EV BASICS 1O5: Top 5 Confrontations of Hydrogen Fuel Cell Electric Vehicle supporters | FCV Vs. BEV

Top-5-hydrogen-fuel-cell-vs-battery-electric

Hydrogen fuel cell technology has been around for so many years. It was first demonstrated by German-Swiss chemist - Christian Friedrich Schönbein in 1838 and the slogan – “Water is the coal of future” has been popular from 1874. Fuel cells have been part of the United States’ Apollo & Gemini space programs. On the passenger vehicle side, not only Japanese and Korean car makers, but BMW and Mercedes have also been experimenting FCV concepts from 1990’s.


When so many such established researchers and manufacturers experiment on this technology, it can't be wrong – Isn’t it?. However, there are also many others who disagree to fuel cell vehicles. For example, Elon Musk completely dismisses FCEV concept as stupidity, and to an extend calling fuel cell as “fool cell”😐!.

What made Elon Musk & many others to completely dismiss FCV? Why did hydrogen industry not get proper shape - even after so many years of research and existence?. This article may explore answers for some of these questions and replies to the top-5 most recurring arguments from the fuel cell vehicle supporters.



#1: Hydrogen is the most abundant element on Earth


That is completely correct. Hydrogen is the most common element in the universe, but it is not freely available on Earth; it’s available mostly in the form of water (H₂O). 

In order to use hydrogen as a fuel, water molecules first have to be broken down into hydrogen and oxygen – by passing some significant amount of electrical energy. This process is called as “Electrolysis”. 

The electrolysis process is not that efficient ; and to it’s worse, the same chemical reaction has to just get reversed inside the fuel cell vehicle later - where the energy stored in the hydrogen is converted back into electrical energy to drive the wheels. This means that only about 20-30% of the energy initially supplied can be recovered. 

Below calculation with 100 KWh electricity as an input supply, shows that a FCEV receives 23 KWh in the end as a real usable energy; whereas a BEV receives 69 KWh  – which is approximately 3 times more efficient. 

Efficiency-hydrogen-fuel-cell-vs-battery-electric



If you find the above flow/calculation difficult to understand, I hope the below picture may give a simple view on why the total value chain energy efficiency of electric vehicles are more efficient. 

Efficiency-hydrogen-fuel-cell-vs-battery-electric-1



#2: Hydrogen FCVs have longer range


This may be true a few year ago; but not anymore. A Tesla Model 3 LR – RWD gives more mileage than its peer FCEV – Toyota Mirai. I don’t need to mention other higher battery variants like Tesla Model S long range or Roadster!. 

EV type
Manufacturer, Model
Price
Range
FCEV
Toyota Mirai
$57,000
312 miles ; 512 km
BEV
Tesla Model 3 AWD LR
$49,000
322 miles ; 538 km

That said, Fuel cell vehicles have the ability to scale-up tank filling capacity much easier than adding batteries in electric vehicles. However, this advantage is questioned by the fact that there is a lack of charging infrastructure for FCVs. 

As an average EV driver, would you choose a BEV with 200 km range with enough possibilities for recharging, almost everywhere (home, work place, public infrastructure)?. Or a FCEV with 400 Km range, but with very limited refilling possibilities / stations ? 



#3: Hydrogen cars can be filled up faster 


That is completely true, FCEVs can be filled up quicker than battery electric vehicles. Continuing the same comparison of Tesla Model 3 Long Range against Toyota Mirai: Even at a best case of Tesla 250KW Supercharger V3, the Model 3 Long Range would require 22 minutes to fully charge. Whereas, Toyota Mirai might take just five minutes to fill up full - similar to conventional petrol / diesel refuelling. 

However, this comparison is totally not relevant, because the EV charging process is entirely different from refilling hydrogen. Electric vehicles can be connected to grid at almost everywhere and at most of the times, EVs are charged when they are parked at homes during night or during day at work location. So, except during long travels, the EV drivers do not face the traditional way of charging at a roadside fast charging station. 

In short: Yes, Hydrogen Fuel cell vehicles can be filled up faster; but Battery electric vehicles have less frequent need to fill-up faster. 


#4: Hydrogen fuel cell vehicles are safer 


The fact is that electric vehicles such as Tesla has the natural ability to achieve the highest safety standards – simply due to its mechanical ID concept: no engine on the front zone provides significantly larger empty space than that of conventional cars. 

The electric motors are much smaller than a combustion engine and are located directly on the axis. In addition, the large-area battery in the under-body of the vehicle ensures a low center of gravity and therefore very good road holding. No wonder why Tesla Model 3 received 5 start crash test rating. (Check the video below)



However, critics often highlight battery as an allegedly major source of danger for electric cars. If you trash all the panicked, 'assumed' news and count the ‘real’ incidents of fire on electric vehicles’ due to battery, the numbers would be rare; not even a small fraction of fire accidents in internal combustion engines.

Internal combustion engine vehicles not only carries a tank of highly flammable liquid fuel with it, but also has a complicated system of fuel lines, ignition/split electronics, an exhaust system with a catalyst and much more. All of this does not apply to an electric car. Basically, battery electric vehicle have much fewer moving parts than combustion or hydrogen fuel vehicles, thus less chances of breaking, catching fire. 

