By: Emma Thomas
Hydrogen can be associated with multiple colors: blue, green, and grey. This is in reference to the way hydrogen is produced. Blue hydrogen is produced from natural gas while grey hydrogen is produced from either natural gas or methane. However, green hydrogen is the only type of hydrogen that can be produced in a ‘climate neutral manner,’ making it a vital component of the path toward net zero emissions.
What is Green Hydrogen?
Green hydrogen is based on the generation of hydrogen – a universal, light, and highly reactive fuel- through electrolysis. This method uses an electrical current to separate the hydrogen from the oxygen in water. Using such a method, energy can be produced without carbon dioxide emission into the atmosphere. Furthermore, this subject was featured in several emission reduction pledges at the at UN Climate Conference, COP26 to decarbonize heavy industry, aviation and shipping.
According to the IEA (International Energy Agency), this method of obtaining green hydrogen would save approximately 830 million tons of carbon dioxide emitted annually when this gas is produced using fossil fuels.
However, the process of manufacturing green hydrogen is quite expensive, hence why it is challenging to produce and why it cannot be implemented in the short term.
As previously stated, the process of producing green hydrogen comes from electrolysis, where water molecules must be broken down into oxygen and hydrogen. The water used in electrolysis must contain salts and minerals to conduct electricity. Then two electrodes are immersed in the water and are connected to a power source and a direct current is supplied. After that, hydrogen and oxygen dissociate once the electrodes attract the ions with opposite charges to them.
Impact of Green Hydrogen
Hydrogen is slowly being incorporated as a fuel in some countries, including the USA, Russia, China, France, and Germany. Japan aspires to take this one step further and become a hydrogen economy in the future.
Green hydrogen has several useful impacts for the future, one being for electricity and drinking water generators. These elements can be obtained by reacting hydrogen and oxygen together in a fuel cell, which has proved to be especially useful on space exploration missions where the crew can be provided with water and electricity in a sustainable manner. Additionally, Green hydrogen can be stored in compressed hydrogen tanks for long periods of time. Furthermore, hydrogen’s versatility allows it to be used in consumption niches that are hard to decarbonize, such as aviation and other heavy transport.
The Green Hydrogen Catapult
The Green Hydrogen Catapult is a United Nations initiative to reduce the cost of green hydrogen and drive a massive green hydrogen scale-up by 2026. More specifically, the organization aims to scale up green hydrogen production capacity 50 times and achieve a 50% cost reduction by getting green hydrogen below two dollars per kilogram.
They have announced that it is almost doubling its goal for green electrolysers from 25 gigawatts to 45 gigawatts by 2027. The organization also believes that green hydrogen has transformational potential as an end-use energy source and an intermediate feedstock for products such as green ammonia.