[RahulNagaraj]

Toyota recently announced that they were working on developing a new hydrogen-powered engine. This new engine is said to be a 1,618cc in-line three-cylinder turbocharged unit powered by compressed hydrogen.



This new engine is said to have a faster combustion rate compared to conventional gasoline units, resulting in better responsiveness. Toyota also claims that being powered by hydrogen, the engine is environmentally friendly with zero harmful emissions. However, it does offer an exhaust note similar to that of a conventional gasoline engine.



The new hydrogen-powered combustion engine will be used on the Toyota Corolla hatchback based race car. It will participate in round 3 of the NAPAC Fuji Super TEC 24 Hours Race, to be held between May 21 - 23.

Ahead of the race, the Toyota Corolla Sport has been undergoing testing. This video gives us a chance to hear the exhaust note of the hydrogen-powered engine.

https://www.youtube.com/watch?v=2dgzKW8EKMc

Link to Team-BHP news

[vredesbyrd]

Wow. Now this is an eco-friendly engine I can live with. Only if governments and companies were pushing this hard for hydrogen engines like the do with EVs (to the point of torturing diesel owners).

Imagine, downshifting really loud and hard while not pollution and also being able to shift gears and feel the engine vibrate. We don't need EVs. We need this.

[vikram_d]

Originally Posted by vredesbyrd

Wow. Now this is an eco-friendly engine I can live with. Only if governments and companies were pushing this hard for hydrogen engines like the do with EVs (to the point of torturing diesel owners).

Imagine, downshifting really loud and hard while not pollution and also being able to shift gears and feel the engine vibrate. We don't need EVs. We need this.

I doubt it will have too many gears. Most EV's and hydrogen powered cars have a single speed gearbox built into the motor. I may be wrong about this though.

As of now transmission losses make gearboxes un-viable for these vehicles. There are number of companies out there trying to make suitable transmissions for these vehicles though.

[carthick1000]

Originally Posted by vikram_d

I doubt it will have too many gears. Most EV's and hydrogen powered cars have a single speed gearbox built into the motor. I may be wrong about this though.

As of now transmission losses make gearboxes un-viable for these vehicles.

Since the process is combustion, the torque build up cannot be done in a wider/throughout the rpm range like in an electric motor of conventional EVs. Hence it needs a transmission, just like any other ICE engined car.

Moreover transmission losses are not a lot (<10% and <5% of very efficient tranmissions). The combustion process (alongwith friction of valves, piston/rings, pumping/backpressure, vaccuum suction of air) is the most inefficient. Just to give you an idea about the overview of losses:



The process itself is less efficient than using Hydrogen in a fuel cell EV. The only advantage is zero CO2. There will still be NOx emission in certain transient conditions (acceleration, uphill etc) due to high temperature of combustion gases. But NOx aftertreatment systems should be able to handle that.

[V.Narayan]

I don't know the answers but is a piston engine really the best type of engine to combine with a hydrogen fuel? what about a gas turbine engine? Would a rotary wankel be more efficient than a traditional piston engine? In the 20th century when hydrogen as a fuel was discussed as some futuristic thing it was often suggested that hydrogen would work better with a rotary wankel than a traditional thump up-thump down piston engine. I recall an article in 1979 saying that one day when hydrogen shall be the fuel of choice the rotary wankel will dominate. A gas turbine is fundamentally more efficient than a piston engine. Only it will do as well in high ambient temperatures of the tropics.

[GTO]

Oh man, this is awesome! Thanks for sharing. I had never heard a hydrogen car exhaust and frankly, never even thought about it. But now that I think about it, the one thing I miss the most in a fast EV is the lack of an exhaust note. Hydrogen seems to provide a nicer aural experience. What's more, the only thing coming out of that exhaust is water

https://www.youtube.com/watch?v=xdSCq2G8iy0

I don't think hydrogen is going to catch on in a big way in cars though. EVs have already occupied the brain in the consumer's mind. Plus, while every big car manufacturer now has full-fledged electric car plans, it is only Toyota that is pushing the hydrogen car.

That said, I believe hydrogen tech will make a lot of sense for the big & bad boys (trucks, buses, even airplanes).

[carthick1000]

Originally Posted by V.Narayan

what about a gas turbine engine? Would a rotary wankel be more efficient than a traditional piston engine?

