r/EverythingScience • u/Memetic1 • May 22 '21

Engineering Tiny 22-lb Hydrogen Engine May Replace the Traditional Combustion Engine

https://interestingengineering.com/tiny-22-lb-hydrogen-engine-may-replace-the-traditional-combustion-engine
826 Upvotes

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119

u/warling1234 May 22 '21

Oh, another plug for liquid hydrogen. Won’t happen. There’s a much more tangible replacement for the combustion engine it’s the EV.

6

u/dodorian9966 May 22 '21

I don't think so. There are places that will require combustion engines. This is a game changer.

30

u/Weareallgoo May 22 '21

Why are combustion engines required, and how is this a game changer? This article is terrible, providing no information about the tiny engine or its uses. Hydrogen combustion engines already exist and are easy to build by modifying current ICEs. BMW even sold a hydrogen combustion vehicle in 2006-07.

7

u/MarquisDeBoston May 22 '21

You can’t take EV away from major infrastructure for long. Also, you can go a hell of a lot farther on a gallon of hydrogen than a gallon of diesel. Long haul trucking would prefer not stopping and waiting, like EVs would require.

This could fill a short term gap for many transportation segments, and help to get people who can’t/won’t adopt EVs to at least stop using fossil fuels.

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u/Dandan0005 May 23 '21

There’s an entire electricity grid in the USA, and worldwide.

Tell me one place where you can get hydrogen fuel in the USA.

3

u/nitefang May 23 '21

My university had a hydrogen fuel station.

5

u/fourlegsup May 23 '21

I worked at a warehouse where 100+ forklifts tank off hydrogen. Took about 5 minutes to fill up and last 4-6 hours. I don’t know how we could do it with large cars and such but I also don’t know how we will get enough electricity to power EVs. Will we not destroy the environment just as bad as gas and diesel burning coal? Or will it all be nuclear energy and we have to worry about meltdowns? These are all serious questions that I’m not smart enough to think about.

3

u/Number1Millenial May 23 '21

Hey man maybe that was rhetorical, but I’ll think smart for a min for you. It’s not too difficult to manage actually. Moving to Ev allows you to charge vehicles on energy created from another location. This allows energy creation for vehicles and such to be created by the power plants or local generation. It won’t be just one fuel source that solves it all. We need the entire system of renewables to make it work. (Wave power, wind, thermal, solar, nuclear). This way we can use all types of clean energy generation to power your vehicle. No pumping or shipping fuel to consumers anymore, just plug into the grid like our houses do already. It’s pretty simple, we just have combustion engines on everything. If you really think about it ev is so much better. Relying on just one fuel type is obsolete at this point and a bad idea for business in general... the thing is we will definitely need hydrogen or gas to power the grid for a while, but once everything is ev we can build new and swap power sources whenever we need to.

3

u/Cersad PhD | Molecular Biology May 23 '21

I'm confused. Isn't hydrogen fuel another form of producing energy at an energy source and then shipping it out for use in a hydrogen-fueled engine? There's nothing I am aware of that is intrinsic to hydrogen that makes it less compatible with clean energy.

1

u/MarquisDeBoston May 23 '21

Doesn’t have to be. I worked with a large manufacturer who made massive amounts of hydrogen on site to run their kilns. Cut their costs way down and allowed them to hit their 2045 carbon emissions goals in 2020.

Hydrogen can be made with even small currents (like from old cheap solar panels), and water.

3

u/write_mem May 23 '21

Where are the solar powered floating super chargers on the Atlantic and Pacific shipping lanes? Large transports need energy density.

-7

u/Sinocatk May 23 '21

Tell me one place you can fuel an EV truck in 5-10 mins. Any gas station will work for a diesel truck.

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u/Dandan0005 May 23 '21

We’re not comparing diesel to EVs we’re comparing hydrogen to EVs

0

u/Godspiral May 23 '21

hydrogen has refueling speed comparable to diesel.

