Frequently asked questions

Hydrogen basics

What does hydrogen actually do?

Hydrogen is an industrial raw material, and it can be combined with other things to create hydrogen-based fuels and feedstocks. There is already a market in hydrogen for various applications.

When we are talking about the potential for a hydrogen economy, we are talking about hydrogen in its pure form, where it is an energy carrier. Hydrogen stores energy which can be used at later times and can be transported to different places. In this way, hydrogen acts like a battery. However, unlike conventional batteries, hydrogen allows energy to be stored for long periods.

Hydrogen is versatile. It can be produced from a range of sources and physically converted between its gaseous and liquid states. It can displace natural gas for heating and cooking, and it can replace diesel and petrol (and other fuels) for cars, trucks, ships and planes. It can store excess electricity and feed this back into the grid when it is required. It can also be chemically converted into other forms, such as ammonia and methane. Hydrogen can be repeatedly converted across and between its physical forms and chemical forms.

When we combine these features with the possibility of hydrogen being created at scale with renewable or clean energy, we can see the great potential for hydrogen in the new energy ecosystem.

What is hydrogen used for today?

The International Energy Agency has identified around 70 million tonnes per year (MtH2/yr) of demand worldwide for “pure” hydrogen, where this is demand for hydrogen with only small levels of additives or contaminants. Hydrogen of this type is commonly used for refining oil and producing ammonia for fertilizer.

There is a further 45 MtH2/yr of hydrogen used in a mixture of gases, such as synthesis gas, for fuel or feedstock. This hydrogen is mainly used for producing methanol and steel.

Most hydrogen used today is produced from fossil fuels.

Does that mean that hydrogen is not always clean?

Yes. Hydrogen is only as clean as its inputs.

But hydrogen does not have to come from fossil fuels; the technology to produce clean hydrogen through the application of electricity to water (called electrolysis) is well established. If the electricity used for the electrolysis is from renewable sources, such as solar and wind, the resulting hydrogen has zero carbon and is clean. Hydrogen can also be produced from fossil fuels with carbon capture and storage, which means that there are low to zero carbon emissions.

How do we know if hydrogen comes from clean sources?

We expect that hydrogen producers in Australia will have to demonstrate how their hydrogen was made. This will mean showing whether the hydrogen was produced from electrolysis, fossil fuels, or other sources, and showing whether electricity and other inputs to the production were renewable. If hydrogen has been produced from fossil fuels, potential buyers will need to see if carbon emitted during the production process was captured and stored.

It will be important to get this right, particularly as so much of the value of the hydrogen economy is associated with clean energy. The countries which have expressed a desire to be major importers of hydrogen have done so to obtain clean hydrogen and Australia must ensure that it can meet its potential customers’ needs.

Why is hydrogen not already a key part of the energy mix?

Traditionally hydrogen has been more expensive than conventional fuels to produce, store and transport. There are efficiency losses from converting electricity and natural gas to hydrogen, which make the case for hydrogen more challenging. It is also energy intensive to store and deliver.

Why could it be different for hydrogen this time?

The penetration of renewable energy is at unprecedented levels, and the costs associated with renewables have fallen significantly.

Climate change has also resulted in an increased call to decarbonise the global economy, with many countries developing hydrogen strategies and plans to increase their production and/or use of clean hydrogen.

Hydrogen now has the potential to play a major part in the future energy mix.

Is hydrogen safe to use?

Yes, hydrogen is a well-established energy carrier that has been safely used in Australia for many decades.

We are already working with Standards Australia and other bodies to mirror international standards in Australia and establish the right regulatory framework to instil community confidence.

We are committed to working with our members and the community to increase public awareness of hydrogen.

Are hydrogen refuelling stations safe?

Yes, like other fuel systems, hydrogen refuelling stations must be designed and constructed in accordance with all relevant safety standards.

There are thousands of hydrogen refuelling stations already installed across Europe.

Hydrogen terminology

Why do we call hydrogen an energy carrier?

Technically hydrogen is not an energy source; hydrogen carries energy produced from other sources. The hydrogen used in industry is manufactured through chemical processes: it is split from its bond with oxygen in water or separated from carbon in natural gas and coal.

What is the difference between electricity and hydrogen as energy carriers?

Electricity is also an energy carrier. However, electricity is made up of electrons only, and hydrogen is composed of molecules and electrons. Hydrogen’s molecular structure is what allows its ability for storage for long periods and its potential to replace the current use of fossil fuels. Electricity is more limited in its uses and in its storage capabilities.

There are energy efficiency losses with conversions between hydrogen’s physical and chemical forms, and these can be significant. While hydrogen’s energy efficiency losses are less than those from processing petrol and diesel, they do make hydrogen less efficient than electricity when we look at the full processing path to its end use. This is one of the reasons why electricity and hydrogen are complementary, not competing, as energy carriers.

What is electrolysis?

Electrolysis is a process where an electric current is used to drive a chemical reaction. In the production of hydrogen, an electrolyser is used to apply electricity to water to split it into its components (hydrogen and oxygen). The hydrogen is collected and the oxygen is allowed to harmlessly escape.

Electrolysis is a well understood process and has been used in various applications for over 150 years. For hydrogen production it is a newer technology, at least for large-scale use. There are different types of electrolysers, with different costs and efficiencies, and these can be expected to improve over time.

What are the clean, green, blue, and brown hydrogen types?

'Clean' generally means there are very low to zero carbon emissions in the production of the hydrogen. This term covers hydrogen both with and without carbon capture and storage.

The colour terms denote the relative cleanness of hydrogen. Globally these terms are not consistent. In Australia:

  • Green hydrogen is carbon free: it is produced from renewable energy and non-fossil fuel sources.
  • Blue hydrogen is clean but not green: it is produced from renewable energy and natural gas but the carbon is not released into the atmosphere; it is captured and stored.
  • Brown hydrogen is not generally not clean: it is produced from fossil fuel sources (such as gas and brown coal) and the carbon is released into the atmosphere.

What is a fuel cell?

A fuel cell works like an electrolyser in reverse. It converts the energy in the hydrogen into electricity, using oxygen to trigger a chemical reaction. Water is released through the process.

Is a fuel cell vehicle an electric vehicle?

Yes, the difference is that a fuel cell vehicle generates electricity as it moves, through the chemical reaction in the fuel cell. A battery electric vehicle carries all of its electricity in a battery.

See here for how a fuel cell car works.

What is Power-to-X?

Power-to-X refers to where electricity is converted to other energy carriers or chemicals, and in the hydrogen industry this means through hydrogen produced by electrolysis.

The X refers to the result of the conversion, which can be fuel, heat, and chemicals.