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"Do you know that H2 is the most efficient combustible material in the world?
Let’s explain something. Diesel is dead. All the contracts, nations and big companies invest in H2 and green energy.
There has been some posts comparing hydrogen fuel cell vehicles, FCEV, to battery vehicles, BEV, and alot of focus is on efficiency of using the electricity directly, suggesting FCEV in unnecessarily complex and waste energy.
Most researchers and automotive OEMs agree that the technologies compliment each other and have different optimal use cases. For some use cases both FCEV and BEV are viable depending on how the user needs and habits.
I’m a electrical engineer working in Athens I’m involved in trying to execute hydrogen infrastructure projects here. I have spent lots of time thinking and reading about hydrogen, and try to raise knowledge and inspire people to adopt hydrogen technology
I thought I’d make a post to summarize why I think hydrogen is inevitable in the future.
This post is not focused on Nikola Motors, but their business model and their infrastructure and vehicle rollout is related.
Efficiency:
A BEV is around twice as efficient as a FCEV, no doubt about that.
BUT hydrogen produced from renewable energy offers H2 production from excess electricity, and / or electricity when there are low prices, for example in night time, or when there are lots of renewables in the total energy mix in an electric grid. Hydrogen is a great outlet for excess electricity.
Energy density per kilo:
The best mass produced batteries in world have an energy density of around 280 Wh/kilo. Hydrogen has an energy density of 33 300 Wh/kilo. That means hydrogen is 119 times more energy dense. This doesn’t matter too much when it comes to passenger cars. A tesla M3 for example carries a 480 kg battery. The corresponding weight for equal range in a FCEV passenger car is 6 kg of hydrogen. The FCEV also needs a small battery, hydrogen storage tanks and a fuel cell, so for the passenger car, there’s hardly any difference in weight.
But when it comes to larger vehicles, this starts to matter. For trucks, airplanes, trains and ships that travel long distances and carries heavy loads, the increase curve for battery weight is steep. The corresponding curve for increased weight of the hydrogen drive train is more flat.
This allows for the FCEV to transport less batteries and more goods.
Infrastructure:
In small scale, and low electromobility adaptation - BEV infrastructure is cheap and easy to build. If you live in a house, you can charge your car very cheap and convenient. A few high speed chargers are less expensive than hydrogen refuel stations.
For large scale and higher vehicle adaptation, FCEV infrastructure is cheaper and uses less land.
If we use a small city like Trelleborg as example:
Trelleborg has around 50k inhabitants and with 25k cars.
If everybody has a $1k charger at home, that’s $25M. Lets say we want to accommodate 1/10 of the cars with semi fast $3,5k chargers in the city parking lots as well there’s another $8,75M (assuming there’s no need enforcing the grid). To be able to accomodate highway travel, let’s say we build 50 fast chargers as well on the motor way in/out of the city for $0.2M each, that’s another $10M, for just the chargers, land rent or purchase not included.
A total of ~$44M for BEV infrastructure, neglecting costs for grid enforcement and land.
In Trelleborg there are now 10 fossil fuel stations for all vehicles driving in and out of the city. Assuming the same number of stations are enough for the FCEV, and each station cost $2M, the total cost is:
$20M
A full FCEV infrastructure is around half the cost of BEV infrastructure. FCEV infrastructure doesn’t need the same high costs for grid enforcement.
A system with fuel stations could also be considered more “fair” or “equal”, as not all people have access to charge at home. If you live in an apartment house or whatever.
If you can’t charge at home, and only charge at city chargers, the price per kWh is higher than if you charge at home.
Charging / refueling times:
For passenger cars, as long as you are not a taxi driver and seldom drive longer than the cars range, can charge at home, and charging / refueling times doesn’t matter too much for you, BEV will be superior due to low charging cost.
If you often drive long, or you are a commercial driver, that time matters. A FCEV refuels in about the same time as a fossil vehicle.
Time us money, and a taxi, commercial vehicle or any type of patrol car would not want to be forced to make time long stops to charge.
Temperature:
BEV loose lots of range in cold, up to 40%.
FCEV has heat and water as byproducts from the fuel cell that can be used to heat the vehicle and the drive train as a bonus without consuming extra fuel. FCEV hardly loose any range because of different temperatures. This makes FCEV fit for more variety of conditions than BEV, and a more reliable vehicle where you easier can predict your range.
Drivetrain value chain:
BEV use quite alot of mass for the batteries, with rare earth metals. China control more than 50% of the world’s known lithium resources.
Lithium for batteries need to be mined, processed, refined and after use they need to be recycled.
Fuel cells are using less material and are less complex, and easier and less energy consuming to recycle, using fewer rare earth minerals.
Hydrogen can be produced locally at, or near the fuel station with renewable electricity and water. When the hydrogen is consumed in the fuel cell, there’s only pure water and heat released.
Sector coupling:
Hydrogen allows for sector coupling, which means the same energy carrier can be used by different sectors.
Hydrogen can replace fossil fuels as a transport fuel, as a feedstock in industries, in steel-, cement-, and ammonia production. This could drive mass production of clean hydrogen, making the technology move forward and drive the cost down and availability up.
Batteries cannot do this.
This was a long text, I find H2 very interesting and hope I helped someone to learn some thing"
. Hyvä että on eriäviä mielipiteitä.