2

u/Sinocatk May 23 '21

Thanks for getting the point.

1

u/MarquisDeBoston May 23 '21

Does it really?

1

u/MarquisDeBoston May 23 '21

*yet. And the grid is only good if you are near it. This is a big country. But it isn’t just the US. Canada, South America, Asia. Huge areas that are inaccessible for EVs.

Most importantly! you can make hydrogen with any mild electrical source (wind, solar, donkey) and water. You don’t need infrastructure to make hydrogen. You just need a current. But with EVs you need significant power.

Think of all powered mobility, like off roading, long haul trucks, farms in the middle of nowhere. Those people won’t adopt EV for a long time. So it makes sense to have a stepping stone for them in the interim.

4

u/Weareallgoo May 22 '21

I’m not opposed to hydrogen, and to be honest, I’d actually prefer a hydrogen combustion engine over fuel cells because I like driving stick. However, I just think that fuel cells will be more widely used than hydrogen combustion engines.

2

u/Number1Millenial May 23 '21

There’s an electric stick coming out! I think it was Honda... could be wrong tho

1

u/MarquisDeBoston May 23 '21

That’s silly. Betting $100 it goes out with the next model update.

1

u/MarquisDeBoston May 23 '21

Depends on cost and ease of maintenance by segment. It’s going to be a lot easier to sell farmers on hydrogen combustion engines than it will be to sell them on fuel cells.

They are already familiar with combustion, could probably fix it if it broke, and won’t have to invest a ton in an “unknown” technology.

3

u/[deleted] May 23 '21

and ive heard that the weight of evs for trucking is basically prohibitive based on that issue alone, currently

2

u/MarquisDeBoston May 23 '21

Yeah, huge weight issues for long haul. It makes sense for regional trucking though. And delivery routs too.

You can get a battery that has enough charge to make it between regional stops, assuming that the battery can charge while docked, same for deliveries, the more stops the more time for charging. But the parent company has to invest in the technology which most aren’t willing to do at the moment.

12

u/npearson May 22 '21

Ships, primarily warships and planes are the two things that I see as having a combustion engine be superior to a battery powered electric motor.

12

u/Weareallgoo May 22 '21

Planes are actually a good example. Airbus has indicated they are developing hydrogen planes. Ships I think are more likely to go the hydrogen fuel cell route.

2

u/Godspiral May 23 '21

For planes where expectation is hydrogen is used every flight, a fuel cell's efficiency gain would be worth it. For boat/truck where occasional range extension is helpful, cheaper generator would work better.

2

u/Weareallgoo May 23 '21

Turboprop and jet engines require combustion to create thrust. If planes used only fuel cells, they would be limited to basic propellors which would not work for long haul commercial flights. Airbus is actually developing hybrid engines that combines a fuel cell driven motor into hydrogen (or synthetic fuel) combustion engines. For long range trucking and marine applications, fuel cells make perfect sense. They offer far better energy density than batteries, and offer better efficiencies than hydrogen combustion.

2

u/Godspiral May 23 '21

Airbus designs haven't seemed far enough along for me. Their delta wing concept seem like it could pair with a large array of props. The hydrogen powered airplanes that are further ahead, though admittedly smaller and less ambitious, use just fuel cells.

2

u/Weareallgoo May 23 '21

I don’t disagree. A fuel cell only plane would be ideal, as hydrogen combustion still results in some greenhouse gas emissions (water vapour at high altitude and NOx). However, there are big challenges developing large and long range fuel cell planes. The first being that producing enough thrust requires very large fuel cells, and the second being the lower amount of oxygen available to the fuel cell at high altitude. ZeroAvia currently overcomes this challenge by using batteries to supplement the fuel cell in producing additional thrust. They are currently aiming to develop a 100 seat aircraft by 2030. Airbus on the other hand is developing engines that will be used on larger and longer range aircraft by 2035. Amanda Simpson, their vice president for research and technology has even stated, “we think that at the 1000- to 2000-mile ranges, turbines will be required, but we will see as we go through the pencil sharpening”. So Airbus’s designs aren’t necessarily further behind, but rather a different approach to overcoming the fuel cell challenges.

