Depending on production methods, hydrogen can be grey, blue or green – and sometimes even pink, yellow or turquoise – although naming conventions can vary across countries and over time.
Blue hydrogen today is expected to have a lower cost to produce than green hydrogen. The key concern many have with blue hydrogen is the reliance on fossil fuel production and the consequent environmental risks through methane emissions associated with the gas production and the less than 100% capture of the CO2.
What is green hydrogen, blue hydrogen, and so on? Producing hydrogen takes energy because hydrogen atoms don''t exist on their own — they are almost always stuck to another atom, often
Currently, most hydrogen is produced by steam reforming of methane in natural gas ("gray hydrogen"), with high carbon dioxide emissions. Increasingly, many propose using carbon capture and storage to reduce these emissions, producing so-called "blue hydrogen," frequently promoted as low emissions.
The difference between gray, blue, and green hydrogen. Hydrogen has potential as a clean fuel, depending on how it''s produced. Hydrogen fuel burns clean, so it has potential as a low-carbon energy source — depending on how it''s made. Today, most hydrogen is known as "gray"hydrogen.
Green and blue hydrogen each have a part in our clean energy playbook. Green hydrogen is the star for a zero-emission future, syncing with long-term sustainability visions. Blue hydrogen is the practical choice for now, using current gas setups and carbon capture to cut down on emissions.
The main difference between green and blue hydrogen lies in the process of obtaining the hydrogen, and in its environmental impact. Blue hydrogen does not reduce energy dependence on gas and perpetuates a development model based on fossil fuels.
What role will blue hydrogen play in decarbonizing the world''s energy systems? MIT Energy Initiative Research Scientist Emre Gençer discusses findings from research analyzing the climate impacts of blue hydrogen.
Green hydrogen stands out as an environmentally sustainable option, harnessing the power of renewable energy. Blue hydrogen, utilizing natural gas with CCS technology, provides a transitional approach to reduce carbon emissions. While economically viable, Gray hydrogen raises environmental concerns due to its direct CO
But by 2050, as the green-hydrogen industry develops, it should be more readily available, easier to produce and cost competitive with blue hydrogen by 2030, the IEA reports.