2024 BMW iX5 Hydrogen review: Quick drive

Hydrogen-powered vehicles have long been promised as the 'silver bullet' for the future of cars, the no-compromise, near-zero-emissions propulsion type to complement electric cars – or replace them entirely.

While fully-electric vehicles have flourished in that time – largely owing to Tesla, the company that arguably proved battery-powered cars could be more than milk floats – hydrogen-powered vehicles have remained a niche offering.

Using a fuel cell to turn pressurised hydrogen gas into electricity promises driving range and refuelling times similar to petrol cars, with the zero tailpipe gas emissions and smooth driving experience of a battery-electric vehicle. But high prices, a lack of refuelling infrastructure, and little manufacturer commitment have held them back from mass appeal.

Car giants such as Volkswagen have turned their back on the technology, but others – including BMW – believe hydrogen fuel-cell and battery-electric cars can co-exist.

After signing a deal with Toyota to collaborate on hydrogen technology more than a decade ago, it has rolled out its latest prototype – based on the BMW X5 SUV – to evaluate the suitability of the technology in the real world.

BMW says it will decide by the end of this year if it will put a hydrogen car into production, though if the green light is given, the technology would not appear in one of the company’s showrooms until late this decade.

As part of a global tour – which has included visits to snowy Sweden and the UAE desert – a pair of BMW iX5 Hydrogen prototypes have arrived in Australia, and Drive was invited to the former Holden proving ground in Lang Lang, south-east of Melbourne, to take it for a spin.

Given the rapid advancements in electric vehicle technology – and the expansion of the recharging network – it’s understandable to question the need for hydrogen power.

BMW says there is room for the two technologies to co-exist, with battery-electric power suited to smaller passenger cars and urban transportation that does not need to cover long distances regularly.

Meanwhile, hydrogen fuel-cell vehicles – which can refuel in three to four minutes – would include utes, vans and heavy trucks, and the technology suits buyers unable to charge an electric car at home, who need to travel long distances on short notice, or tow regularly.

Infrastructure is the biggest barrier to the rollout of hydrogen fuel-cell vehicles (FCEVs, for short), but the European Union has committed to operating more than 600 hydrogen refilling stations by 2030 – including one in each large city, and every 200km on the open road.

There are few places to refuel a hydrogen-powered vehicle in Australia – among them, Toyota’s Altona head office in south-west Melbourne, where these iX5 test cars topped up their tanks – but there are plans to expand the network.

BMW cites studies that claim it is cheaper to build a mix of hydrogen refilling stations and EV charging plugs than go all-in on battery-electric cars, due to the upgrades required to the electricity grid to power the charging stations needed to accommodate them.

If it deems the rollout of infrastructure suitable – and the technology worth the effort – BMW says it could have its first hydrogen production car in overseas showrooms, before building a broader line-up in the 2030s.

Remove the blue accents and Hydrogen decals, and there would be few clues that this is more than a petrol or diesel BMW X5.

The BMW X5 is available as a plug-in hybrid – and it shares its underpinnings with the BMW iX battery-electric SUV – so fitting a hydrogen fuel-cell drivetrain doesn’t require a significant structural overhaul.

Think of a hydrogen fuel-cell vehicle as like any other electric car. But instead of storing all of its energy in a massive battery pack, most of the energy needed for propulsion comes from pressurised hydrogen gas stored in tanks, which is converted to electricity in a fuel-cell stack.

There are tailpipe emissions, but it is pure water vapour, which BMW says is so clean and distilled you wouldn’t want to drink it (but you technically can).

BMW has elected to use hydrogen fuel-cell technology, rather than feeding hydrogen into an internal combustion engine, as Toyota is experimenting with. The company says this ‘hydrogen combustion’ technology is too inefficient, and would drink the same amount of hydrogen in 300km as a fuel-cell vehicle would in 500km.

How does the fuel cell work? Time for a quick chemistry lesson.

Each of the fuel cells consists of a membrane coated in a catalyst layer. When a hydrogen molecule hits the catalyst, it’s split into a proton and an electron.

While the proton is passed through the membrane – designed with holes so small only hydrogen protons can fit through – the electron takes a detour to run through an electrical circuit, where it becomes the electricity needed to power the electric motor that drives the car.

The electron returns to the proton, where – in layman’s terms – the pair meet with oxygen from the ambient air, and combine to form water (H₂O), emitted from the car as a vapour.

The hydrogen fuel-cell stack – developed by Toyota, and shared with the Mirai sedan – develops 125kW.

BMW says many of the components within it, such as cooling systems and compressors, are not dissimilar to parts used in petrol and diesel vehicles, which car companies have learnt how to make cheaply in large numbers.

The fuel cells are aided by a battery with the capacity of about three Toyota RAV4 Hybrids – less than 5kWh, the company says – which can supply up to 170kW of additional power on demand.

The electric motor is sourced from the BMW iX and – you guessed it – develops 295kW, sent to the rear wheels.