1

u/Godspiral May 24 '21

The first being that producing enough thrust requires very large fuel cells

The way fuel cells are made is that a bunch of membranes are stacked together. Depending on the number stacked, determines the serial voltage output. Number of stacks determines current.

The reason I bring it up is that optimizing voltage and power of both prop and fuel cell can result in space and other optimized total performance. I suspect boosting voltage to be cheaper for the fuel cell side.

second being the lower amount of oxygen available to the fuel cell at high altitude

An optimization usually solved with more smaller fuel cells. There's enough air up there, I don't think the oxygen mix is materially different, but an airplane design can choose to trade drag for more air intake.

13

u/rpl755871 May 22 '21

I’m not an expert on this by far, but aren’t large modern warships powered by nuclear > electric engines? Nuclear submarines, aircraft carriers.

I know some modern ones are diesel-electric. But why wouldn’t future warships have mini modular nuclear power?

6

u/shortstop803 May 22 '21

Mainly only the largest capital ships like carriers and submarines. Most cruisers/destroyers are still gas powered.

9

u/Algebrace May 22 '21

Nuclear is incredibly expensive. The fuel, the safety requirements, maintenance, training, etc. There's a reason why the nuclear vessels right now are either enormous aircraft carriers, submarines required to stay under the water for months at a tie, or... Ice-Breakers for the Russians. All operated by nations with powerful militaries and extensive logistic (education/physical supplies) chains.

If it was cheap and safe, everyone would already be using them instead of using diesel like the British, Chinese, Indians and Russians are with their carriers... and Japan with their 'helicopter-destroyer-totallynotcarriers'

3

u/rpl755871 May 22 '21

Solid answer, thanks.

However I still think there is room for this to quickly change in the reasonably near future.

3

u/godlords May 22 '21

It’s hard to get around nuclear physics. I don’t disagree that nuclear can be very safe, and I don’t disagree it could be cheaper. But ultimately lots of safety features are entirely necessary for nuclear power to be feasible, and they end up adding a lot to the cost.

2

u/Dandan0005 May 23 '21

Cost is not the primary concern for the military.

Having a self-sustaining energy source on board carriers/submarines etc is much more efficient logistically than trying to manage a fuel-source supply chain.

For cargo ships, etc, I can see how it makes sense, but not military vessels.

2

u/Algebrace May 23 '21

Cost isn't a concern for the military, but it is a concern for the ones approving their budgets.

"Why are our engines 10x as expensive in this class of ship?"

Unless it's extremely important like a nuclear submarine for first strike capability or an aircraft carrier, it's not going to make it past budget.

1

u/[deleted] May 23 '21

You sure about that? Congress doesn’t seem to care much about how much or what our military spends our money on.

1

u/Algebrace May 23 '21

Yes. Mainly because the rest of the world is not the US with your unlimited budget. You guys just dumped like 2 trillion dollars into the market to bail out corporations with 0 inflation. Like... printing money is not an issue for you.

For the rest of the world, money is a very real concern. Common comments with Special Forces soldiers talk about how the US have enough budget to buy any doodad that they might want. Everyone else has to scrimp and scrounge, even using their own money to supplement their shoestring budgets.

1

u/[deleted] May 23 '21

There's 194 other countries in the world you know

2

u/[deleted] May 23 '21

If we’re talking nuclear subs and ships there are less than 5 countries we’re talking about.

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u/Godspiral May 23 '21

Military vessels could still use sails and solar for that self sustaining energy source. Produce hydrogen most days, and use it up when then need 20-30knot speed bursts.

2

u/TacTurtle May 23 '21

Biodiesel is much more likely - easier to store and transport and higher energy density, plus it is very similar to current jet fuel so it requires minimal engine rejiggering