The quest for a sustainable renewable fuel source is now pointing to the most abundant element in the universe – H2 or Hydrogen.
Hydrogen is a versatile element that can be used as fuel in various applications, including transportation, power generation, and heating. In recent years, there has been a growing interest in hydrogen as a future fuel due to its clean and renewable nature.
The current interest in hydrogen as a renewable fuel source is due to the advancement of something called a fuel cell which makes hydrogen react with oxygen-generating water and resulting in a hyper-efficient, non-polluting energy system. But the source of getting the hydrogen gas is also crucial to the sustainability of this fuel. Depending on how its generated, Hydrogen is named grey, green or blue.
Black Hydrogen: Produced from coal using gasification, which is a very polluting process that produces CO2 and carbon monoxide as by-products. Some sources also calls this Brown Hydrogen. Black hydrogen is not considered a good alternative due to its negative environmental impact.
Grey Hydrogen is produced from the combustion of fossil fuels, primarily natural gas, using steam methane reforming without capturing the greenhouse gases made in the process. This is not a good option as grey hydrogen generation results in emitting pollutants and greenhouse gases to the environment. It is currently the most common and cheapest form of hydrogen production, accounting for about 95% of global hydrogen production
Blue Hydrogen refers to a better way to generate hydrogen from natural gas using steam methane reforming that uses carbon capture and storage technologies to reduce the emissions associated with grey hydrogen. This means that hydrogen generated through this method can be a cleaner alternative to grey hydrogen, although its sustainability is still subject to debate among experts. Blue hydrogen accounts for about 1% of global hydrogen production
Purple Hydrogen is when hydrogen is produced from nuclear energy. Many consider this as a better alternative to grey and blue as it has very low fossil fuel usage. Hydrogen is always a by-product of nuclear energy, and if harnessed efficiently to produce hydrogen, it could have great potential as a future fuel source. However, the use of nuclear energy also raises concerns about safety and waste management. This method is also called Red Hydrogen or Pink Hydrogen
Turquoise Hydrogen is when hydrogen is produced when a hydrocarbon fuel, such as methane, is thermally cracked into hydrogen and carbon which is also called methane pyrolysis. The by-product of turquoise hydrogen production is pure carbon, rather than CO2 produced by blue hydrogen. Turquoise hydrogen may be cheaper than electrolysis, but it still uses natural gas as a feedstock, which many consider problematic given how much methane is leaking during its production. Its research is still in the start-up phase and is being considered as a promising technology for low-carbon hydrogen production
Green Hydrogen is considered the best option for a sustainable hydrogen economy, as it uses renewable energy sources to produce hydrogen through water splitting. Although economically the first three options are more feasible at the moment, green hydrogen is becoming more cost-competitive as renewable energy technologies continue to evolve and become cheaper. Currently Green hydrogen accounts for less than 1% of global hydrogen production.
While grey and blue hydrogen may be a step towards cleaner energy, green hydrogen is the future of sustainable energy. Research is ongoing to improve the efficiency of green hydrogen generation and make it more affordable. With the efforts being put in by scientists and innovators, the future is bright for a world powered by green hydrogen. Let us all take steps towards a greener and cleaner future.