Everyone seems to be talking hydrogen at the moment. But how much do you really know about it? Hydrogen is the smallest molecule in the universe and the most common chemical element. While not naturally occurring on its own on Earth, it can be produced as a gas (H2). This gas can be used as a fuel or energy source and what's more, it burns clean producing only water vapour, unlike the fuels we use today which excrete carbon dioxide.
Hydrogen is a fundamental part of water (H2O) so it can be extracted through a process called electrolysis which involves channelling an electric current through water. The energy from this current breaks the bonds in the water molecules, releasing separate hydrogen and oxygen atoms.
Watch this short video to find out more about the process.
Why do we need hydrogen fuel?
As the world moves to act on climate change, companies and countries are looking for clean alternatives to fossil fuels across the whole of society from powering our homes, to producing our food, to transporting ourselves and the things we need.
However, there are some processes that can’t be electrified, such as steel production and large scale transport. That’s where hydrogen comes in. Hydrogen made from renewable sources is a zero-emission fuel that can replace gas and oil.
Can hydrogen be exported?
Absolutely! Here in Australia, that’s exactly where we’re headed. Australia is perfectly positioned to produce an excess of wind and solar electricity, meaning that some of it could be funnelled towards creating hydrogen gas for export.
Hydrogen can be exported in carriers like ammonia or taken in dedicated ships currently being developed. According to the Australian Renewable Energy Agency (ARENA), hydrogen could become Australia’s biggest export in years to come.
Is all hydrogen green?
No. Although hydrogen burns cleanly, there are differences in the way it is manufactured. Green hydrogen is produced using renewable energy through electrolysis, as we explained above.
However, today most hydrogen gas is produced through a process called steam methane reforming. This involves separating hydrogen atoms from methane gas. This process releases carbon dioxide, the main climate pollutant. Grey hydrogen is the term used when carbon dioxide is released in steam methane reforming. Blue hydrogen is used when this carbon is captured and stored.
What else can green hydrogen be used for?
The biggest challenge currently facing the renewable energy sector is storage and stability. Hydrogen provides a great solution to this problem. By storing renewable energy as zero-carbon hydrogen gas, renewable energy becomes available around the clock without being intermittent or variable.