I think the same reasons why a gas turbine is not used (some exceptions like chrysler turbine car) in normal Petrol/diesel ICE cars might also play a role in H2 ICE cars . Some of the things I think of are (with my limited knowledge on gas turbines):

• Poor efficiency during part load/part throttle conditions of gas turbines compared to piston engines. As most passenger cars are operated in part load / steady state conditions for majority of time, the engine has to be efficient in part load. Gas turbines are more efficient only a full load
• Packaging constraints due to size and small gas turbines having more losses than a similar sized IC engine
• Emissions higher than ICE
• High velocity of exhaust gases in gas turbines, which need overengineered (overweight) exhaust systems
• No engine braking
• May be maintenance. I am not sure about this. But from reading on the aircraft related blogs on team-bhp and elsewhere, it looks like turbine engines have a fixed maintenance cycle mentioned in hundreds of hours, whereas in case of modern ICE engines it is atleast thousands of hours and probably overhaul is not needed at all during the life of the car, if maintained well.

There were few companies which experimented with hydrogen combustion engined passenger cars. Wiki link. One of which is a wankel engine (yes, the usual suspect) made by Mazda which is used in a dual fuel RX-8 (works on both gasoline and Hydrogen) in mid 2000s. There was a nice video I saw a few years ago by Jason Fenske from Engineering explained, where he explains why wankel engine might be the best way to combust hydrogen:

https://www.youtube.com/watch?v=U-n5L0cXcpg

I think in the case of Toyota, I can imagine they have factories across various continents making ICE engines for a very long time and with relatively low investment, they can upgrade these factories to churn out hydrogen combustion engines. The main reason is to cut back CO2 emissions to absolute minimum. This again not something new for automakers : Compliance Engineering as cheap as possible to market. Of course as GTO mentioned, BEVs are full throttle now and the infrastructure for hydrogen refuelling is not catching as fast as fast chargers (atleast here in Europe). So Commercial vehicles might be potential candidates than cars. But who knows what the future holds. I am staying open.

[anoop_lamba]

I thought we would be talking about an FCEV (Fuel Cell Electric Vehicle) here.
This was a pleasant surprise.

[sajaijayan]

IMHO, while Hydrogen powered on paper sounds fantastic, and, like mentioned lovely exhaust notes etc, I feel we are missing out on a few points and hence not sure this is the best way forward.
1) A whole infrastructure for Hydrogen distribution needs to be built. which would inevitably mean government control, prices controlled by government or the companies involved. With Electricity, this is already widely available and since it is already a part of our lives, they cant really control prices arbitrarily. Besides with Solar we can even generate our own electricity. Still long way to go but seems better option.
2) A hydrogen powered vehicle will be more complex, again manufacturers and dealers controlling service costs. You will need to service and maintain the vehicle at fixed intervals as with ICE vehicles. With Ev`s that really gets eliminated.

With complex technologies we basically become dependent on the manufacturer or government and they basically decide what it will cost us to maintain. No wonder the worlds largest car manufacturer does not want to let go of their income through service and maintenance and hence will definitely harp about the technology. We as consumers need to be aware and look a all aspects and decide which is better for us.

I personally am ready to give up on the beautiful exhaust sound and the feeling of gearshifts etc, for the instant exhilarating torgue of EV`s.

These are my humble opinions and hope it does not offend anyone.

[invincii]

This is such a lucrative and fun to drive idea, but I guess this won't be as cost-efficient as EVs as producing hydrogen gas, transporting it and ensuring safety at all times would be of utmost importance. EVs would be widely accepted due to their simple and maintenance-free development and operations. Just hope that battery tech gets there to improve range.

I just hope Porsche considers this since they are looking at Synthetic Fuels to keep ICE alive.

[Mafia]

In 2008-09 this was the next big thing.

I don't remember all the details, but fuel-cell and hydrogen was the next step for the ICE cars. And then NOTHING.

Electric cars have gained headway. This tech will be on the fringes as electric vehicles will be easier to manufacture and easier to maintain.

The petrolhead in me wants, the mind knows it is not happening on a commercially viable scale.

My son will be driving a whiny electric.

[carthick1000]

Jason Fenske of Engineering explains about Toyota's hydrogen combustion engine used in a prototype. Quite an insightful video touching upon the combustion process itself, CO2 and NOx emissions and the major drawbacks caused due production, consumption (efficiency) and storage in car.

https://www.youtube.com/watch?v=3IPR50-soNA

Moral of the story: Hydrogen combustion in ICE cars is impractical and inefficient.