.
If you’re involved in the technical delivery of a hydrogen project—not just the business case—this guide will help you understand where engineering decisions have the greatest impact on project safety, reliability, and long-term performance.
This piece looks at where hydrogen projects run into trouble. It covers process gaps, instrumentation and control, material choice, safety systems, and start-up on a first-of-a-kind site. Together, these are the base skills for sound green hydrogen work. It builds on our earlier piece on the experience gap in hydrogen. This piece digs deeper into the detail behind that view.
Key point: Hydrogen’s physical traits are a big reason projects stall, not just cost. Leak risk, weak metals, shifting electrolyser loads and long start-up times all add engineering time. Skills from normal gas plants do not fully prepare a team for this.
Why Hydrogen Projects Are Different from Conventional Process Plants
Hydrogen is a smaller, more active molecule than natural gas. That’s the main reason hydrogen plants differ from normal gas plants. Hydrogen molecules are the smallest of any gas. This gives hydrogen a much higher leak risk than methane, even through joints that seal natural gas just fine. Hydrogen can also weaken some steels over time. And it is often paired with green power, which makes electrolyser output shift instead of stay steady.
Natural gas and LNG plants run on decades of set design rules. Their feed is fairly steady. A hydrogen plant adds new risks all at once:
- Leaks. Hydrogen molecules are small enough to pass through seals and joints that hold natural gas just fine. Joints, valve packing and flange links need tighter checks and more leak tests.
- Hydrogen embrittlement. Under steady pressure, hydrogen can enter some carbon and low-grade steels. Over time, this makes the metal weaker. Material choice must plan for long-term exposure, not just the first pressure rating.
- Power swings. A gas plant runs on a steady fuel feed. An electrolyser plant often runs on sun or wind power instead. Output can swing a lot within one day. The control system has to manage that swing without a trip.
- High-pressure storage. Hydrogen is often stored between 350 and 700 bar. It can also turn to liquid at around minus 253°C. Both paths bring their own tank design and boil-off needs.
- Electrolyser fit. Electrolysers add a layer of chemical process control. Most gas engineers have not worked with this before. Electrolyser plant work is its own field. It needs to be treated as one.
Skills from LNG, oil and gas work do help here. Safety layers, safety systems and strict change control all carry over. But skill alone is not enough. Teams need to know where hydrogen changes the design base. Gas-plant thinking cannot just be copied onto a new fuel.
Real-world case: Picture a hydrogen export site. Green power output suddenly drops by 40%, say a cloud rolls in over the solar farm. The electrolyser control system must cut output. At the same time, it must hold stack heat, gas purity and pressure inside tight limits. Without good control logic, the plant may trip for no good reason. That trip can delay output by hours or days while staff work through a restart.
Hydrogen vs Conventional Process Plants
| Factor | Natural Gas / LNG Plant | Hydrogen Plant |
|---|---|---|
| Molecule size | Larger, lower leak risk | Very small, higher leak risk |
| Material risk | Corrosion, erosion | Embrittlement of certain steels |
| Feed stability | Generally steady | Often variable with renewable power |
| Storage pressure | Typically lower | 350–700 bar, or cryogenic |
| Design code maturity | Decades of established codes | Standards still evolving |
Electrolyser — a piece of gear that splits water into hydrogen and oxygen with an electric current. Green hydrogen plants use electrolysers run by green power. That’s why electrolyser output tracks the sun and wind rather than staying flat.
Two electrolyser types are in wide use on hydrogen sites today.
- PEM electrolyser (Proton Exchange Membrane) — uses a solid film. It reacts fast to shifts in power input and suits shifting green power well.
- Alkaline electrolyser — an older, well-proven type. It operates using a liquid mixture and generally offers a lower cost per unit of production. It reacts more slowly to load swings than PEM.
PEM electrolyser in more depth: the film is thin and the reaction is fast. So PEM units can ramp up and down within seconds. This makes them a top pick where power supply shifts a lot. A plant run straight off sun or wind, rather than firmed grid power, often picks PEM for this reason.
Alkaline electrolyser in more depth: this tech has decades of use in fields outside hydrogen energy. It often needs a steadier load to run well. So alkaline plants are often paired with power firming or battery backup when the main supply is green power.
Hydrogen embrittlement occurs when hydrogen atoms enter a metal and weaken it. The metal loses strength and flex over time. Carbon steel and low-grade steel are more likely to experience problems when exposed to continuous operating pressure. It is a slow build-up, not a sudden break. That is exactly why it gets missed. If a team picks steel based on pressure rating alone, this risk can slip through.
Instrumentation and Control Challenges Specific to Hydrogen
Hydrogen plants need special sensors and gear. Hydrogen leaks more than natural gas. It burns with a flame you can barely see. And it works under fast-changing conditions. Leaks are harder to catch than in a gas plant. Electrolyser loads shift all the time. A missed leak has worse results.
