Car manufacturers often trial new car concepts, sometimes to gauge potential interest or to simply show that they are being innovative. However when it comes to hydrogen fuel cell cars, it seems like there has been a range of cars that were unveiled, discussed a lot at the time, then almost forgotten about. Whether it’s the GM HydroGen4, the BMW i8, BMW Hydrogen 7, Honda Clarity or Mercedes-Benz F-Cell, we’ve often wondered where they are now, and whether they’ll compete with the Toyota Mirai and upcoming Hyundai Nexo (which are being actively produced). Let’s find out!

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GM HydroGen4

Over a decade ago in 2007, General Motors unveiled “Project Driveway” which was both a marketing and manufacturing trial program for hydrogen cars. It would involve a range of hydrogen cars being driven by people living in parts of California and New York. The GM HydroGen4 was part of this pilot, and it was unveiled in the IAA show in Germany.

The GM HydroGen4 car itself was a crossover SUV vehicle based on the Chevrolet Equinox body (but naturally powered by hydrogen fuel cells not gasoline combustion engines):

The GM HydroGen4 car, from ResearchGate.net

Only 170 HydroGen4 cars were ever produced according to research, all between 2007 and 2008. More than 100 of these were given to the public as part of Project Driveway. The car itself had an interesting specification:

  • A 93 kW fuel cell system, which isn’t much less than the 113 kW fuel cell in today’s Toyota Mirai
  • 2,010 kg weight, around 230 kg heavier than the Chevy Equinox (gasoline version)
  • Contained three Type IV CGH2 storage tanks, each with a 4.2kg capacity (hence they can store 12.6 kg of hydrogen). This compares to the 10 kg overall capacity of the Toyota Mirai.
  • A 1.8 kWh battery, higher than the 1.6 kWh battery in the Mirai.
  • A 160 kmph (100 mph) top speed
  • A 320 km (198 mile) range, much lower than the Mirai’s 502 km (312 mile) range compared to the higher capacity hydrogen tanks and battery packs.

GM don’t have any plans to bring HydroGen4 back into active production, especially since it was built around an old model of the Chevy Equinox. However their 2017 press release implies that they are planning on being a major player in the hydrogen vehicle market, but possibly aimed more at industrial and army fuel cell vehicles than fuel cell cars:

The company will display its Silent Utility Rover Universal Superstructure (SURUS), a flexible fuel cell electric platform… [which] could be adapted for military use.

Fuel cell technology represents a key piece of General Motors’ zero emission strategy. It offers a solution that can scale to larger vehicles with large payload requirements and operate over longer distances.

BMW Hydrogen i8

German luxury car manufacturer BMW unveiled their BMW Hydrogen i8 in 2015, a hydrogen fuel cell adaptation of the luxury BMW i8 coupe. It looks pretty bad-ass, leading to Top Gear describing its “Mad Max-spec bodywork” as “pure evil”:

A side view of the BMW Hydrogen i8

This batmobile style car is worth seeing in the following video:

The BMW Hydrogen i8 was revealed to the World in one of BMW’s Group Innovation Days (based in France) in 2015, and it is based on a BMW 5 GT-Series model from 2012. In terms of more detailed specifications, there’s not tonnes of information out there but we’ve been able to find out the following:

  • It has an estimated range of around 500 km (310 miles).
  • This car was built in partnership with Toyota, who helped with the fuel cell stack.
  • It can do 0-100 kmph (i.e. 0-62 mph) in 6 seconds.
  • Total system power is around 250 bhp.
  • A max speed of 200 kmph (124 mph)

This Hydrogen i8 was also more of an R&D exercise for BMW, although they are aiming to produce consumer-level fuel cell cars for sale by 2021.