Even in the rare event of an accident, electric vehicles battery packs catch fire much slower than a fire that is fuelled by gasoline / diesel fuel. Also to note that the passenger compartment in the BEV is separated from the battery pack by a multi-layer firewall (for example, Tesla battery packs are fully isolated with an under-body titanium cladding and active cooling system), so that electric car drivers are better protected from the consequences of a vehicle fire. In addition, the future prospects for battery electric vehicles are extremely positive. As the lithium solid-state battery cells on the horizon, all the questions of battery fire can vanish. 

And what about the safety of hydrogen fuel cell vehicles ? 

In fact, there are no reliable figures available on the accidents nor the safety test passed, because there are only a few thousands of Hyundai ix35 FCEV and the Toyota Mirai have been on the streets (when comparing with 5 million+ battery electric vehicles). 

Basically, a hydrogen fuel cell vehicle is nothing more than an electric car that has a fuel cell, a hydrogen tank and the associated fuel line system instead of the large traction battery, - which means more number of moving parts that can break in comparison to a battery electric vehicle.

The Toyota Mirai has two large tanks, each with a volume of 60 litres, into which the hydrogen is pumped at a pressure of 700 bar (that is approximately about 7.2 kg of hydrogen. Don’t you think these high-pressure tank pose an at least theoretical explosion hazard?. 

No, they are not!. Luckily, I understand the basics so will not call fuel cells as hazardous. The probability of gas tank an explosion of fuel cells may be negligible, because the gas tank is always located in the best protected place in the vehicle, and is designed to withstand even large shock loads.

So, FCEVs may be better safe guarded than the internal combustion engines, but still stay inferior to the battery electric vehicles. 


#5: Hydrogen FCV are cheaper


That is not true. Hydrogen fuel cell vehicles are not cheap today; and will not be even when they achieve the ‘economy of scale’ as BEV. 

Here’s a quick comparison on initial + operational cost difference between Toyota Mirai and Tesla Model 3 – similar vehicles in terms of size, passenger and cargo capacity (though Model 3 has superior performance of 0-60 mph in 5.1 seconds, in comparison to Mirai’s 0-60 mph in 9 seconds). Anyway, let’s compare them with a real scenario in California. 

cost-difference-hydrogen-fuel-cell-vs-battery-electric
(Credits to: Paul Martin's LinkedIn post: Mirai FCEV vs Model 3 BEV )


Above table says it all; FCV is are not only expensive to buy, but also to operate simply because of their poor fuel efficiency in comparison to BEVs. The Mirai drives 5.4 times more expensive per mile , compared to Model 3.

Where Hydrogen fuel cell vehicles are still relevant?


Hydrogen fuel cells vehicle industry is clearly far behind the battery electric; and may not catch-up on the efficiency and thus total cost of ownership anytime soon. That said, the military, space and some mission critical industries are still considering FCVs, for a couple of reasons below: 

➤ First reason is obviously, the quicker fill-up time, they can be refuelled as quick as diesel/petrol vehicles. 
➤ Hydrogen can be transported to any far corners, where there is no electrical infrastructure available to recharge the batteries of BEVs. 
➤ FCVs can be refilled (at least partially) even during power outages. Compressors in the hydrogen fuel filling stations also requires electricity to run, thus during power outage the hydrogen filling stations will also suffer. However due to the pressure level difference between the storage tank (high) and vehicle tank (low), the hydrogen gas can naturally flow slowly until they reach an equilibrium. 

The bottom line is: It is clear that the hydrogen fuel cell vehicles are not best suited, right away for the mass usage in private transport as a replacement for the internal combustion engines. It may currently be a conceivable as an alternative solution for some requirement specific use cases, but we will never know how the industry will evolve! 

What are your thoughts on fuel cell vehicles developments? Do you think FCEVs will ever catch-up BEVs – as a mainstream transport for a common EV driver? or will they just stay as an use-case specific experimental technology for ever?

3 comments:

  1. As already written above: Hydrogen may work wonderfully, but is inherently less efficient than using the (solar) generated electricity directly to drive it. Check the efficiency graph of different vehicle technologies ttps://electrek.co/2016/04/26/automakers-fuel-cell-hydrogen-electric-vehicles/

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  2. Not to forget the significantly higher running costs of the fuel cell. The Toyota Mirai workshop manual suggests replacing the fuel cell every 70,000 km, and the cost is likely to be significant. On the other hand, there are already some Tesla batteries that have run noticeably over 500,000 km and still have over 90% capacity. And the batteries are getting better ...

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  3. The cost of generating and transporting Hydrogen is enormous. A single hydrogen fueling station will easily set you back a minimum of 2 million dollars. You can imagine what it will cost to operate the station. Hydrogen is also very difficult to contain without leaks. Due to its reactions with other materisls, it will require that most componets in contact with hydrogen will need to be replaced frequently.The customer at the point of fueling the car is close to a fuel under pressure of about 10000 psi. Let's hope nothing catastrophic goes wrong with the fueling.

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