It’s Betamax versus VHS all over again.
Despite the recent growth in EV sales, one thing hasn’t changed: the question of which alt-fuel is ultimately the best for buyers, the market, and the planet.
The current state of play is fairly obvious. The rivalry between battery-electric vehicles (BEVs, or what most think of simply as EVs) and hydrogen fuel cells electric vehicles (FCEVs) still hasn’t thrown up a clear winner on the technology and production front, but it’s BEVs that have stolen a march on hydrogen in the hearts and minds of buyers and brands alike.
Tesla has done much to thrust the virtues of purely-electric motoring into mainstream consciousness with the Model 3 and Model Y, and Nissan has previously been selling stacks of Leaf EVs across the world, and now has its Ariya SUV in the mix.
BYD, Volvo, Mercedes-Benz and a handful of others have all brought their own electric cars to market, while only two carmakers have had a production hydrogen vehicle on sale for a meaningful length of time: Toyota with the Mirai – is now into its second generation – and Honda with the now defunct Clarity FCEV.
Toyota in particular has been vocal in committing to offer a variety of powertrains, including combustion engine, BEV and FCEVs so buyers can choose the right one for their driving needs. BMW has adopted a similar sentiment.
Even Kia Australia has put distance between itself and corporate cousin Hyundai on the subject. In Kia’s view, electric tech is rapidly approaching the point where hydrogen will have few advantages over it. Are they right?
Virtues and vices
So what exactly are the pros and cons of each tech, which one has a greater number of positives versus negatives, and which is the best fit for Australia?
Let’s start with battery-electric vehicles. The advantages of BEVs are quite well-known by now, and the rapidly-increasing introduction of new electric models is no accident. There are several reasons why many of the world’s carmakers are starting to wheel out entire line-ups of battery-electric cars, here are just a few.
- EV technology is fast approaching maturity, with cost parity with combustion-engined cars possible within the next five to 10 years.
- Present-day BEVs provide an acceptable range for the average motorist, given the average workday commute distance of 40-70km. Most EVs right now will take you well beyond 350km before battery capacity becomes a concern. A growing number of urban and suburban truck and bus fleets have adopted BEVs in Australia.
- Energy distribution infrastructure is everywhere in metro areas, with more public fast chargers popping-up in cities and along highways.
- Even without a dedicated faster wall unit, every electric car on sale today can be trickle-charged from an ordinary household outlet – which is most preferred, cost-effective and convenient as it fills up overnight without needing to stop at a fuel station.
- A growing number of electric cars are adopting rapid DC charging capabilities using 400- and 800-volt class architectures, reaching speeds up to around 250kW. So, a 10-to-80 per cent charge can take just 20 minutes, instead of 40-60 minutes. If that’s still a hassle, Chinese automaker Nio is rolling out stations overseas that swaps the EV battery for a near-full charged one in just a few minutes.
- Power is cheap relative to petrol and diesel, especially if charging off-peak. Just how cheap? Have a read of this.
- Owners of solar panels can technically drive for free.
- Vehicle-to-grid (V2G) technology is emerging to help keep power grids stable – and earn owners some income in the process.
There’s a lot of good stuff there, and that’s by no means the full list of EV virtues. However, that’s not to say they’re without drawbacks. Here’s a summary:
- The present reliance on lithium tech for maximum battery energy density creates a resources problem, resulting in increasing material costs, that also carries its own set of environmental and social issues.
- Weight. Having to lug around heavy battery packs soaks up power and demands more from the car’s chassis, but until lighter battery chemistry is developed (like solid-state tech), BEVs need to store more energy to travel a given distance than a lighter combustion-engined equivalent would – although the efficiency of that energy is heavily in favour of electric batteries and motors.
- EVs aren’t currently a good fit for people who don’t live in city centres and need to drive long distances on a regular basis. Range anxiety is certainly a valid concern for those in regional areas.
- It’s worth noting, though, that census data shows most Australian households have more than one car – potentially making EVs a good option for those with short daily commutes and less-regular longer drives.
- Charging time is slow on household power. Not an issue for the bulk of users who charge overnight, but the convenience of simply topping up a tank of fuel in a few minutes may be missed by many.
- Don’t have a powerpoint near your car spot or need to street park? Charging is probably going to be a challenge as public stations can get crowded, there aren’t enough at each site, and reliability is patchy.
- To what extent these issues will continue into the long term, however, is unclear.
- For a while longer, price will remain a barrier for many. Retail prices for EVs are expected to creep down over the next five to 10 years as adoption rises and the price associated with making batteries (the component that adds the most cost to an electric car) falls by reducing the reliance on expensive materials as seen with lithium-iron-phosphate and sodium-ion chemistries. Combustion-engined car prices are rising, too, so the price gap is getting narrower.
Clearly, then, there are two sides to the coin for EVs and buyers need to weigh how these advantages and disadvantages will work with their own needs.
Note that we haven’t listed anything regarding emissions from the power grid, which is predominantly coal-sourced in this country – that’s independent of the vehicles themselves, and will change as renewable energy continues to steadily ramp up its share of the national energy market.
But even without that, there are plenty of drawbacks to battery-electrics that mean they’re not the zero-emissions silver bullet some people were hoping they’d be – at least not yet.
So, what do hydrogen cars do better?
- Filling up is a familiar process – pull into a refuelling station, plug in a hose and wait a few minutes. It’s virtually instant compared to charging a battery – even when using a fast-charger.
