What is Hydrogen?
Hydrogen is one of the most abundant sources of gas contributing approximately 75% of the gas in our solar system. Hydrogen is found in various things including light, water, air, plants, and animals, however, it is often combined with other elements. The most familiar combination is with oxygen to make water. Hydrogen gas is a colourless, odourless, and tasteless gas which is lighter than air. As it is far lighter than air this means it rises in our atmosphere, meaning it is not naturally found at ground level, but instead must be created. This is done by separating it from other elements and collecting the gas.
What is Green Hydrogen?
Green hydrogen is produced using electricity to power an electrolyser that separates hydrogen from the water molecule producing oxygen as a by-product. Excess electricity can be used by electrolysis to create hydrogen gas that can be stored for the future. Essentially, if the electricity used to power the electrolysers originates from renewable sources such as wind, solar or hydro, or if it originates from nuclear power – fission or fusion, then the hydrogen produced is green, in which the only carbon emissions are from those embodied in the generation infrastructure. Electrolysers are the most significant technology used for synthesising zero-carbon hydrogen fuel using renewable energy, known as green hydrogen. Green hydrogen and derivatives are an essential solution to the decarbonisation of heavy industry sectors and experts suggest will constitute up to 25% of total final energy use in a net-zero economy.
Advantages of Green Hydrogen
It is 100% sustainable as it does not emit polluting gases either through combustion or production. Hydrogen can be easily stored thereby allowing it to be used later for other purposes and/or at the time of production. Green hydrogen can be converted into electricity or synthetic gas and can be used for a variety of domestic, commercial, industrial or mobility purposes. Additionally, hydrogen can be mixed with natural gas at ratio of up to 20% without modification of the gas main infrastructure or gas appliances.
Disadvantages of Green Hydrogen
Although hydrogen is 100% sustainable it currently comes at a high cost than fossil fuels due to renewable energy being more expensive to produce. The overall production of hydrogen requires more energy than some other fuels, so unless the electricity required to produce hydrogen comes from a renewable source the entire process of production may be counterproductive. Additionally, hydrogen is a highly flammable gas, therefore extensive safety measures are essential to prevent leakage and explosions.
What is The Green Hydrogen Catapult (GHC) and what does it aim to achieve?
Members of the Green Hydrogen Catapult (GHC) are a coalition of leaders with an ambition to expand and grow Green Hydrogen Development. As of November 2021, they have announced a commitment for 45 GW of electrolysers to be developed with secured financing by 2026 with additional targeted commissioning for 2027. This is a vastly increased ambition as the initial target set by the coalition at the time of its launch in December 2020 was 25 GW. Green hydrogen has been seen as a critical element in creating a sustainable energy future as well as being one of the largest business opportunities in recent times. And has been said to be the key to allowing for the decarbonisation of sectors like steel manufacturing, shipping, and aviation.
Why Hydrogen is seen as a cleaner future?
We live in a world in which one of the collective sustainability aims is to decarbonise the fuel we use by 2050. To achieve this, decarbonising the production of a significant fuel source like hydrogen, giving rise to green hydrogen, is one of the key strategies as production of non-green hydrogen is currently responsible for more than 2 % of total global CO2 emissions. During combustion, chemical bonds are broken and constituent elements combined with oxygen. Traditionally, Methane gas has been the natural gas of choice with 85% of homes and 40% of the UK’s electricity depending on natural gas. Methane is a cleaner fuel than coal, however, when it is burnt carbon dioxide is produced as a waste product which, on entering the atmosphere, starts contributing to climate change. Hydrogen Gas when burnt only produces water vapour as a waste product, which has no global warming potential.
The UK Government have seen the use of hydrogen as a fuel and hence hydrogen homes as a way forward for a greener way of living, and have set a target for a thriving hydrogen economy by 2030. Whilst Japan, South Korea and China are on course to make considerable progress in hydrogen economy development with targets set to surpass the UK by 2030. Similarly, the European Commission has presented a hydrogen strategy in which hydrogen could support 24% of Europe’s energy by 2050.