Blue hydrogen is a form of hydrogen fuel produced from natural gas, but with a cleaner twist.
In the traditional process, known as steam methane reforming (SMR) or autothermal reforming (ATR), methane reacts with high-temperature steam to produce hydrogen and carbon dioxide (CO2).
The chemical reaction is written as:
CH₄ + 2H₂O → 4H₂ + CO₂
In simple terms, natural gas reacts with steam at high temperatures to produce hydrogen and carbon dioxide.
In ordinary or “grey” hydrogen production, this CO₂ is released directly into the atmosphere, contributing to greenhouse gas emissions.
Using Carbon Capture and Storage (CCS) or Carbon Capture, Utilisation, and Storage (CCUS), up to 85–95 per cent of the CO₂ generated can be captured and stored underground in deep geological formations, such as saline aquifers or depleted oil and gas fields, or reused in industrial processes.
Hydrogen is often described in colour-coded categories based on how it is produced and the amount of carbon it emits. Grey hydrogen is made from natural gas but releases CO₂ into the air.
Blue hydrogen uses the same feedstock and method but captures and stores the CO₂. Green hydrogen, on the other hand, is produced through electrolysis of water powered by renewable energy, releasing no CO₂ at all. Blue hydrogen, therefore, sits between grey and green on the carbon spectrum, cleaner than fossil-based hydrogen but not fully carbon-neutral.
Blue hydrogen’s appeal lies in its practicality and cost efficiency.
It can be produced using existing gas infrastructure, pipelines, and refineries, making it faster and cheaper to scale than green hydrogen, which depends on large renewable energy installations and electrolysers.
It provides a transitional pathway, helping countries reduce emissions now while building up renewable capacity for the long term.
Despite its lower emissions, blue hydrogen is not emission-free.
A portion of CO₂ still escapes during capture or storage, and leaks of methane, a potent greenhouse gas, during gas extraction can offset climate benefits.
Carbon storage itself must be carefully managed to prevent leakage, and projects require public trust, rigorous monitoring, and precise regulation.
Environmental experts caution that while blue hydrogen helps reduce emissions compared to grey hydrogen, it still relies on fossil fuels and can have lasting ecological footprints.
Methane leakage during extraction and transport has a global warming potential more than 80 times that of carbon dioxide over 20 years.
Additionally, CCS facilities require substantial amounts of energy to operate, thereby increasing the overall carbon footprint.
If carbon storage sites fail or leak, trapped CO₂ could escape into the atmosphere or contaminate groundwater.
Changes in land use for pipeline networks and storage infrastructure may also disrupt ecosystems and local communities.
Blue hydrogen, however, remains an important industrial and energy feedstock. It can be used to power heavy industries such as steelmaking, cement, and chemicals, where direct electrification is difficult. It can also replace diesel in long-haul transport, trucking, and shipping, and be blended into existing natural gas pipelines to reduce carbon intensity in heating and power generation.
In electricity markets, blue hydrogen can serve as a low-carbon fuel for gas turbines and backup power systems, thereby helping to balance the intermittency of renewable energy sources, such as solar and wind.
It is also a critical input in the production of ammonia and synthetic fuels used in aviation and fertilisers, positioning it as a versatile bridge between traditional energy systems and emerging clean technologies.
Namibia’s hydrogen ambitions currently focus on green hydrogen powered by solar and wind along the coast, notably through projects like Hyphen Hydrogen Energy near Lüderitz.
Yet, blue hydrogen presents a complementary opportunity for inland use. With potential natural gas from the Kudu offshore field or the emerging Venus and Mopane discoveries, Namibia could repurpose part of its fossil fuel base into low-carbon hydrogen production.
If carbon storage sites are confirmed, for instance, in offshore depleted reservoirs or deep saline formations, blue hydrogen could bridge the gap while renewable capacity scales up.
It could also supply domestic industries such as fertiliser production, mining transport, and power generation, while green hydrogen targets export markets.
In short, blue hydrogen represents a transitional fuel for Namibia — a means to utilise its gas resources responsibly while developing the necessary infrastructure, expertise, and confidence to transition fully to a green hydrogen economy. But it will require careful environmental oversight to ensure that this “cleaner” option does not become another source of hidden emissions.