- As far as energy density is concerned, it outperforms both chemical batteries and hydrocarbon fuels. One kilogram of hydrogen contains approximately 3.4 times the energy of one kilo of petrol.
- The only emissions are water. If the hydrogen is generated entirely with green power, it can be just as eco-friendly as an electric car that’s charged from renewable sources.
2021 Toyota Mirai FCEV
- Though hydrogen cars are effectively electric cars when it comes to what delivers drive to the wheels, they don’t need a massive, heavy battery to store power. That means most of the energy stored in the tank isn’t soaked up by having to move mass.
- People who live in apartments or only have street parking won’t need to worry about charging infrastructure being provided for them – they’ll just visit a hydrogen station for a super-quick refill whenever the fuel gauge gets low.
- FCEVs typically provide more driving range than BEVs, which especially suits long-distance interstate and regional truck drivers. For example, the Hyundai Ioniq 5 BEV offers up to 507km claimed WLTP range, whereas the Nexo FCEV has up to 666km.
In many ways, hydrogen would allow drivers the most seamless transition from petrol, diesel and LPG.
The level of convenience would theoretically be the same, as filling stations would be distributed around cities in much the same way as existing fuel stations, and the refuelling time is just a couple of minutes versus the several hours needed for current electric vehicles.
Unfortunately, there are more than a few factors standing in the way of that utopian vision of a hydrogen economy.
- FCEV infrastructure is virtually non-existent (only two publicly-available in Australia) – which is significantly worse than the 400-plus BEV chargers currently available. This is hydrogen’s Achilles heel, because meaningful adoption of hydrogen cars won’t happen until there’s a sizable network of refuelling stations in place for the public to use.
- The amount of investment required to establish and maintain that network – even at existing service stations – will be staggering, because it requires special storage, needing to be contained either at massive pressure or extremely low temperatures. That makes transportation difficult, too, although CSIRO research into chemically transforming it into liquid ammonia indicates the problem of distribution could be overcome in the near future.
- Right now, commercial-scale hydrogen generation is done by reforming methane or natural gas with steam. Even cracking water into its base hydrogen and oxygen components is hardly a green process if it’s done with regular power-grid energy – not to mention the power required to compress the gas to a pressure where it contains enough energy to drive a car any meaningful distance.
- For those that think hydrogen is a more eco-friendly option than a mains-charged electric car, they may want to take a closer look at hydrogen’s supply chain first.
- Assuming a renewable energy source is used to sustain it, a hydrogen economy is simply a less efficient means of making a car move. While an electric car can be charged up directly from a solar panel or wind generator and then discharge that energy later via its motors, the hydrogen method would use that same electrical energy to convert water into hydrogen, expend more energy to compress the gas for transportation, then use more energy to distribute and pump it into a car where a fuel cell then converts the hydrogen back into electricity for the motor.
- The entire electricity-to-hydrogen-to-wheels process would lose around 62 per cent of energy once it actually drives the vehicle. That’s compared to BEVs, which are powered directly from electricity and the losses of the entire grid-to-car-to-wheels process would be around 20 per cent, instead.
- The nature of hydrogen molecules means that when compressed they can permeate even the solid walls of a storage tank, if given enough time. If your car spends long periods parked, some of the gas will still disappear without the car ever being started.
- FCEV models are even more expensive than BEVs due to a more complex powertrain process converting hydrogen with oxygen into electricity to drive the wheels. Hydrogen fuel-cells are so infant and pricey that Toyota and Hyundai are only offering leases to commercial customers who want to test it out. For example, the Camry-sized Toyota Nexo FCEV costs $63,000 on a three-year loan.
So, what’s right for Australia?
For the bulk of Australian motorists, it’s becoming increasingly apparent that pure battery-electric vehicles will be more than sufficient.
Single-charge ranges are already at the point where the average commuter would only need to pop their car on the charger once every three or four days on a public charger (or never at all by trickle charging at home instead), and with the vast majority of Aussies living in urban or suburban areas, range anxiety should rarely rear its head.
But more than that, charging infrastructure is virtually everywhere: every electric vehicle on sale today can be charged from an ordinary household power outlet. It’s fast-charging infrastructure that has yet to become widespread or properly reliable.
However, if drivers charge their cars as frequently as their phones, the need to use a fast charger becomes greatly diminished, even without the advancements in battery and charging technology that are expected in the years ahead.
Can hydrogen catch up?
The ‘chicken and egg’ issue that is only just now being overcome with BEVs is even more prevalent with FCEVs.
Not everyone lives in dense cities – and even those who do will still have the need or desire to journey into the countryside where charging infrastructure isn’t quite so accessible (and fast chargers even less so).
For them, the fast-refuelling capability and energy density of hydrogen makes more sense. Or, it would, if hydrogen fuelling stations were as plentiful as diesel and petrol bowsers – which they aren’t likely to be for many years yet.
The other technological, logistical and economic limitations of hydrogen add their own complications too.
Even in Japan, a country that’s one of the most progressive when it comes to adopting new technology, hydrogen infrastructure is still quite sparse – especially if you’re trying to travel from city to city.
And if hydrogen is a slow burn in that market, the odds of a hydrogen economy ever taking off in our country is even lower.
With hydrogen distribution still non-existent, it seems more likely that regional motorists and road-trippers will be better served by combustion-engined cars – and plug-in hybrids with a petrol or diesel engine seem like a natural compromise for that crowd.