Explaining the different hydrogen colors

Hydrogen itself is a colorless gas. But as there are different sources and processes used to make hydrogen, there are different hydrogen colors codes to identify them.

Hydrogen is the necessary link to a fully decarbonized society. It is the simplest and most abundant element in the universe and has a plethora of applications. Not only can hydrogen be stored and saved, it can be used to heat buildings, manufacture steel or go into fuel cells for trucks and ships. 

Let’s discover the different hydrogen colors

Let’s start with the basic. White hydrogen is referred to naturally occurring hydrogen. Natural hydrogen is still a little-known source of energy but some projects are already set-up and produce natural hydrogen in industrial quantities. It is the cheapest solution to produce carbon-neutral hydrogen and is competitive with fossil fuels.

Fossil fuels and hydrogen can also be a match… to produce grey hydrogen. It is produced from fossil fuels such as natural gas or coal, producing CO2 during the process. So, grey hydrogen is not climate friendly and it is the direct opposite of green hydrogen.

hydrogen colors

Green hydrogen as done by UH2, is produced through electrolysis and has zero carbon emissions. Using only clean energy and water, an electric current is used to separate water into hydrogen and oxygen. This process occurs with an electrolyser, which has the ability to create H2 from water molecules.

Blue hydrogen does not produce any CO2 emissions neither. It is produced from the steam reduction of natural gas, splitting it into hydrogen and CO2. The CO2 is later stored or processed industrially. The disadvantage is that CO2 storage is uncertain and its leakage can negatively impact the environment.

The innovation in hydrogen production has brought us more hydrogen colors in order to avoid greenhouse gas emissions. Yellow hydrogen typically refers to hydrogen made using electrolysis powered by solar energy – a more specific way to clarify precisely what form of renewable electricity is used to power the process.

More and more countries are seeking for H2 with zero carbon emissions increasing the use of Green and Yellow Hydrogen.

Other hydrogen colors codes are used to identify different types of hydrogen production: red, pink and purple hydrogen are produced using nuclear power. The use of coal as a fuel produces brown hydrogen and turquoise hydrogen is created using the thermal splitting of methane gas, which often produces emissions.

UH2 projects

Hydrogen does not exist in nature in its pure state

It has to be obtained through energy-consuming processes, to then be used in different ways, either in direct combustion, mixed into natural gas flow, or in fuel cells. The way hydrogen is produced can be completely clean or not.

UH2 works with solutions for production of green hydrogen, through electrolysis with zero carbon emissions, to then be stored and distributed, so it can be used to heat buildings, manufacture steel or go into fuel cells for trucks and ships.

Discover more about UH2 technology here.

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