How hydrogen combustion enhancement works.
No jargon, no protected detail, no percentages. Just where the gas comes from, where it goes, and the established physics of why a small hydrogen fraction changes how the primary fuel burns.
What is actually happening inside the engine?
An electrolyser on the vehicle splits deionised water into hydrogen and oxygen while the engine runs, and that small gas volume is drawn into the intake air. Hydrogen has a much higher flame speed than diesel or petrol and ignites across a far wider mixture range, so its presence in the charge helps the primary fuel burn more completely and earlier in the stroke rather than continuing late. The engine still runs on its normal fuel; nothing is stored, and nothing enters the fuel system.
- Gas is generated on demand only while the engine runs — no storage cylinder
- Entry point: after the air filter, before the turbocharger or throttle body
- Mechanism, established physics only: flame speed and flammability range
- Effect: combustion completeness and burn phasing of the primary fuel
- Not a fuel replacement, not a conversion, fully reversible
- No emissions-compliance, certification or defect-clearance claim
- Feed
- Deionised water
- Power
- 12 / 24 V DC
- Entry
- Intake air, pre-turbo
- Storage
- None — on demand
Where the gas comes from and where it goes.
Where it lands in the cycle.
Air plus the small H₂ / O₂ fraction is drawn in
Charge is compressed; fuel is injected or the mixture is prepared
Ignition and expansion — where burn timing matters most
Products are expelled; unburnt fuel here is wasted work
Burn completeness, conceptually.
Why hydrogen and not something else.
Flame speed
Hydrogen's laminar flame speed is far higher than that of diesel or petrol vapour. A faster-propagating flame front means the charge is consumed sooner after ignition, so less fuel is still burning late in the expansion stroke where its energy does little useful work.
Flammability range
Hydrogen ignites and sustains a flame across a much wider fuel-to-air ratio than liquid fuels. In the lean and uneven pockets that exist in any real cylinder, that makes ignition and flame travel more reliable, which is what 'more complete combustion' means in practice.
That is where we stop. Deeper mechanism detail is proprietary group work and is not published. Nothing on this page should be read as a claim about exhaust chemistry or emissions compliance.
Next reading.
- · Technology — the PEM system specifics: stack, water treatment, control and safety interlocks.
- · Field results — the attributed evidence we hold and how it was measured.
- · Evidence review — what the published literature supports, and what it does not.
- · Four different hydrogen technologies — why enrichment is not H2ICE, a fuel cell, or hydrogen on tap.
- · Installation guide — the nine-step fitting sequence.
No projected, typical or expected fuel-saving figure is published. Actual results vary materially with engine condition, duty cycle, load profile, fuel quality, installation and operating conditions. A controlled field evaluation on your own equipment, with baseline data captured before installation, is required before any commercial projection.
Questions.
How does hydrogen combustion enhancement work?
- A small volume of hydrogen and oxygen gas, produced on demand from deionised water by an electrolyser on the vehicle, is drawn into the engine's intake air stream. Hydrogen burns faster than diesel or petrol and ignites across a much wider mixture range, so its presence in the charge helps the primary fuel burn more completely and with better phasing relative to the piston's power stroke. The engine still runs on its normal fuel — the hydrogen fraction is a combustion aid, not a fuel replacement.
Where does the gas enter the engine?
- Downstream of the air filter and upstream of the turbocharger or throttle body, through a small-bore line so the gas joins the intake air before it reaches the cylinder. Nothing is added to the fuel tank, the injectors, or the fuel rail, and no engine internals are modified.
How much gas is involved?
- A very small fraction of the total charge — measured in litres per minute against an engine breathing thousands of litres per minute. That is why this is called enhancement rather than conversion, and why the honest efficiency range published in the literature is single digits to low or mid teens rather than anything larger.
Is hydrogen stored on the vehicle?
- No. Gas is generated on demand only while the engine is running and is consumed immediately. There is no pressurised storage cylinder and no accumulated volume on board.
What does it not do?
- It does not replace diesel or petrol, it does not clear an engine defect, and it does not make an engine compliant with any emissions standard. We make no emissions-compliance, certification or defect-clearance claim.