Six kilograms of hydrogen is stored across two tanks – one along the central tunnel of the car, and the other where the fuel tank would previously reside – at a 700-bar pressure (for context, the pressure in your car’s tyres is about 2.5 bar), and BMW says the iX5 has passed all the same safety tests as the regular version.

The German car giant says the iX5 Hydrogen is capable of accelerating from 0–100km/h in less than six seconds – comparable with many petrol hot hatchbacks – with a 185km/h maximum speed, and a driving range in European WLTP testing of up to 504km.

And unlike a battery-electric car, refilling the tanks takes three to four minutes. BMW says the iX5 is comparable in weight to a plug-in hybrid X5 – at about 2.4 tonnes – and is approximately 100kg lighter than what an electric X5 would weigh, if one existed.

Blue accents – and hydrogen fuel-cell branding on the dashboard – are some of the only clues this is the iX5 Hydrogen, not a petrol or diesel X5.

It is based on the pre-facelift version of the current X5, so it gets a pair of 12.3-inch screens with older BMW software – not the 14.9-inch iDrive 8 touchscreen of the newest model in showrooms now – and firmly padded but comfortable leather seats.

There are all the same amenities as the regular X5 – climate control, USB ports, the latest smartphone connectivity – and plenty of space for passengers, though the middle-rear passenger is required to straddle quite a large tunnel.

A ‘Hydrogen Fuel Cell’ label – and a ‘% H2’ gauge – are giveaways of what you’re driving.

While we’re talking about differences, it’s worth pointing out the pair of iX5s shipped to Australia – as well as other vehicles on the global fleet, which have clocked up more than one million kilometres to date – are hand-built in Munich, rather than produced on the same production line as petrol and diesel models in the US.

The driving experience is possibly the least exciting part of the iX5 Hydrogen, as it is much like any normal battery-electric car – and what an electric BMW X5 would feel like, if one existed.

We only had a few kilometres behind the wheel around the ‘ride and handling’ track at the former Holden test track – which simulates an undulating and winding Australian country road – and with multiple passengers on board, pushing the car’s mass close to three tonnes.

Straight-line performance is brisk, as the 295kW power output would suggest, with the shove in the back when flooring the accelerator pedal we’ve come to expect from electric cars.

Sport mode unlocks maximum power, as well as synthesised driving sounds – known as IconicSounds – which build on what is otherwise a quiet experience, aside from some unavoidable tyre roar and wind rustle, as well as a dash of electric motor whine under acceleration.

The iX5 Hydrogen can’t hide its 2.5-tonne mass – plus passengers – in corners, but the Pirelli P Zero sports tyres deliver good grip, and the steering is precise and reassuringly heavy, albeit a touch artificial and not quite natural in its feel.

Air suspension is fitted to the hydrogen test vehicles, given their mass and 22-inch alloy wheels.

It translates to a supple ride over small imperfections in the road, and reasonable composure at higher speeds over undulations in the road, though again it’s clear that in the form we tested it, the iX5 is the weight of two BMW 1 Series hatchbacks.

There is some wheel slip off the mark, and the rear-wheel-drive layout – as the rear of the car wants to step out – is evident when driving enthusiastically, though at more sedate speeds common to a public road, not a closed test track, the iX5 delivers safe and secure roadholding.

Paddles on the back of the steering wheel allow for control of the regenerative braking system – which uses the electric motor to recuperate energy and slow the car down when decelerating, as with electric cars – and we’re glad to see a ‘one-pedal’ mode capable of bringing the car to a halt without touching the brake pedal.

Hide the hydrogen fuel cell badges – as well as the hydrogen tank level gauge – and you would struggle to tell the iX5 Hydrogen apart from a normal battery-electric car. That is a compliment, not a criticism.

In theory, hydrogen fuel-cell cars promise the best of both worlds: the quiet driving and emissions of an electric car, with the driving range and quick refuels of petrol and diesel vehicles.

The BMW iX5 Hydrogen is a great example of the breed, offering the performance expected of the German badge – without feeling like a science experiment.

However, there remain the roadblocks that have slowed the rollout of hydrogen cars over the past two decades (or more) – most notably, they’re expensive to build, and there still aren’t many places to refuel them.

BMW says it thinks it can get hydrogen fuel-cell cars to the same price as battery-electric vehicles, even with upcoming advancements in battery technology.

And there is reassuring progress being made in Europe in constructing a network of hydrogen refilling stations the German giant envisions would be led by demand from heavy trucks, onto which passenger cars could piggyback.

Of course, a hydrogen car available for sale in a BMW showroom would be at least five years away, and while Toyota and Hyundai sell hydrogen fuel-cell cars in Australia, they’re usually found on select business and council fleets through a lease, not for outright purchase by the public.

If – and only if – the hurdles can be cleared, hydrogen fuel-cell vehicles represent an enticing petrol or diesel replacement for Australians that love to tour the country, caravans or boats in tow.

But a lot must happen before then, and only time will tell if hydrogen fuel-cell vehicles can survive the tsunami of cheaper, longer-range and faster-charging electric cars headed our way.