Detroit show: Audi outs h-tron quattro concept

AUDI has revisited the possibility of hydrogen fuel-cells as an alternative automotive energy with a Detroit motor show concept that has the range, performance and refuelling time of combustion engines, but produces zero emissions.

Based on the e-tron quattro concept that broke cover at the Frankfurt motor show last year, the h-tron quattro concept has an additional hydrogen fuel-cell that generates 110kw of electrical energy and another 100kW on tap from a temporary lithium-boost battery for sub-7.0 second 0-100km/h performance.

Critically though, while the h-tron has the performance and environmental benefits of the full-electric version, its hydrogen fuel tank is far faster to fill than charging a battery, taking just four minutes for a full top-up.

At its core, the h-tron quattro uses a fuel-cell, which can produce up to 280 volts and with recent advances in the technology is 60 per cent efficient. For comparison, the best figure an internal combustion engine manages is around 40 per cent thermally efficient.

After refuelling, the h-tron has a range of up to 600km, which is also comparable to more conventional combustion engine-powered vehicles, but a roof-mounted solar array can extend that figure while driving.

Its 210kW and 550Nm of torque is fed to all four wheels via a motor on each axle for typical Audi quattro traction and road-holding, and was first demonstrated in the Audi A7 Sportback h-tron quattro.

While other car-makers have experimented with cryogenic storage, the Audi's hydrogen is stored at normal temperatures, using extreme pressures of 700 bar to hold up to six kilograms of the gas in three separate composite-material tanks.

That may not sound like much but hydrogen is much lighter than air and the h-tron needs just one kilogram of the gas to travel 100km.

The trio of bottles are different sizes and distributed around the h-tron's structure so that no interior space is sacrificed – an advantage of the flexible MLB evo platform on which the h-tron is based, says Audi.

In addition to the performance practicalities, the h-tron also offers other handy features such as a cabin that can accommodate four occupants in sporty seats with ample headroom, as well as 500 litres of luggage or 1610 litres with the rear seats folded.

The German car-maker is not yet talking about a production version and, although Audi Australia product communications executive Shaun Cleary told GoAuto the company was intrigued by all alternative energy solutions, he said a production hydrogen model would be hard to justify in Australia until a local refuelling network was implemented.

“We are definitely interested in all new alternative drivetrain technologies with the e-tron (A3) on sale since August last year, and we think our customers are also interested in these forward-looking alternative technologies, but obviously the infrastructure has to support it and, I think it's fair to say, in Australia, it's not quite there,” he said.

But Mr Cleary said that the hydrogen network had every chance to become established in the same way as the electric recharging network is growing, and projects like the A7 h-tron and h-tron concept are examples of the company's continued research into multiple power sources.

“It is building on the EV side to support the e-tron and that's not to say there won't be a similar level of support in the future for hydrogen cars... It's definitely something we've been looking at for some years.” While Australia lags behind other parts of the world in alternative energy, some European countries including Germany are taking on the responsibility of pioneering hydrogen power.

The Audi e-gas facility in Werlte, Germany produces hydrogen using only renewable wind power for a sustainable and environmentally sensitive source of power for fuel-cell vehicles.

In an additional stage, the facility forms synthetic methane from the hydrogen for use in Audi's experimental A3 g-tron and A4 g-tron vehicles.

Independent stations such as the H2 facility in South Tyrol, Italy produce hydrogen from wind energy during off-peak electricity periods, ensuring the resulting fuel source is reasonably priced as well as environmentally sound.