Many experts today point to hydrogen as the ultimate clean energy source. However, the cleanliness of an energy source boils down to how the hydrogen is produced or extracted. While the gas itself is invisible, a widely used system of color codes helps to identify and describe how hydrogen was produced.
With this color scheme, you can instantly tell if the hydrogen production method resulted in greenhouse gas emissions and, if so, to what extent.
Regardless of how it is created, hydrogen will only yield water as a byproduct when burned. But creating hydrogen, as it turns out, can be highly carbon intensive. Fortunately, various steps can be taken to lower this impact. Some of these methods have just recently been developed in the last decade. Other methods are centuries old. Scientists mainly assign colors to hydrogen to identify how it was produced.
Production methods determine if hydrogen is classified as green, blue, turquoise, or grey. Some other interesting hydrogen production colors include pink and yellow. Black and brown hydrogen is considered the worst in terms of the carbon intensity of production.
While the naming conventions vary across regions and countries, these color codes remain standard.
As you might have guessed, the best hydrogen colors are green and turquoise. This is because green hydrogen is produced in a climate-neutral way,, and turquoise hydrogen can be produced in a carbon-negative way when the feedstock in biogas. As a result, both methods have essential roles to play in our global effort to reduce emissions to net zero in the next two decades.