BMW Hydrogen 7

The BMW Hydrogen 7 was made from 2005 to 2007 and it was one of BMW’s first attempts at creating a hydrogen car. This model was based off the 760Li and it actually had a combustion engine (instead of fuel cells):

A BMW Hydrogen 7 outside an car event, from Wikipedia.org

This car’s 6L V12 engine was actually modified into a bivalent engine which could accept both gasoline and hydrogen, and burn either. Only 100 units were ever produced in the two year ‘trial program’ for this vehicle, and it is thought that the Hydrogen 7 was scrapped by BMW partly after the EPA’s negative findings. The EPA said that the vehicle was not entirely greenhouse-gas-emission free, and also that the efficiency of the car was quite low: 16.9 mpg (US) with gasoline and just 4.7 mpg (US) with hydrogen!

A large part of this poor efficiency (worse than many trucks/lorries!) is that gasoline and hydrogen have different energy densities, meaning burning (combusting) them both in the same engine will lead to inefficiencies for at least one of the fuels. Also fuel cells are generally a more efficient method for obtaining electricity from hydrogen.

Nonetheless, this was an interesting attempt at making a car, and some interesting facts for it are:

  • BMW hand-picked certain people who would be able to drive these cars, according to the original press release: We will identify people we want to see in those cars because we think they would be ideal ambassors for hydrogen fuel. Oscar winning director Florian Henckel von Donnersmarck and EU car rental boss Erich Sixt were amongst the recipients.
  • The gasoline version of the car (the 12-cylinder 760Li) had a base price of $118,900 in 2005. No financial figures were made public for the BMW Hydrogen 7, although it is thought that the hand-picked individuals who received the car would have to pay a monthly fee to lease it.
  • Whilst the act of combusting hydrogen can be emission free (in terms of greenhouse gases), the EPA found that the various oils and liquids in the system to support gasoline fuel meant that burning hydrogen fuel also released some level of harmful emissions into the atmosphere.
  • The hydrogen fuel was stored in liquid form which complemented the combustion engine better (compressed hydrogen fuel is more suited for fuel cell based systems). It was stored in a large 170 litre (45 gallon) tank. This required a large amount of cryogenic cooling, however, to keep the hydrogen as a liquid. This isn’t an efficient process on a car and due to a few reasons, the hydrogen would disappear out of the tank in 12-14 days. In other words, the ‘shelf life’ of the hydrogen in the Hydrogen 7 car would be less than a fortnight.
  • The 6L V12 engine offered 250 bhp of power.
  • The BMW Hydrogen 7 could do 0-100 kmph (0-62mph) in a relatively slow 9.5 seconds.
  • The overall kerb weight of the car was 2,300 kg (5,100 lb) - around 10% more than the base 650Li model.

This was a fairly interesting pilot that received a fair amount of press at the time, but the poor efficiency and lack of hydrogen refuelling infrastructure hindered it a lot. Nonetheless, the idea of using internal combustion engines for either gasoline or hydrogen is interesting: it could lead to fairly cheap cars (due to the existing support in the supply chain for building ICEs) that offer somewhat ‘green’ credentials.

Honda Clarity

Okay, so including the Honda Clarity in this article of “ghost hydrogen cars” might seem unfair: because the Clarity is available to lease in certain areas of California. But the Clarity has an interesting history, and it’s still only available in limited quantities - so we thought that it’s worth including here.

The Clarity began life as the Honda FCX Clarity in 2008, a hydrogen fuel cell car which had a large sedan style body. It was produced in Japan, but originally leased to customers in America before being extended to Japanese customers in November 2008. The FCX Clarity was produced almost on demand between 2008 and 2014, but due to the lack of hydrogen fuelling stations being a big blocker, it is thought that only around 60 units were ever leased (46 to American customers, the rest to Japanese and European customers).

A marketing image of the Honda FCX Clarity from a Honda press release

The FCX Clarity had 134 bhp and a range of 369 km (240 miles) based on a full hydrogen tank which stored away just over 4kg of compressed hydrogen. Honda were originally quite confident about the FCX Clarity, with media reports from 2009 saying that they were aiming to build fuel cell cars at high production levels (and with a price comparable to gasoline cars) by 2020.

