January 16th, 2020 at 10:46 am
Think about the last time you saw a hydrogen fuel cell vehicle on the road, if ever. What even is a hydrogen fuel cell car? Many in the motor industry think they will outstrip battery powered EVs over the next decade so why is no-one talking about them?
Hydrogen Fuel Cell
A hydrogen fuel cell car is still an electric car but the power is generated completely differently. There is no on board battery which is topped up via a charging point, instead the power is created by chemical reactions between hydrogen and oxygen. If you combine these two elements you can produce water, electricity and heat.
The technology is still in its infancy which would explain why manufacturers have gone for the easier and probably quicker option of using batteries, under some pressure from national governments keen to meet their green deadlines and environmental targets.
From an emissions perspective, the technology is sound because the only thing to emergy from the exhaust pipe is water. Plus, the complex in-car filter system means the car can draw in dirty air as it drives along thus acting almost like a mobile air purifier.
What choice is there in the market?
The three main options are the Honda Clarity, the Hyundai Nexo and the Toyota Mirai, no coincidence that these are all manufacturers from the same part of the world, there seems little uptake from European car manufacturers at the moment although BMW and Audi are reportedly working away behind the scenes.
These are not cheap cars because, in order to create the right catalysts for the chemicals, rare metals are used which are expensive. Government grants exist to take the sting out of the forecourt price with a particular slant towards businesses. As with battery-driven electric cars, prices are expected to fall over time as the technology becomes more commonplace and easier to manufacture.
What are the benefits over battery-powered EVs?
You can refill a hydrogen cell fuel car in five minutes with enough hydrogen to take you anywhere from 300-500 miles away. The fuel is pumped in under pressure much as you would do with conventional petrol or diesel. However, very few filling stations offer hydrogen pumps with all the emphasis at the moment being geared towards battery charging points.
There is something of a stand off within the motor industry about which method is best and which is greener but many pundits still predict that battery-powered cars are just the start and they will eventually be overtaken by hydrogen cell fuel technology. It’s easy to point the finger about the way in which hydrogen is produced (it is usually made using energy drawn from fossil fuels) compared to generating electricity from solar or wind power. It also has to be taken to the filling stations presumably in a conventional diesel tanker.
What exactly is the science?
Well, you did ask. A hydrogen fuel cell consists of a positively charged anode and a negatively charged cathode that come into contact with an electrolyte. A catalyst made of platinum starts a chemical reaction that produces heat, water and electricity. Each hydrogen cell on its own would not produce enough power to move a car but they are combined together in stacks and enough energy is thereby created to power a vehicle.
Within the vehicle, hydrogen is stored under pressure in a cylinder. Hydrogen is a flammable gas so there have been safety concerns mooted about whether this is really such a good idea. But the industry has been working to a very rigorous set of safety standards and so far, there don’t seem to have been any problems with this technology from the safety dimension.
The Toyota Mira has a triple-layer hydrogen tank which is supposed to be super crash-resistant, up to five times stronger than a standard petrol tank which is made of steel. Honda uses layers of carbon fibre and aluminium to produce a similar effect to withstand intense heat and pressure.
However, there is understandably some caution. Eurotunnel does not allow any hydrogen fuel cell cars to use the route between the UK and France.
Should you buy a hydrogen fuel cell EV over a standard battery version?
There is perhaps less difference in drive and external styling with a hydrogen cell car compared to a conventional engine vehicle as opposed to an electric battery version. This is because hydrogen fuel behaves in the vehicle in a way that is perhaps more similar to conventional fossil fuels than the battery alternative. But the car makers admit this technology is not for everyone largely because the infrastructure is not there to support it. Tax incentives seem to be aimed at business buyers rather than private motorists so its likely that this hydrogen power is still a way off yet and is perhaps a longer-term solution than the easily accessible battery versions. This is how many experts in the industry predict it will go with the development of hydrogen fuel cell vehicles being driven by the business sector in the early days as they have the pocket to do it.
There must be something in it however as the AA has already started work on recovery processes to get a hydrogen vehicle started again at the roadside if it is out of gas. They are running this alongside their EV charging vehicle which also has on board a hydrogen dispenser able to top up hydrogen fuel cell cars and provide around 40 miles driving, enough to see them to a fueling station.
So what are they like to drive?
The first impression from a reporter working for the BBC is quiet.
Range anxiety is still touted as the biggest concern over hydrogen cars, more of an issue than standard battery EVs which already have more charging points. It would seem manufacturers are reluctant to invest more time and money until they are sure about uptake. Consumers are reluctant to put a toe in the water unless they feel there is sufficient infrastructure in place, it’s rather a vicious circle.