Green hydrogen: how it works and why it’s a cleaner energy
DECARBONISATION is the most important goal across the world and requires substantial efforts in the way we generate and use our energy.
Along with using renewable technologies to produce clean electricity, another important step is decarbonising the production of a useful element like hydrogen – specifically producing ‘green hydrogen’.
Hydrogen is a chemical element and although there are almost no natural resources of pure hydrogen, it can be manufactured.
Just like electricity, hydrogen is an energy carrier that can be easily stored or transported to where it is needed.
Currently there are three different types of hydrogen production and they are differentiated by colour – grey, blue and green.
Green hydrogen is produced when renewable energy is used to derive the hydrogen from a clean source, rather than one that emits carbon.
This most commonly involves the electrolysis of water — sending an electric current through the water to separate molecules.
In order for hydrogen to be truly green hydrogen, the electricity used to break down water into the two elements must be produced from renewable sources, such as onshore wind.
Currently a hydrogen production facility is being planned at Whitelee Windfarm on the outskirts of Glasgow, the UK’S largest onshore windfarm.
This will see electricity generated by a planned solar farm and battery energy storage scheme alongside its 215 turbines used to produce green hydrogen on site, making it 100% green.
This method of obtaining hydrogen could save the 830 million tonnes of CO2 that are emitted annually when this gas is produced using fossil fuels according to the International Energy Agency.
In contrast, production of grey hydrogen, usually from natural gas, throws off carbon waste while blue hydrogen can be cleaner, it still sees the emissions of carbon produced during the production process captured and stored, or reused. Hydrogen is a zero-carbon fuel, which means it does not emit polluting gases either during combustion or during production.
It’s also easy to store, which allows it to be used subsequently for other purposes and at times other than immediately after its production.
And it can be transformed into electricity or synthetic gas and used for domestic, commercial, industrial or mobility purposes.
In the future, it is believed that low carbon hydrogen could provide cleaner energy for everything bin lorries to distilleries, film shoots to power plants, waste trucks to steel production and diggers, making it an essential technology to reach net zero emissions by 2050 and reduce the UK’S reliance on fossil fuels.