Analysis Of Down To Earth Magazine: ”How Green is Blue Hydrogen?”
Relevance
”GS 2: Government Policies & Interventions”
”GS 3: Environmental Pollution & Degradation, Growth & Development, Conservation”
Context
- Reliance Industries on February 12, 2022, announced an intent to become “the world’s top blue hydrogen producer” by repurposing a R30,000 crore synthetic gas plant to manufacture the fuel.
- Globally, there is an increased interest in blue hydrogen. Earlier this year, the EU included it under clean fuels, while the US state of New Mexico introduced a Bill to encourage its production.
- The International Energy Agency says at least 50 blue hydrogen projects are under development.
Why Hydrogen is preferred?
- Hydrogen is in focus because it is a clean source of energy and the most abundant element.
- Hydrogen is the most abundant element on the planet, but rarely in its pure form which is how we need it.
- But hydrogen does not exist on its own. It is mostly present in water in the oceans and needs to be extracted to be used as a fuel.
- On combustion it generates energy in the form of heat, releasing only water as a by-product.
- It has an energy density almost three times that of diesel.
What Decide Green, Blue, Pink etc.?
- Most commonly, hydrogen is extracted from water by electrolysis wherein current is passed through water to split hydrogen and oxygen.
- The source of power used for extraction decides how clean the hydrogen is, and prefixes such as green, blue, grey, pink indicate this.
- While green hydrogen means the fuel was extracted using renewables, blue hydrogen is extracted from natural gas.
- This is not considered to be clean since extraction of natural gas invariably results in atmospheric leakage of methane, a gas with 25 times the warming potential of carbon dioxide.
- Electric current from fossil fuel gets yellow hydrogen and from nuclear power gets pink hydrogen.
What is wrong with Blue Hydrogen?
- Blue hydrogen is hydrogen produced from natural gas with a process of steam methane reforming, where natural gas is mixed with very hot steam and a catalyst.
- A chemical reaction occurs creating hydrogen and carbon monoxide. Water is added to that mixture, turning the carbon monoxide into carbon dioxide and more hydrogen. If the carbon dioxide emissions are then captured and stored underground, the process is considered carbon-neutral, and the resulting hydrogen is called “blue hydrogen.”
- But there’s some controversy over blue hydrogen because natural gas production inevitably results in methane emissions from so-called fugitive leaks, which are leaks of methane from the drilling, extraction and transportation process.
- Methane does not last in the atmosphere as long as carbon dioxide, but it is much more potent as a greenhouse gas. Over 100 years, one ton of methane can be considered to be equivalent to 28 to 36 tons of carbon dioxide, according to the International Energy Agency.