However in the end the FCX was scrapped in favour of the overhauled and re-designed Honda Clarity. This particular model is a lot more active (in terms of future plans) than any other car we’ve spoken about so far, going as far as having an official sales page on their website with prices: $369 per month for a three year lease. The Honda Clarity also comes in PHEV and BEV form, so Honda are using the Clarity designation for their current green car efforts.

The Honda Clarity Hydrogen version was unveiled in 2016, with deliveries going to customers in 12 dealerships across California throughout 2017. It’s also a sedan style car:

Promotional image of the Honda Clarity Hydrogen model from 2018

Its spec and other info are below:

  • The $369 per month lease brings $15,000 of free hydrogen fuel with it.
  • The Honda Clarity has a 590 km (366 mile) range, lower than the Toyota Mirai’s range of 502 km (312 miles). This EPA-verified range makes the Clarity the longest range zero-emission car on the market right now.
  • A kerb weight of 1,875 kg (4,134 lb) - a marginally higher weight than the Mirai.
  • A 138 bhp motor, a little higher than the 134 bhp motor of the FCX Clarity.

The Clarity is an interesting car because it has a lot going for it in terms of having the longest range of any green car, and it’s not too expensive at $369 per month including essentially free fuel over the lease period. However it has never been produced in massive quantities, and the 2018 model is listed as “sold out” with no immediate mention of when the 2019 version will be available.

Honda’s public statements do seem positive about hydrogen technology, though, so it’ll be interesting to see if the Clarity Hydrogen is scaled up in production to meet the slowly-but-surely rising demand for fuel cell cars.

Mercedes-Benz F-Cell

The Mercedes-Benz F-Cell, produced by parent company Daimler, is a hydrogen fuel cell car but with PHEV-type capability: as in, the fuel cells will charge the battery pack as with other hydrogen cars, but you can also plug-in the F-Cell and charge it as you would with a PHEV/BEV:

Marketing image of the Mercedez-Benz F-Cell being charged up indoors

The version shown above is based on the Mercedes-Benz B-Class car, which was unveiled in 2010. Further adaptions were made in 2017-2018 to the plug-in capabilities. However there was an earlier F-Cell car which was based on the 2002 A-Class, and had quite a limited range 100 miles (161 km) and top speed (82 mph/132 kmph).

In terms of the current F-Cell version, it sounds quite interesting and Mercedes-Benz are keen to list its selling points on their website, including that it has four different operating modes:

  1. Hybrid: the car is powered by both energy sources, with the fuel cells used most of the time whilst the battery pack’s power is used during power peaks, just like standard hybrid cars.
  2. Fuel cell: just the power generated by the fuel cells are used, and the battery isn’t relied upon (and instead is actively charged up by the fuel cells). Only hydrogen is consumed at this point, and this mode is ideal for highway driving.
  3. Battery: the 13.5 kWh lithium-ion battery is entirely used; the fuel cell is not, and thus no hydrogen is consumed. This mode is used more during smaller local trips.
  4. Charge: priority is given to charging up the battery pack, possibly to build up reserves before a long level. In this mode, the fuel cells and hydrogen are used more than in the ‘hybrid’ mode.

The Mercedes-Benz F-Cell has been around for almost two decades in some form, but it’s always been low-unit production. No exact figures have been published, but it’s possible that just 100-150 have been leased out to customers over the 17 year lifespan. Daimler do seem interested in hydrogen as a fuel source for cars, and Germany has better hydrogen infrastructure than many countries - but it remains to be seen whether production of the F-Cell will ever be scaled up.

Conclusion

Many car manufacturers are still clearly in the proof of concept stages for their fuel cell cars, either focussing more on electric cars or simply waiting until after 2020 to scale up their hydrogen car plans.

This is because whilst electric car technology matured and started falling in price 5-10 years ago, hydrogen/fuel cell technology still isn’t quite there. However manufacturers do seem hopeful that there’ll be a ramp up in demand within the next few years, so it’ll be interesting to see if the manufacturers covered in this article (and others) will scale up production of their fuel cell cars between 2020 and 2025. We suspect that they’ll be watching the Toyota Mirai and new-to-the-market Hyundai Nexo will great interest.