Unlike hydrogen, with its explosive properties, ethanol is just as easy to handle as today's liquid fuels
Matt Prior
23 September 2016

When the experimental Airlander airship – the world’s largest aircraft – took a nosedive at Cardington on a test flight the other week, there’s a reason why it didn’t do so in a fiery ball.

It’s filled with helium, an inert, lighter-than-air gas whose most sinister effect is making your voice squeaky, as opposed to hydrogen, the lightest element whose sometimes troublesome characteristic is its explosiveness when exposed to a naked flame. Or perhaps some sunshine. Or sometimes just for the fun of it.

The excellent thing about hydrogen, mind, is that when it’s combusted it gives off water, which is not, unlike conventional fuels, a greenhouse gas. Otherwise, hydrogen – a hugely tempting source of automotive power though it is, because of its tremendous potential – can be a right pain.

It has to be handled safely. That’s no big deal, but doing so isn’t cheap. Hydrogen can make some metals brittle, limiting what you can store it in, but you can put a pressurised carbonfibre tank in a car and it won’t let go even in an extreme crash. Neither do they leak, like those in some early hydrogen-powered cars, which couldn’t be parked inside; a slow seep could fill the upper part of your garage with highly explosive gas. Then you could stroll in and switch on the lights…

These are problems past, and the gradual emergence of hydrogen fuel cell cars is proof that it can be safe. Now, for the oft-mooted fuel of the future to become the fuel of the present, you’ve just got to make it available in more than just eight places in the UK. Which, given the safe storage requirements, isn’t exactly the work of a moment.

All of which, it seems to me, has been rather holding back the fuel cell vehicle. Until, that is, I met one the other week that doesn’t use raw hydrogen in the cell but creates it from onboard bio-ethanol instead. A remarkably good idea. Perhaps.

The Nissan e-Bio fuel cell concept, currently being tested in a van, is being developed for South America, where ethanol is sold in most filling stations. So that’s the first hurdle cleared: you can refill it anywhere. It’s no more difficult to handle than other liquid fuels, so there’s no hugely expensive carbonfibre tank under massive pressure, just a 30-litre fuel tank good for a 250-mile range.

Problems? Hell, yes. Using ethanol in a fuel cell isn’t greenhouse gas-free. But people in labs say that’s offset by growing the crops from which the ethanol is made; you’re not releasing it from fossil fuels. And because those crops are food ones (like sugar cane) and the ethanol is a by-product, it’s not stealing land for food production, unlike early biofuels.

And it doesn’t make much power. For now, the cell in Nissan’s development van gets by with 5kW – just under 7bhp, or about as much as a rental kart. Instead of fuelling on demand, then, it’d tick over at 7bhp all the time to charge a battery, which provides peak power when you need it. It’s more range extender than drive provider.

But, still: a more powerful cell, an extra pump at the filling station. These things seem trifles compared to the alternatives. It seems to me that future fuels just got another option – one with tremendous potential. 

Our Verdict

Nissan e-NV200

We drive Nissan's van-based five and seven-seater, which is claimed to be the world's first all-electric MPV

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23 September 2016
and will remain that way until the US Bureau of Land Management gets a grip.

23 September 2016
That growing fuel on land, doesn't impact prices for land - hence ultimately price for food. Such claims always appear to be economically unsound. Moreover clearly impractical at the required scale -- given the enormous environmental impact from the massive amount of land required if grown fuel would become widely used. In short net environmental impact clearly negative.

23 September 2016
not practical for the whole world as there is not enough land available never mind water to grow the crops required as a full substitute.They have used ethanol for many years in brazil so is ok for them.

23 September 2016
Vegetable oil.

23 September 2016
fadyady wrote:

Vegetable oil.

The military use diesel/ jet fuel in fuel cells for low power applications already where quietness is important.
There are fuel cells available for keeping batteries charged in motor caravans etc that run on propane. They are very expensive to purchase compared to a generator and only produce low power but have the advantage of virtually no noise where a generator is not allowed.

All of these non hydrogen fuelled fuel cells have to first convert the primary fuel into hydrogen by steam reformation or similar which of course produces some pollution just as making hydrogen from any source does.


23 September 2016
This is interesting, in that perhaps it points to a future where cars are powered in a variety of ways depending on what is best for the local region. We are moving away from the one-size-fits-all approach where burning petrol or diesel creates - all things being equal - the same level of pollution wherever you are on the planet. We all know that the eco credentials of battery powered cars vary drastically because battery cars are only as clean as their electricity source, so your BMW i3 could be coal powered or nuclear powered depending on where on the planet you live. South America is another specific case, so why not make use of their local resource? Maybe in the future manufacturers will supply vehicles that can take a variety of power sources to take account of this.

23 September 2016
It isn't the case that ethanol is a mere by product of food production, it has a direct impact on food costs. My other car is a horse and ever since ethanol started to be an additive in US gasoline I have seen the price of a bag of grain almost triple.

23 September 2016
I thought the entire point of a fuel cell is that energy can be stored in (potentially) cheap, light hydrogen rather than expensive, heavy batteries. This concept sounds like the worst of all possible worlds.

23 September 2016
fossil fuels are natural...the only issue is time.

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