Does it work on any engine?
- It is fitted to compression-ignition (diesel) and spark-ignition (petrol) engines within the displacement band of the chosen unit, from HydroHub™ A-450 for small engines up to HydroHub DH-Power for heavy-duty applications. A worn or poorly maintained engine is the wrong place to start — measure a baseline on healthy equipment first.
See the mechanism applied to a real duty cycle.
The gas path is the same everywhere; what changes is the duty cycle it is working against.
Mining fleets →
Haul trucks, articulated dumpers, production dozers, loaders, drill rigs and camp gensets. Dust, pit heat and remote servicing decide as much as displacement does, and carted fuel changes what a percentage is worth.
Rail & locomotive →
Two duty profiles in one sector: mainline locomotives on long steady high-load hours, and shunting, yard-switching and rail-maintenance plant on stop-start duty with heavy idle.
Waste & refuse collection →
Compactor and side-loader trucks: hundreds of stops per shift, heavy idle and stationary PTO load — the duty profile the published literature reports most room on.
Public transport & bus →
Urban route buses, coaches and midibuses. Stop-start duty with high idle fractions, depot-based servicing and public-facing smoke visibility all matter here.
Drilling rigs →
Rig power packs, mud pumps, air compressors and pad plant running long steady-state hours where fuel is trucked in and every litre carries a freight cost.
Generator sets →
Stationary diesel gensets on continuous and prime duty from 100–500 kVA — remote camps, telecom sites and standby plant fed from the set's own starting battery.
All applications — the full vertical index →·Partner program →
Continue reading.
Hydrogen combustion enhancement
What it is, how PEM gas reaches the cylinder, and what it does not do.
Engine performance improvement
Flame speed, burn completeness and load response on diesel engines.
Fuel efficiency
How to baseline and measure litres per 100 km or litres per hour.
Emissions reduction
Soot, particulate and unburnt-fuel behaviour, and how to test it.
Visible smoke reduction
Smoke opacity findings per study, with the NOx trade-off disclosed.
Remote-site fuel logistics cost
Landed cost versus pump price, and why the same percentage moves more money.
Generator-set classes
Camp, prime, standby, rental, telecom, irrigation and ship's service sets compared.
Idle & part-load duty cycles
Reefers, camp gensets and high-idle plant — where the literature reports most room.
Hydrogen with biodiesel blends
Per-study findings for hydrogen enrichment on biodiesel, NOx disclosed.
Installation guide
Nine-step fitting sequence: mounting, wiring, gas line, commissioning.
Safety & compliance
On-demand gas, no storage, alarms, shutdowns and reversibility.
Troubleshooting
Alarms, low gas output, water quality and no-start diagnostics.
Case studies & field results
Published operator data and trial methodology.
Compare PEM systems
A-450 to DH-Power side by side: displacement, output, current draw.
Does it actually work? Evidence review
The published literature, the FTC/EPA history and the ACL context.
PEM vs alkaline
Membrane on water versus caustic KOH: servicing, purity, cost.
Sizing combined gas
Why PEM and alkaline gas-volume benchmarks are not interchangeable for ICE sizing.
Four hydrogen technologies
Enhancement vs H2ICE vs fuel cell vs chemical generation.
Compared with Hydrogen Fuel Systems
Honest comparison with the Perth-based Gen alkaline range.
Compared with H2i Technology
Hardware, pricing and evidence transparency versus the Victorian supplier.
Compared with dynaCERT HydraGEN
PEM versus alkaline, published price versus dealer quote, Verra versus ACCU.
Compared with HYDI
The South Australian manufacturer: UniSA testing, field history and quote path.
AU installation, warranty & safety
VSB 14 and VSB 6, ACL guarantees and documentation to keep.
Mining fleets
Haul trucks, dozers, drill rigs and site gensets: unit selection and dust.
Marine
Workboats, charter, fishing and ship's service gensets — no gas stored aboard.
Agriculture
Tractors, headers, pump sets and farm trucks across seasonal duty.
FAQ
Answers on fitment, water, warranty, freight and duty cycles.