Learn more about our technology and hydrogen…
What is Hydrogen
Hydrogen is a chemical element that represents 75% of the mass of the universe. It is also the lightest and simplest element, consisting of only one proton and one electron, however it makes up 2/3 of all molecules on our planet.
Hydrogen is a gas at room temperature, but changes to a liquid at a temperature of -252.8 ˚C, and from a liquid to a solid at -259.2 ˚C. It contains up to three times more energy per unit mass than diesel and its combustion releases neither CO2, SOx, nor fine particles—it only produces water.
1.2. Where to find it
Hydrogen can be found in stars that use it as fuel to produce energy and in “empty” spaces between the Stars. On Earth, it does not typically exist by itself in nature and must be produced from compounds that contain it, for instance, from water (H2O).
The only exception is a very small percentage that exists in the Earth’s atmosphere. This reduced percentage is due to its low density; the Earth’s gravity is not able to hold it and it floats away into outer space. The mass flow rate lost is approximately 95,000 tons of hydrogen per year.
1.3. Where is it used?
The majority of the hydrogen produced worldwide is consumed in the production of ammonia and methanol, and in the treatment of petrochemicals and steels. In addition, almost all energy sources contain carbon and hydrogen. For this reason, renewable hydrogen represents a shift away from the carbon emitting energy sources that became common during the industrial revolution.
Hydrogen is a light and extremely powerful rocket propellant. When combined with an oxidant such us liquid oxygen, liquid hydrogen yields the highest specific impulse in relation to the amount of propellant consumed of any known rocket fuel.
1.4. Interesting facts
- About 10% of the weight of living organisms is made up of hydrogen — mainly water, proteins and fats.
- Liquid hydrogen has the lowest density of any liquid.
- Hydrogen is the only element that can exist without neutrons.
- Hydrogen is believed to be one of three elements produced in the Big Bang.
- We owe most of the energy on our planet to hydrogen because the Sun’s nuclear fusion process converts hydrogen to helium releasing large amounts of energy.
Hydrogen Dual-Fuel as a transition technology
There is a need for a transition technology, to drive the use of hydrogen as major fuel for transport.
With significant capital expense involved in the infrastructure, a flexible technology that can still operate without hydrogen being available (no loss of asset) is required to generate the demand for hydrogen and hydrogen refuelling infrastructure.
Once there is hydrogen available, dual-fuel co-combustion engines can take advantage of the clean energy source. The dual-fuel co-combustion engines have shown exactly this flexibility for nearly 10 years.
The dual-fuel engines can run on 100% diesel if there is no hydrogen available, then run with hydrogen-diesel with a simple refuel process exactly like current gasoline or diesel refuelling (in some cases, even available on the same forecourt for on-road applications).
Dual-fuel co-combustion engines leverage the known long lifetime and low CAPEX and OPEX of internal combustion engines.
The changes to the internal combustion engines for dual-fuel operation are minimal (the technology can even be retro-fitted to existing engines in some cases) meaning low investment costs.
Operating, servicing, repair and maintenance are all similar to existing engines meaning low opex costs – minimal retraining. existing infrastructure for parts supply and servicing.
Hydrogen Dual-Fuel Process
How it works:-
- Hydrogen is injected into the port and aspirated in the cylinder during intake stroke.
- The gaseous hydrogen mixes further into a uniform and homogeneous mixture during the compression stroke.
- A small amount of pilot fuel (diesel) is injected into the chamber just before top dead centre.
- That diesel auto-ignites (as per a normal diesel engine, due to high temperatures and pressures in the combustion chamber) and co-combusts with all the hydrogen/air mixture, just like a gaoline/air mixture in a petrol engine.
- The exhaust gases at forced out of the cylinder during the exhaust stroke as normal, only the CO2 emissions are much lower as there was much less diesel injected to get the desired power.
Significantly lower NOx emissions are also achievable owing to the lean combustion, lower cylinder temperatures and pressures, and more homogeneous combustion process.
Hydrogen Mono-Fuel Process
How it works:-
Hydrogen mono-fuel engine.
Hydrogen is injected into the intake port and ingested with the air during the induction stroke, as per normal internal combustion engines.
A spark plug ignites the hydrogen/air mixture in exactly the same way as a normal gasoline engine.
The mixture burns pushing the piston down the bore and generating useful power at the crankshaft.
Owing to Hydrogen’s wide flamability limit, the combustion can be very lean (like a diesel engine) producing zero, or near-zero emissions (depending on mixture ratio and load).
The lean combustion (i.e. high lambda values) keep the in-cylinder temperature and pressures lower for low/zero NOx emissions.
By operating without a throttle, there are no pumping losses. This results in high thermal efficiencies, like a diesel engine.
As a zero-emissions engine, a larger engine size is required to give the same power owing to needing all that air to run that lean.
As a zero-emission power source, it is optimised for overall system cost with high combustion efficiency, delivering clean power.
Leveraging cheap internal combustion engine technology gives cost, weight and timing benefits over less mature alternative technologies.
Hydrogen Fuel Cell
How it works:-
A fuel cell is a device that converts chemical energy (energy stored in molecular bonds) into electrical energy.
A PEM (Proton Exchange Membrane) cell uses hydrogen gas (H2) and oxygen gas (O2) as fuel.
The products of the reaction in the cell are water, electricity, and heat. Since O2 is readily available in the atmosphere, we only need to supply the fuel cell with H2 which can come from an electrolysis process (see Technology page).
A fuel cell works by passing hydrogen through the anode of a fuel cell and oxygen through the cathode.
At the anode site, the hydrogen molecules are split into electrons and protons.
The protons pass through the electrolyte membrane, while the electrons are forced through a circuit, generating an electric current and excess heat. At the cathode, the protons, electrons, and oxygen combine to produce water molecules.
Fuel cells are also scalable. This means that individual fuel cells can be compiled on one another to form stacks, in turn, these stacks can be combined into larger systems.
Fuel cell systems vary greatly in size and power, from portable systems for smartphone battery recharging, to combustion engine replacements for electric vehicles, to large-scale, multi-megawatt installations providing electricity directly to the utility grid.