Electrolyser control. An electrolyser must follow a power input that shifts. At the same time, it must keep stack heat, pressure and gas purity in tight limits. This needs control logic that can ramp up and down with ease. Getting this loop wrong is a top cause of trips in new hydrogen plants.
From our experience, most start-up delays trace back to this one control loop. Single items of gear pass their own tests without issue, most of the time. The problems show up later. That’s when the electrolyser, the rest of the plant, and the safety system must all react to the same load swing at once.
Hydrogen sensing. Hydrogen burns with a flame you can barely see. It also has a wide burn range, roughly 4% to 75% in air. Natural gas, by contrast, sits around 5% to 15%. So gas sensors need to run all the time, not just now and then. Sensors sit at pump seals, flange links, tank areas, and any closed space where hydrogen could build up.
Pressure checks. Pumps, tanks and pipes all need gear that tracks pressure trends close up. This catches a growing fault before it turns into a crisis. Backup pressure sensors should feed into the safety system, not just the main control loop.
Safety Instrumented System (SIS) — an auto system, set by IEC 61511, that shuts gear down safely. It acts when unsafe signs show up. In a hydrogen plant, the SIS watches pressure, heat, flow and gas sensor signals. If any of these move past a safe range, it triggers a shutdown.
Emergency Shutdown (ESD) valve — a fail-safe valve that seals off a risky part of the plant. It shuts when the SIS calls for a shutdown. In a normal sequence, sensors spot a fault. The SIS logic checks the signal. The ESD valve then drives shut, often within a few seconds. Fast-acting drives and IECEx-rated panels are the norm here. A slow-shutting valve weakens the whole safety plan.
Sarom Global’s Instrumentation & Control team works this full loop. That spans electrolyser control setup through to SIS and ESD valve choice. The goal is simple: a safety system and a control system built to work as one, not bolted on apart.
Key point: Hydrogen safety gear must plan for shifting loads, fast leaks, and tight shutdown timing. Control logic copied from a normal gas plant will often miss one of these.
Safety and Material Compatibility Considerations
Hydrogen brings risks that normal gas plants rarely face. The gas acts in a different way with metals, seals and rated gear.
Steel and metal choice. Some carbon steels and strong alloys face more risk of hydrogen embrittlement. This risk grows under a load that cycles. Picking the wrong steel grade, or the wrong seal type, can cause early failure. This often shows up as a leak long before it shows up as a clear fault.
From our experience, embrittlement risk gets caught in design checks far more than in buying checks. A spec sheet can name the right steel grade on paper. But a supplier can swap in a look-alike alloy without a flag. That gap can then sit hidden for years once the plant runs.
Seal and valve fit. Valve trim, seats and seals must be rated for hydrogen use, not just for pressure and heat. This is one reason trunnion-mount ball valves are common for high-pressure hydrogen lines and tanks. Their seal design suits fast, tight shut-off work.
Rated area gear. Tools, drives and panels near hydrogen zones need IECEx or equal rating. This is not a choice. Hydrogen has a wide burn range. Its spark point is low too, roughly one-tenth that of natural gas. So gear that is safe in a gas plant is not safe by default in a hydrogen plant.
IECEx is a rating scheme for gear used near blast risk. In short, it proves that a tool, drive or panel is safe to place in a risky zone. Risky zones are spots where gas can build up. Hydrogen’s low spark point makes IECEx rating a must-have. Gear rated for other gases may not suit hydrogen use.
Safety Integrity Level (SIL) — a score for how well a safety task works when called on. ESD valves and their SIS loops are set and test-checked against a fixed SIL target. That target must be checked again through the life of the plant. It is not a one-time check at design stage.
Rules are still taking shape in this space. Australia does not yet have one set hydrogen safety code. Queensland leads the way with its Hydrogen Safety Code of Practice. It brings fuel gas rules for hydrogen into one place. This swaps out old rules built for LPG and natural gas. Other states sit at earlier stages. Project teams often work across a mix of codes instead. These include AS/NZS standards, IEC 61511 safety rules, and IECEx rating. Where local codes lag, teams lean on global guides.
IEC 61511 is the global rule set for Safety Instrumented Systems, or SIS. It covers risky plant fields such as oil and gas, chemical work, and now hydrogen too. The rule set lays out life-cycle steps for an SIS, from the first risk check through to shut-down. It covers how to set, build, run and fix the system at each stage. Learn more from the IEC direct.
AS/NZS standards are joint Australian and New Zealand rules. Standards Australia and Standards New Zealand work together to develop and keep these standards up to date. For hydrogen sites, the key AS/NZS rules cover tank design, rated gear and risky zone class. They fill the gaps while hydrogen-only codes are still being drafted.
