Hydrogen engines are a type of engine that has been increasingly circulating lately. They function similarly to gasoline engines in many ways. Both use a four-stroke design for intake, compression, ignition, and exhaust.
There are considerable differences in the operation of hydrogen and fuel engines. You can browse online to find the best maintenance tips to keep your car’s engine running smoothly.
How do hydrogen engines work?
The concept of hydrogen engines is not that new since the technology for generating power from hydrogen has existed for several years.
However, what distinguishes hydrogen engines from other car engines is that the car emits steam instead of gases. There are many hydrogen engine cars, including the Chevrolet Equinox, the BMW 7 Series (745h), and the Honda FCX.
1. The difference in what your car emits
The fundamentally different vehicle produces water as a byproduct of the combustion cycle. Furthermore, due to the heat generated, NOx emissions are minimal but lower than those produced by a gasoline vehicle.
Since hydrogen is different from gas, the air-fuel ratio, compression ratio, timing, and ignition are different from those of other cars.
You might be able to use an air-fuel ratio of 180:1 and a higher compression ratio like hydrogen with a higher octane rating.
2. How do hydrogen engines power the car?
There are only two ways to power a modern car. The majority of today’s cars use an internal combustion engine that burns petroleum-based fuel, generates heat, and pushes the piston to move the vehicle forward.
However, electric cars run entirely on batteries, which supply electricity to the electric motor that propels the vehicle. Additionally, these hybrid cars are equipped with an internal combustion engine and an electric motor to switch between them while driving.
3. How does the technology work?
Fuel cells, a cross between the internal combustion engine and the battery, produce electricity using fuel from the tank. In this case, the fuel is hydrogen gas, not gasoline or diesel.
However, the fuel cell does not burn hydrogen but chemically combines it with oxygen from the air to produce water.
Then, electricity is released, which powers an electric motor to move the vehicle forward. The only waste produced is water.
Hydrogen Engine, Diesel Engine, or Natural Gas Engine
Here is a table comparing diesel engines, natural gas engines, and hydrogen engines for your reference:
| Aspect | Diesel Engine | Natural Gas Engine | Hydrogen Engine |
| Fuel Type | Diesel fuel (typically diesel oil) | Compressed Natural Gas (CNG) or LNG | Hydrogen gas |
| Combustion Process | Compression ignition | Spark ignition | Combustion with hydrogen and oxygen |
| Emissions | – Emit nitrogen oxides (NOx) and soot– May require exhaust gas aftertreatment | – Lower NOx and particulate emissions compared to diesel– Emits greenhouse gases (CO2) | – Produces only water vapor as exhaust– Considered a zero-emission vehicle |
| Fuel Consumption | Generally efficient | High thermal efficiency | High efficiency, similar to natural gas engines |
| Fuel Availability | Widely available worldwide | Access to natural gas infrastructure | Limited hydrogen refueling infrastructure |
| Fuel Cost | Moderate cost | Lower cost compared to diesel | Can be expensive due to limited supply |
| Refueling Infrastructure | Well-established | Expanding, but not as widespread as diesel | Limited availability in most regions |
| Energy Density | High energy density | Lower energy density than diesel | Low energy density |
| Engine Noise | Generally noisy | Quieter than diesel engines | Quiet operation |
| Cold Start Performance | May have issues in very cold climates | Performs well in cold conditions | Good cold start performance |
| Maintenance | Generally robust and durable | Less engine component wear | May require specialized maintenance |
| Environmental Impact | High greenhouse gas emissions | Reduced greenhouse gas emissions | Minimal environmental impact |
| Application | Common in trucks and heavy vehicles | Used in buses, fleet vehicles, and some industrial applications | Limited to niche and experimental applications |
| Future Trends | Evolving with emission reduction technologies | Growing popularity due to low emissions | Research and development for broader use |
| OEM Vehicle Availability | Widely available | Available in specific vehicle models | Limited availability, mainly experimental |
Hydrogen Engine FAQ
1. Can hydrogen engines operate in medium and heavy-duty trucks and buses?
Yes, hydrogen engines can operate in medium and heavy-duty trucks and buses, and they are being studied as an alternative to traditional diesel engines in these applications.
Hydrogen fuel cell technology is particularly promising for larger vehicles due to its high efficiency and ability to offer longer ranges compared to battery electric vehicles.
2. Are specific modifications needed to the engine to run on hydrogen?
Yes, adapting an engine to run on hydrogen typically requires modifications to accommodate hydrogen’s different combustion characteristics and properties.
These modifications can include adjusting the air-fuel mixture, ignition timing, and fuel delivery system.
3. Are there different types of hydrogen engines?
Yes, there are different types of hydrogen engines, including hydrogen internal combustion engines (HICE) and hydrogen fuel cell engines.
HICE engines burn hydrogen directly, while hydrogen fuel cell engines use hydrogen to produce electricity to power electric motors.
4. What are the challenges and limitations of hydrogen engines?
Challenges include the limited availability of hydrogen refueling infrastructure, the cost of hydrogen production and storage, and the need for special handling and safety precautions due to hydrogen gas’s flammability.
5. Is hydrogen a renewable fuel source, and how is it produced?
Hydrogen can be produced using various methods, including electrolysis (using electricity to split water into hydrogen and oxygen), steam methane reforming (extracting hydrogen from natural gas), and other renewable sources.
The environmental impact of hydrogen depends on the production method used.
Watch this video from BeyondFuel to see how a hydrogen car works!
In Summary
Thus, hydrogen engines offer drivers an environmentally friendly way to operate their vehicles without any issues.