Huge investments and technical knowledge are being poured into making hydrogen our future transport fuel

The next "great leap forward" in transport is to hydrogen fuel cell vehicles.

Australia's $74.5 million Future Fuels Fund and the Australian Hydrogen Council is strongly committed to steering the country down this path, particularly as a transport fuel for light, medium and heavy-duty trucks, buses and SUVs.

And in various places around the country, the revolution has quietly begun.

In August this year, billionaire WA miner Twiggy Forrest had his company Fortescue Metals sign an agreement with Hyundai to enter a five-year partnership with the CSIRO for the developing new bulk hydrogen transport capabilities.

It is also building its own refuelling facility at Christmas Creek in WA, and turning its entire coach fleet - which takes miners out to sites - to hydrogen.

In Port Kembla, a startup called H2X aims to be building hydrogen cars by the end of next year. It will call its first local vehicle the "Snowy".

The technology is so new, and car companies so conservative in their approach, that the only option is a lease. By the middle of this year you will be able to lease either a Hyundai Nexo or a Toyota Mirai. Hyundai wants to price the Nexo lease cost at about the same as an equivalent turbo-diesel SUV of the same size.

The factory lease is not an uncommon way of testing a new and unfamiliar product with consumers. Honda did the same to market-test its Clarity fuel cell electric car in California in 2017.

It's a way for the factory to closely monitor all the vehicles, their service and maintenance records, and pick up any small issues before they become big issues. It's basically a safety net for both the factory and the consumer.

You wouldn't. Not quite yet, at least. Not until more refuelling stations are commissioned.

Having just one refuelling station in Sydney (at Hyundai's headquarters), one in Canberra and another in Melbourne (at Altona) is downright inconvenient to say the least.

There's hundreds more electric vehicle recharging stations than there are hydrogen refuelling stations.

But once the refuelling issue is solved, as a package, the hydrogen vehicle appears to offer intrinsic advantages over an electric vehicle, especially for Australia's rural and remote areas and long-distance haulage.

Both achieve the same end goal of zero emissions.

Hydrogen's key advantages are the fast refuelling time, the easy repurposing of existing refuelling infrastructure, and the fact that the fuel cell car doesn't have to lug around a plug-in electric car's heavy battery pack.

Given the limitations of batteries as a (weighty) power source, the technical sophistication and user-friendliness of fuel cell cars offers greater promise for long-distance environments such as Australia's.

Hydrogen is pumped into the car's fuel tank in a staged way, at very high pressure, but the fill time at the bowser is very quick - usually between four to six minutes. Even at a fast-charge station, the best electric cars take 20 to 30 minutes minimum - if there's a spare charge bay available.

When an electric car's lithium-ion battery is part depleted and then fully recharged, it loses a tiny amount of its storage every time (except for the Audi e-tron, which uses a very clever cooling system to avert this issue).

Hydrogen is just a volume product, feeding an onboard chemical reaction; you can top up and go without any detrimental effects.

Yes, but so are most hydrocarbon-based fuels. Hydrogen suffered its worst PR disaster when the Hindenburg airship exploded in 1937. More recently, hydrogen service stations have also leaked and ignited. But production fuel cell cars like the Hyundai and Toyota have a five-star crash safety rating.

The advantage with hydrogen is that, like Freddie Mercury, it wants to break free. It is such a light gas that, with the slightest of leaks, it wants to dissipate into the atmosphere.

To compare, when LPG (a mixture of butane and propane) escapes, it is heavier than air, so it sinks and pools.

This is where it gets tricky, because the cost of hydrogen is tied to the electricity required to produce it using electrolysis - the splitting of H2O into hydrogen and oxygen - and the compression of the gas thereafter.

If the fuel is processed and stored when power is cheap, then the cost is low (apart from the compression/storage). But if demand exceeds supply and it has to be made when grid power costs are high, it becomes expensive.

And only by producing "green" hydrogen - that is, using renewable energy - does it make any sort of sense.

Late last year, a kilogram of hydrogen cost $US13 at an independent Californian refuelling station. That makes the cost of filling a Nexo at over $A100 for a driving range of around 600 kilometres.

But equally, making the fuel on site using solar-derived battery power stored after a hot summer's day would be dirt cheap.