Fuel cell-powered 5 Series GT concept previews a revolutionary storage and refuelling system which could pave the way for hydrogen to become the alternative fuel of choice

What is it?

This is BMW’s latest hydrogen-powered concept vehicle. It is based on the 5GT and is powered by the latest-generation fuel cell stack, which is being co-developed with Toyota.

More importantly, this concept also features a new type of hydrogen storage tank. BMW has patented the technology and says it is now confident that not only is this new storage method the way of the future but also that a ‘hydrogen economy’ is the only way that Europe can disengage from fossil fuels over the medium term.

BMW has long experimented with vehicles powered by hydrogen, with its first experimental model dating back to 1984.

If you have a good memory, you might recall the ’Hydrogen 7’, based on the V12 7 Series and built in very limited numbers until 2007.

The car used a relatively conventional internal combustion engine, which, partly thanks to BMW’s Valvetronic valve intake system, could run on both petrol and hydrogen.

Since then, BMW and its hydrogen research went relatively quiet. The arrival of the first serious battery-powered production cars and scepticism about the likelihood of a ‘hydrogen economy’ has, in recent years, put hydrogen fuel cell cars on the back foot.

In 2013, BMW and Toyota signed a strategic collaboration on the development of hydrogen fuel cell drivetrains. This, BMW says, "provided fresh momentum for the development of FCEV drive technology".

BMW says its big breakthrough with this new prototype is in the hydrogen fuel tank and refuelling technology.

What's it like?

While this concept fuel cell car looks like a standard BMW 5GT both inside and out, it is very different under the skin.

Changes were made to the car’s structure, mainly in terms of crash safety for the fitting of the hydrogen tank and because the tank is bolted into the car as an integral part of the structure.

Under the bonnet sits the fuel cell stack. Fully dressed with all the ancillary components, it’s about the size of a conventional big V8. The core fuel cell stacks are a Toyota technology, with BMW supplying the new hydrogen tank, electric drive train and high voltage battery.

When running under a relatively low load the fuel cell is 65% efficient in turning the hydrogen fuel into forward motion. That’s far better than any internal combustion engine.

Under heavy load, however, the efficiency drops to 45%, which is slightly better than a typical turbodiesel engine.

The rear wheels are driven by a 199bhp electric motor via a new two-speed dual-clutch automatic transmission. A very small 1kWh battery sits above the rear axle.

The new storage tank is a huge multilayer construction. At its core is an aluminium pressure vessel which in turn is wrapped with a continuous carbonfibre-reinforced plastic filament.

This wrapped layer is around 5cm think. Around that is a radiation shield, and between that and an aluminium casing forming the outside skin, there is cavity containing a vacuum. The tank’s end caps are aluminium castings welded into place.

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Seen in isolation, the new tank looks like a noseless missile of the type you see hanging from the wings of jet fighters.

The key advance of this 5GT is BMW’s newly patented method of refuelling and storing the hydrogen fuel. They call the tank a ‘cryogenic pressure vessel’, which is designed to be filled with hydrogen cooled to –220deg C.

Super-cooling allows the tank to hold some 7.1kg of hydrogen, compared with just 2.3kg at the ambient temperature. BMW’s engineers say that 7.1kg of hydrogen equates to a real-world range of around 434 miles. The refuelling also takes around five minutes. A today’s hydrogen prices, that’s around £50.

Although this was an early engineering car, it felt tight and ran seamlessly. It’s relatively swift and the handling and ride is improved over that of the standard production model, probably because bolting the tank into the structure has improved the body stiffness. As you might expect, the car was also impressively refined.

One thing that struck most forcefully while driving was how difficult it will be for BMW's engineers to install any sort of individual character into any future fuel cell-powered executive car. Electrically driven vehicles can all be remarkably similar in the way they drive, which is smoothly, quietly and briskly.

Should I buy one?

You can’t. BMW and Toyota say they hope to have the full components set for a mass-production-capable car ready by 2020. By then the hydrogen refuelling network should be more advanced, especially in countries such as Japan and Korea.

Germany is also working to install a hydrogen network along its most heavily used routes. You get the sense that BMW and Toyota expect the argument for hydrogen power to have become dominant by then, as hopes for battery vehicles fizzle out.

Batteries, say fuel cell enthusiasts, will always be expensive, have a limited lifespan and, crucially, suffer extended recharging times. There’s also an argument that batteries are not particularly environmentally friendly.

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A fuel cell stack should last around 5000 hours or 125,000 miles, while the hydrogen storage tank should last indefinitely. This concept is the best proof yet that hydrogen will win the alternative fuel race.

Read more:

BMW's hydrogen i8 research vehicle revealed

2015 BMW 2 Series Active Tourer eDrive review

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Einarbb 2 July 2015

I understand the attractions of fuel cell cars...

...but consider the share space needed for electric cars while they top up. But petrol or diesel cars need say 5 - 10 minutes. At best an electric car 30 - 40. That implies far more space is needed for electric cars - while they're stopped and are being topped up. If we imagine 2 million electric cars on the road. Imagine how busy Petrol/Diesel stations tend to be. Imagine a comparable space where electric cars come to top up. Assume from cost point of view - clearly they will ask money for charging. And that there will be services offered like today for your car. Clearly service stations would need to have 3-4 times the space than is occupied by them today. And space especially in cities costs real lot. So I'm not entirely surprised that city planners - like the idea that an electric car can be topped up in 5 - 10 minutes like internal combustion engined car. But that's what hydrogen fuel cell cars essentially are - electric cars. The fuel cell supplying power to the electric engine, instead of the car having a stack of batteries.
topsecret456987 2 July 2015

As the North sea gas fields

As the North sea gas fields were discovered and plans to exploit this resource were made to deliver Natural Gas to the home, I can image the terror this concept created. Methane - to the home - an explosive chemical that will wipe out streets as it explodes in homes and escapes from the distribution pipes. OMG that gas network will cost billions and then we have to buy new fires/central heating systems. Whats wrong with Coal - it much cheaper and we only need to heat the rooms we use - and now we have to heat the whole house! Today the same fears paralaise us with the thought of migrating to Hydrogen, both for household and transportation needs. Yes there are things that must be done and investment made. We will all adapt and one day wonder what all the fuss is about.
xxxx 2 July 2015


Top tip - at night unplug your toaster and plug the car in. That way you pay the same price for the power. Do it after 12:00 on a timer and you'll get cheap rate, £0.02 a mile for a Leaf :- fact
xxxx 2 July 2015


Top tip - at night unplug your toaster and plug the car in. That way you pay the same price for the power. Do it after 12:00 on a timer and you'll get cheap rate, £0.02 a mile for a Leaf :- fact