ESD valves sit at the core of this risk picture. A well-set ESD valve is one of the clearest ways to prove risk cuts. It must be kept in check and test-checked. This matters to regulators, insurers, and lenders alike.
Common Engineering Mistakes in Hydrogen Plants
- Using hydrogen like natural gas. Reusing a gas-plant design without a fix for hydrogen’s small size and wide burn range.
- Copying LNG sensor specs. Sensor spots and check times built for methane leaks, not hydrogen.
- Weak leak coverage. Gaps at pump seals, flange links, or closed spots where hydrogen can build up unseen.
- Guessing short on start-up time. Setting a hydrogen start-up phase as if it were a normal gas plant.
- Skipping weak-metal risk in steel choice. Picking steel grades by pressure rating alone, with no plan for long-term hydrogen exposure.
Commissioning a First-of-a-Kind Hydrogen Facility
Start-up takes longer on hydrogen sites. Each linked system must be checked under set conditions before gas flows. This can take up 10–20% of a full project schedule, based on plant size. Each system, from electrolyser to tank to shutdown gear, must prove itself twice. First on its own. Then with the rest.
Factory Acceptance Testing (FAT) runs before gear leaves the maker’s site. It checks that sensors, control logic and safety tasks work as built, in a set space. This catches setup faults before they reach site.
Site Acceptance Testing (SAT) repeats and adds to that check once gear is placed. It checks that all parts work right in their real space, and link well with the rest of the plant.
Between FAT and SAT, hydrogen start-up often means:
- Loop checks — proving each sensor signal reaches the right control or safety input.
- Function checks — proving control logic, locks and ESD steps act just as planned.
- Load checks — testing the electrolyser and control plan against real load swings before gas flows.
- Full checks — running the plant as one linked system, not as loose parts, to catch link faults.
- Staff training — building staff know-how on hydrogen risks and crisis steps before live gas flows.
From our experience, most delays occur during full checks, not gear set-up. Link faults only show up once many parts run as one. A control valve can work well on its own. But it can act in a new way once it talks to a live safety system. Add a shifting electrolyser load at the same time, and small clashes turn into real delays.
FAT vs SAT
| FAT | SAT | |
|---|---|---|
| Location | Manufacturer’s facility | Installed site |
| Purpose | Confirm design and configuration | Confirm real-world integration |
| Timing | Before shipment | After installation |
| Typical focus | Instrument calibration, logic testing | Loop checks, interlock testing, live commissioning |
On a first-of-a-kind site, none of these steps can be taken as a given. The last plant a team built was likely a normal one. Sarom Global’s work across FAT, SAT and plant fine-tuning is built to catch link faults early, before they turn into run-time faults.
Key point: Start-up times on hydrogen sites run long by plan, not by waste. Skipping steps to save time on a first-of-a-kind site tends to push the cost into the run phase instead.
Closing the Experience Gap
Hydrogen sites mix chemical work, power systems, automation and safety design. Few single engineers have worked all of these hydrogen risks at once before. That’s the core of the skills gap we cover in our earlier piece. It’s why cross-skill support matters at each stage of a project.
A modern hydrogen plant is not just a normal plant with a new fuel. It mixes chemical work, green power tie-in, automation, high-pressure tanks and safety design into one tight web. That tight web is why hand-offs between teams cause so much trouble.
Owner’s Engineering support gives a project owner a clear, outside view across the full job. It does not lean on just one build firm’s own view. Outside checks at key points catch design gaps early, while they are still cheap to fix.
From our experience, the projects that dodge rework share one trait. Sensor, start-up and safety teams check the control plan as a group, before it is locked in, not after. A control plan locked in with no start-up team input tends to turn up as rework later. So does a safety plan built with no input from the sensor team who will run it day to day.
Cross-skill work cuts delays, cost blowouts and run risk. It catches the clash points between systems that a single-skill check will miss. For a firm on its first hydrogen site, this kind of check matters. It’s often the gap between a plant that runs well and one that stalls in start-up.
Sarom Global works across Owner’s Engineering, process engineering, sensor and control work, and start-up support for power and process sites, hydrogen included. Get in touch to talk through your project’s risks.
Frequently Asked Questions
Conclusion
Hydrogen’s future in Australia turns on more than cheap green power. It turns on sound design, strong process control, tough safety systems and firm start-up work. Some projects treat these as a side note to the cost case. Those are the ones most set to show up on next year’s drop list.
Firms that back skilled, cross-field teams sit in a better spot to win. Their hydrogen sites tend to run safer, run better, and win more trust from lenders. If your site works through sensor, safety, or start-up risks, check out Sarom Global’s work. Or get in touch to talk through where your project stands.